Dissertations / Theses on the topic 'Fruit nutritional quality'

Thesis (MSc .(Plant Production)) -- University of Limpopo, 2016
Delayed fruit harvest (DFH) or on-tree-fruit storage is a strategy being considered to extend the harvest season of late maturing ‘Reed’ avocado. However, avocado fruit growth beyond physiological maturity is accompanied by alterations in chemical and physical properties. Thus, the study aimed to investigate the effects of delayed harvest on tree productivity, mineral nutrition and post-harvest quality of late maturing ‘Reed’ avocado and further to evaluate the fruit quality response to varying ripening temperature regimes. As treatments, fruit were harvested early, mid and late in the season, with one month apart from each harvest during 2013 and 2014 seasons. Yield and fruit size were recorded at harvest. During each harvest time, two sets of fruit samples were collected to determine the fruit nutritional content while the second set was cold stored at 5.5°C for 28 days. After storage, fruit were ripened at 16, 21 or 25°C and evaluated for post-harvest disorders, pathological diseases and fruit physico-chemical properties. Yield dropped from 42 to 12 kg/tree from early to late harvest during 2013, while treatments showed no effect during 2014. Furthermore, treatments had no effect on fruit size during both seasons. Phosphorus content decreased by 40 and 23% from early to late harvest time during 2013 and 2014 seasons, respectively. Similar decreasing patterns were observed for K, Ca and Mg content. Zinc content remained constant during 2013; however, mid-season fruit maintained higher zinc levels during 2014 season when compared to early and late harvest time. Protein content was constant for early and mid-season fruit but significantly decreased during the late harvest in both seasons. Moisture content decreased from 74.0 to 65.0% from early to late harvest during both seasons. Starch, oil and ash content were high during late harvest time in both seasons; while crude fibre was high during the mid-harvest time when compared with early and late harvest time. Internal chilling injury increased with maturity and ripening temperature. In both seasons, higher temperatures induced higher anthracnose incidences during early and mid-harvest compared with late harvest time. Similarly, vascular browning was high on fruit ripened at 16°C during early and mid-harvest time but decreased on late harvest fruit during 2013. However, low ripening temperatures induced high incidences of vascular browning during 2014 season. Stem-end rot was high on fruit ripened at 16°C than 21 and 25°C during 2014 season. xvi Physico-chemical quality parameters showed similar behaviour in both seasons. Fruit lightness increased with ripening time regardless of ripening temperature during the early harvest, but remained constant during mid and late harvest. Hue angle (h0) and Chroma (C*) values were slightly reduced during ripening. Fruit ripened at 25°C had the highest respiration rate and reached a climacteric peak earlier (day 2) than fruit ripened at 21 and 16°C (day 4). Fruit firmness and weight loss were high and rapid at 25°C followed by 21 and 16°C regardless of the harvest time. Delayed harvest had no effect on yield and fruit size. Generally, nutritional content of avocado fruit increased with fruit maturity. Furthermore, fruit maturity played a major role in the response of fruit to ripening temperature. Higher temperature enhanced fruit ripening, but was conducive for development of post-harvest diseases. Keywords: Harvesting time, nutrition, yield, fruit size, ripening temperature, post-harvest quality

Negli ultimi decenni, il consumatore è sempre più attento agli aspetti salutari della dieta, ponendo quindi particolare attenzione alla qualità generale del prodotto, dal punto di vista agronomico e commerciale fino alla qualità sensoriale e nutrizionale. Queste caratteristiche sono molto variabili tra specie differenti di fragola, ma anche all’interno di diverse cultivar appartenenti alla stessa specie. Lo scopo di questo studio triennale è stato quello di valutare e selezionare nuovi genotipi di fragola dall’elevata qualità e valore nutrizionale. I frutti di 51 genotipi di fragola derivanti da incroci interspecifici di Fragaria virginiana glauca con Fragaria x ananassa (F1), back-crossings (BC1, BC2 e BC3), varietà e selezioni di Fragaria x ananassa (Fxa) e da selezioni di Fragaria x ananassa per uso industriale (Fxa(Ind)) sono stati analizzati per parametri produttivi, sensoriali, qualitativi e nutrizionali. Nel programma di back-crossing sviluppato in questo studio, la scelta dei migliori genotipi come parentali per le varie generazioni di backcrossing (BC1, BC2 e BC3) ha permesso di ottenere nell’ultima generazione selezioni ricche di sostanze antiossidanti, ma anche con un buon recupero delle caratteristiche produttive e un miglioramento delle proprietà sensoriali rispetto alle precedenti generazioni di incrocio. A questo punto del processo di miglioramento genetico, è possibile affermare che i caratteri per l’elevata quantità di sostanze antiossidanti sono stati stabilizzati nel BC3, anche con un piccolo aumento rispetto alle popolazioni di Fragaria x ananassa e F1. La produzione in questo gruppo non è lontana dalle esigenze commerciali: con un ulteriore aumento del peso del frutto mediante reincrocio con un genitore (Fragaria x ananassa) dalle elevate performance produttive, alcuni genotipi di BC3 hanno il potenziale per diventare cultivar commerciali.
In the last few decades, the most knowledgeable consumer on the diet and its nutritional principles pays particular attention to the overall quality assessment, comprising the agronomic/commercial quality, the organoleptic quality and the nutritional quality. All those characteristics are very variable among different species, but also among different varieties within the same species. The aim of this triennial study is to select new genotypes of strawberries with high quality and nutritional value. Fruits of 51 strawberry selections from interspecific crossings of Fragaria virginiana glauca with Fragaria x ananassa (F1), back-crossings (BC1, BC2, BC3), varieties and advanced selections of Fragaria x ananassa (Fxa) and Fragaria x ananassa for industrial purpose (Ind) were analyzed for productive, sensorial, qualitative, and nutritional analyzes. In the back-crossing program developed in this study, the choice of best parental genotypes for the various backcrossing generations (BC1, BC2 and BC3) allowed to obtain in the last generation, selections rich in antioxidant substances but also with a good recovery of productive characteristics, and ameliorating sensorial properties in respect to the previous crossing generations. At this point of the breeding process, it is possible to affirm that characters for the high amount of antioxidant substances were stabilized at BC3, even with a small increase in respect to both Fragaria x ananassa and F1 populations. The production in this group is not far from commercial requirements: with further increasing of the fruit weight by backcrossing with a parent (Fragaria x ananassa) with high productive characteristics, some genotypes of BC3 have the potential to become commercial cultivars.

Title: A research of consumer attitudes to fruit snacks : A study of Thai consumers‟ attitudes toward vacuum fried crispy fruits Problem : How should Thai snack companies create their appropriate marketing planning of vacuum fried crispy fruits for satisfying Thai target consumer? Purpose: To investigate the Thai consumers‟ attitudes towards the vacuum fried crispy fruits that will be beneficial in creating the appropriate marketing planning as well as to recommend the potential marketing mix of this product to Thai snack companies Method: The research technique used in this study is mainly based on the quantitative method. By mailing the 400 surveys to the Thai respondents in Bangkok, the data will be collected and evaluated by using the statistic software program as well as using the secondary data to be a supportive source in this research. Moreover, there are marketing theories used in analyzing the data in this research in order to be more academic and reliable. Conclusion: The most influence attitude factor that motivates the Thai consumers to purchase this product is the sales promotion, in particular the samples promotion. While their attitudes to the terms of nutritional content and product quality are positive that can influence them to make a decision to purchase this product easier. Keywords: Snack fruits, Product Development, Consumer Behavior, Product Quality and Nutritional Content

Albedo breakdown known as creasing, a physiological disorder, due to abnormal separation of cells leading to the formation of irregular fractures in the white tissue (albedo) causing the creases of sweet orange rind. It causes serious economic losses to the sweet orange growers in Australia and in other orange producing areas of the world.Fruit quality, particularly albedo breakdown has been influenced by various factors such as plant water relations, genetic factors, plant nutritional status and plant growth regulators. My research investigated the development of the incidence and the severity of albedo breakdown during fruit maturation and ripening, the effects of severity of albedo breakdown on fruit quality among locations and cultivars of ‘Navel’ sweet orange. I also elucidated the influence of deficit regulated irrigation, exogenous application of surfactants added in calcium solution, exogenous application of boron and the role of ethylene in the incidence of albedo breakdown, textural properties of the rind and fruit quality of ‘Navel’ sweet oranges.The incidence and the severity of albedo breakdown increased rapidly after commercial harvest. The incidence and severity of albedo breakdown in ‘Washington Navel’ orange differed from location to location, with the lowest at Harvey as compared to three other locations. Regardless of locations and cultivars, the severity of albedo breakdown did not affect juice content, soluble solids concentration, titratable acidity, ascorbic acid, citric acid and malic acid except for decreasing succinic acid and increasing tartaric acid. Locations and cultivars significantly influenced these fruit quality parameters.The application of deficit irrigation (50% and 75% water supply of control trees) improved fruit quality in terms of increased soluble solids concentrations and acidity levels without affecting percentage of juice, pH of juice, ascorbic acid and individual organic acids in ‘Navelina’ sweet orange. The enhancement of the uptake of Ca in leaf, rind, and pulp of the fruit and the reduction in the incidence of albedo breakdown were obtained with the application of different surfactants added into aqueous solutions of 2% Ca(NO[subscript]3)[subscript]2 starting from 81 days after full bloom (DAFB) at 10-day intervals. Among four tested surfactants, ‘Tween 20’ (0.05%) was the most effective in enhancing Ca uptake, reducing albedo breakdown and improving textural properties of rind and fruit firmness while maintaining the other important fruit quality attributes in ‘Washington Navel’ sweet orange.The foliar application of boron enhanced the concentration of boron and calcium in the leaf, rind and pulp. The single spray application of boron in early summer at 600 mg.L[superscript]-1 was the most effective in increasing boron concentration in the leaf, rind and pulp of fruit, reducing the incidence of albedo breakdown and improving textural properties of rind and fruit firmness without affecting any the other fruit quality attributes in ‘Washington Navel’ sweet orange.Rind of fruit with albedo breakdown produced the higher ethylene production than the normal fruit. The exogenous application of ethylene inhibitors including AVG (200 mg.L[superscript]-1) and CoSO[subscript]4 (300 mg.L[superscript]-1) reduced the incidence of albedo breakdown and improved the rind textural properties in ‘Washington Navel’ sweet orange. Ethylene seems to be involved in the incidence of albedo breakdown.In conclusion, the severity of albedo breakdown did not affect the major attributes of fruit quality in ‘Navel’ sweet oranges. The applications of deficit irrigation, exogenous 2% Ca(NO[subscript]3)[subscript]2 containing ‘Tween 20’ as a surfactant and the exogenous spray application of boron (600 mg.L[superscript]-1) influenced the incidence and severity of albedo breakdown without affecting other fruit quality parameters. Ethylene seems to be associated with the incidence of albedo breakdown in ‘Washington Navel’ sweet orange.

Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars. Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study.

[ES] La citricultura se enfrenta a escenarios ambientales cambiantes que provocan diferentes estreses bióticos y abióticos que pueden dificultar la producción o afectar a la calidad de la fruta. El patrón sobre el cual se injerta una variedad específica es una importante herramienta para mejorar su adaptabilidad a cada área de cultivo. En la presente Tesis se realiza el estudio del efecto del patrón sobre la calidad físico-química y nutricional de la fruta en variedades de gran interés comercial en la actualidad, mandarinas 'Clemenules' y 'Tango' y naranjas sanguinas 'Tarocco Rosso' y 'Moro'. En 'Clemenules' se llevó a cabo la evaluación de la calidad de la fruta de árboles injertados sobre ocho patrones en tres momentos de cosecha durante dos campañas. Los patrones Forner-Alcaide 13 y C-35 destacaron por adelantar el cambio de color, lo que es de gran interés comercial. Por otra parte, Forner-Alcaide V17 destacó por mantener niveles óptimos de acidez hasta el final de la campaña y presentar el mayor contenido en vitamina C, flavonoides, glucosa y fructosa. Carrizo Citrange también indujo altas concentraciones de sacarosa y vitamina C. 'Tango' es una mandarina de reciente introducción en el área mediterránea de gran interés por su periodo de recolección tardío. En esta Tesis se abordó el estudio de los cambios en la calidad fisicoquímica, nutricional y sensorial de la mandarina 'Tango' injertada sobre dos patrones (Carrizo Citrange y Forner-Alcaide 5) en las dos áreas principales de producción de Andalucía. Los resultados revelaron que la calidad de la fruta se vio influenciada por la localización de las parcelas, lo que se relacionó con la composición de la textura del suelo. En ambas localizaciones, Forner-Alcaide 5 indujo mayor contenido en acidez, sólidos solubles totales, sacarosa, vitamina C y ácido cítrico en la fruta. Las determinaciones físico-químicas, junto con la evaluación sensorial permitieron establecer el momento óptimo de recolección dependiendo de las diferentes condiciones estudiadas. También se ha incluido un estudio del comportamiento postcosecha de esta variedad, ya que no existían datos en nuestras condiciones de cultivo. La mandarina 'Tango' presentó síntomas externos de daños por frío a partir de los 20 días almacenada a 1°C y 5°C. Se realizó un estudio micro-estructural para caracterizar la alteración. Los frutos del patrón Forner-Alcaide 5 presentaron una menor incidencia de los daños por frío. El almacenamiento a 9°C no comprometió la calidad externa o interna. Dentro del grupo de naranjas, en los últimos años existe una creciente demanda por las naranjas sanguinas para su consumo en fresco. Para evaluar el efecto del patrón se tomaron las variedades 'Moro' y 'Tarocco Rosso' injertadas sobre ocho patrones. La calidad interna se vio afectada por el momento de cosecha, siendo más evidente en 'Moro'. En ambas variedades el patrón afectó a los parámetros de calidad durante la maduración. En 'Moro', se observó una reducción en el color del zumo debido a la degradación de los antocianos, siendo los patrones C-35, Macrophylla y Volkameriana los que mostraron un mayor descenso. Esta degradación se relacionó con los cambio de la temperatura durante el periodo de recolección. En 'Tarocco Rosso' no se evidenció ninguna degradación, lo que sugiere que esta variedad es menos sensible a los cambios de temperatura. En esta variedad Forner-Alcaide 5 y Forner-Alcaide 13 produjeron fruta con mayor contenido en antocianos y azúcares. Además se llevó a cabo el estudio de la aptitud a la frigoconservación de las variedades de sanguinas 'Tarocco Rosso' y 'Sanguinelli'. Mientras que la calidad interna no se vio afectada por el almacenamiento (1°C, 5°C y 9°C) durante 45 días, la fruta presentó síntomas de daños por frío a 1°C. 'Sanguinelli' presentó mayor incidencia que 'Tarocco Rosso'. Estas sanguinas se pueden almacenar entre 5 y 9°C
[CA] La citricultura s'enfronta constantment a escenaris ambientals canviants que provoquen diferents estressos biòtics i abiòtics. El patró sobre el qual s'empelta una varietat específica és una important eina per a millorar la seua adaptabilitat agronòmica en cada àrea de cultiu. En la present Tesi s'ha dut a terme l'estudi de l'efecte del patró sobre la qualitat físic-química i nutricional de la fruita en varietats de gran interés comercial, mandarines 'Clemenules' i 'Tango' i, taronges sanguines 'Tarocco Rosso' i 'Moro'. En 'Clemenules' es va dur a terme l'avaluació de la qualitat de la fruita d'arbres empeltats sobre huit patrons en tres moments de collita, en dues campanyes. Entre els patrons avaluats, Forner-Alcaide 13 i C-35 van destacar per avançar el canvi de color. D'altra banda Forner-Alcaide V17 va destacar per mantindre nivells òptims d'acidesa fins al final de la campanya i va presentar el major contingut en vitamina C, flavonoides, glucosa i fructosa. Carrizo Citrange també va induir altes concentracions de sacarosa i vitamina C en la fruita. 'Tango' és una mandarina de recent introducció en l'àrea mediterrània amb gran interés pel seu període de recol·lecció que comença quan finalitza el de les clementines. En la present Tesi es van estudiar els canvis en la qualitat físic-química, nutricional i sensorial de la mandarina Tango empeltada sobre dos patrons (Carrizo Citrange i Forner-Alcaide 5) durant el període de collita en les dues àrees principals de producció d'Andalusia. La qualitat de la fruita es va veure influenciada per la localització, la qual cosa es va relacionar amb la composició de la textura del sòl. En totes dues localitzacions, Forner-Alcaide 5 va ser el patró que va induir major contingut en acidesa, sòlids solubles totals, sacarosa, vitamina C i àcid cítric en la fruita. Les determinacions físic-químiques i l'avaluació sensorial van permetre establir el moment òptim de recol·lecció depenent de les diferents condicions estudiades. També s'ha inclòs un estudi del comportament postcollita d'aquesta varietat, ja que no existien dades en les nostres condicions de cultiu. La mandarina 'Tango' va presentar símptomes externs de danys per fred a partir dels 20 dies emmagatzemada a 1°C i 5°C. Es va realitzar un estudi micro-estructural per a caracteritzar l'alteració provocada per les baixes temperatures. Els fruits del patró Forner-Alcaide 5 van presentar una menor incidència dels danys per fred. L'emmagatzematge a 9°C no va comprometre la qualitat externa o interna d'aquesta varietat. Dins del grup de taronges, en els últims anys existeix una creixent demanda per les taronges sanguines pel seu consum en fresc. Per a avaluar l'efecte del patró sobre sanguines es van prendre dues varietats, 'Moro' i 'Tarocco Rosso' empeltades sobre huit patrons. La qualitat interna es va veure influenciada pel moment de collita, la qual cosa va ser més evident en la varietat 'Moro'. En totes dues varietats el patró va afectar els canvis en els paràmetres de qualitat estudiats. En 'Moro', es va observar una reducció en el color del suc degut a la degradació del antocians. Aquesta degradació es va relacionar amb el canvi de la temperatura experimentada durant el període de recol·lecció. 'Tarocco Rosso' és menys sensible als canvis de temperatura. En aquesta varietat els patrons Forner-Alcaide 5 i Forner-Alcaide 13 van produir la fruita amb major contingut en antocianos i sucres. A mes s'aporta l'estudi de l'aptitud a la frigoconservació en les sanguines 'Tarocco Rosso' i 'Sanguinelli'. Mentre que la qualitat interna no es va veure afectada per l'emmagatzematge a cap de les temperatures assajades (1°C, 5°C i 9°C) durant 45 dies, la fruita va presentar símptomes de danys per fred a 1°C. `Sanguinelli' va presentar major incidència que 'Tarocco Rosso'. La fruita es pot emmagatzemar entre 5°C i 9°C durant 30 dies en el cas de 'Sanguinelli' i fins a 45 en e
[EN] Citriculture faces changing environmental scenarios that cause biotic and abiotic stress. The rootstock onto which a specific variety is grafted is an important tool to help to improve its agronomic adaptability to each crop area. The present Thesis was carried out to study the effect of rootstock on physico-chemical and nutritional fruit quality in some varieties of commercial interest today: 'Clemenules' and 'Tango' mandarins, and 'Tarocco Rosso' and 'Moro' blood oranges. In 'Clemenules', the fruit of the trees grafted into eight rootstocks at three harvest times was evaluated by performing studies during two seasons. Forner-Alcaide 13 and C-35 Citrange stood out for their earlier color change, which is very interesting for this variety, in which early harvesting is a relevant aspect from the commercial point of view. Forner-Alcaide V17 stood out for maintaining optimum acidity levels until the season ended and presented the highest contents in vitamin C, flavonoids, glucose and fructose. Carrizo Citrange brought about high concentrations of sucrose and vitamin C in fruit. 'Tango' is a mandarin variety that has been recently introduced into the Mediterranean Region. Its harvest time is very interesting because it starts when that of clementines ends. The present Thesis studies changes in the physico-chemical, nutritional and sensorial quality of 'Tango' fruit grafted onto two rootstocks (Carrizo Citrange and Forner-Alcaide 5) during the harvest period in the two main production areas in Andalusia. The results revealed that fruit quality during harvest was influenced by the location, which was particularly related to soil texture composition. In both areas, Forner-Alcaide 5 was the rootstock that induced higher acidity content, and more total soluble solids, sucrose, vitamin C and citric acid in fruit. The physico-chemical determinations, along with the sensorial evaluation, allowed the optimum harvest time to be established depending on the different studied conditions. This Thesis also includes a study about this variety's postharvest behavior as no data are available for our crop conditions. The 'Tango' mandarin presented outer chilling injury symptoms after being stored for 20 days at 1°C and 5°C. A microstructural study was done to characterize the alteration caused by low temperatures. The Forner-Alcaide 5 rootstock fruit showed a lower chilling injury incidence. Storage at 9°C did not compromise quality fruit. Among oranges, demand for blood oranges to be eaten fresh has grown in recent years, basically due to their high content in anthocyanins and their positive effect for human health. To assess the effect that rootstock had on blood oranges, two varieties were taken, 'Moro' and 'Tarocco Rosso', grafted onto eight rootstocks. Internal quality was strongly influenced by harvest time, which was more evident for 'Moro'. In both varieties, rootstock affected changes in the quality parameter studied. In 'Moro', juice color faded as anthocyanins degraded, and rootstocks C-35 Citrange, Macrophylla and Volkameriana showed the most marked reduction. Such anthocyanin degradation was related to the change in temperature that took place during the harvest period. In 'Tarocco Rosso', anthocyanins did not undergo degradation, which suggests that this variety is less sensitive to changes in temperature. In this variety, rootstocks Forner-Alcaide 5 and Forner-Alcaide 13 gave fruit with a higher content of anthocyanins and sugars. This Thesis also includes a study of the suitability of cold storage of two blood orange varieties: 'Tarocco Rosso' and 'Sanguinelli'. Although storage at any tested temperature (1°C, 5°C and 9°C) did not affect internal quality for 45 days, fruit displayed chilling injury symptoms at 1°C, with a higher incidence for 'Sanguinelli' than for 'Tarocco Rosso'. Fruit can be stored between 5°C and 9°C for 30 days for 'Sanguinelli' and for up to 45 days with 'Tarocco Rosso'.
This study has been supported by Instituto Valenciano de Investigaciones Agrarias and co-financed by FEDER and European Social Fund. The authors thank Anecoop S. Coop. and Frutaria Agricultura, S.L for supplying the fruit herein used and its technical support.
Morales Alfaro, J. (2021). Effect of Rootstock on the Fruit Quality of Mandarins "Clemenules" and "Tango", and Blood Oranges "Tarocco Rosso" and "Moro" [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165858
TESIS

Les effets-santé des fruits et légumes sont en partie dus à leur richesse en phytomicroconstituants comme les caroténoïdes. L'objectif de la thèse a été d’analyser au travers d’une approche interdisciplinaire, la relation « conditions de culture - séquestration des caroténoïdes – valeur santé des fruits ». La valeur santé des fruits a été évaluée à différents niveaux : I) la composition en microconstituants des fruits matures ; II) la bioaccessibilité des caroténoïdes dans un modèle de digestion in vitro ; III) le phénotypemétabolique sur un modèle d’obésité induite chez la souris mâle C57BL/6JRj supplémentée en poudre de fruit pendant 12 semaines ; IV) la fonction vasculaire de rats mâles Wistar hyperglycémiés et préalablement gavés en fruits présentant des capacités antioxydantes élevées. Pour ce faire, deux fruits décrits pour accumuler massivement des caroténoïdes ont été cultivés : la tomate (Solanum lycopersicum, six génotypes type « tomate d'industrie », H1311, M82, IL2-5, IL54, IL6-2 et IL12-4) et la baie de goji (Lycium barbarum, le cultivar FPW07). Les fruits ont été produits en environnement contrôlé sous serre sous deux régimes hydriques : un régime hydrique témoin « Control Irrigation » (CI) avec une restauration complète de l'évapotranspiration, et un régime hydrique stressé « Deficit Irrigation» (DI), pour lequel nous avons divisé par deux les volumes d’irrigation de l’anthèse jusqu’à la récolte par rapport au régime CI. Nous avons fait l’hypothèse que le déficit hydrique et/ou les traitements postrécolte (vapeur, séchage…) peuvent moduler la valeur santé des fruits en agissant sur leur composition en macro et microconstituants, les propriétés cellulaires des matrices et la bioaccessibilité des caroténoïdes. Les résultats de ces travaux montrent que dans un modèle de digestion in vitro, le DI diminue globalement la bioaccessibilité des caroténoïdes. In vivo, les résultats suggèrent que la consommation de tomate ou de baie de goji peut être associée à des effets-santé positifs dans un contexte métabolique et vasculaire avec des effets largement dépendants du génotype et du traitement postrécolte, mais peu du déficit hydrique. Ainsi, ces travaux suggèrent que le génotype et/ou le traitement post-récolte sont des leviers majeurs pour améliorer la valeur santé des fruits tout au long de la chaîne de production
The health benefits of fruit and vegetables are partly due to their richness in phytochemicals such as carotenoids. The aim of this thesis was to combine several disciplines to analyze the relationship between growing conditions, carotenoid sequestration and the health value of fruit. The health value of fruit is assessed at various levels: I) the micronutrient composition of mature fruit; II) the bioaccessibility of carotenoids in an in vitro digestion model; III) the metabolic phenotype of C57BL/6JRj mice supplemented with fruit powder for 12 weeks in a model of induced obesity; IV) the vascular function of hyperglycemic Wistar rats fed with high antioxidant capacity fruits. Two types of fruit described as carotenoid rich matrix, namely six tomato genotypes (Solanum lycopersicum, 'industrial tomato' type genotypes: H1311, M82, IL2-5, IL54, IL6-2 and IL12-4) and a lycium genotype more commonly known as 'goji' (Lycium barbarum, cultivar FPW07), were grown in a controlled environment with two water regimes. A 'Control Irrigation' (CI) regime with complete restoration of evapotranspiration, and a stressed 'Deficit Irrigation' (DI) regime, in which irrigation volumes were halved from anthesis to harvest compared with the CI treatment. We hypothesized that water deficit and/or post-harvest treatments (steaming, drying, etc.) may modulate the health value of the fruits by affecting their micronutrient composition and the bioaccessibility of carotenoids. The results of this work showed that in an in vitro digestion model, DI globally decreases carotenoid bioaccessibility. In vivo, the results suggested that tomato or goji berry consumption may be associated with positive health effects in a metabolic and vascular context, with effects largely dependent on genotype and post-harvest treatment studied, but not necessarily water treatment. Thus, this work suggests that genotype and/or post-harvest treatment are major levers to improving the health value of fruit throughout the production chain

Quality, leaf gas exchange and mineral content of fruit from internal be canopies were compared with those from extemal canopy positions in 4 citrus varieties: 'Kinnow' mandarin; 'Redblush' grapefruit; 'Valencia' orange; and 'Lisbon' lemon. Fruit weight, total juice per fruit, peel fresh and dry weight, and rind thickness of fruit from internal canopies of all 4 varieties were significantly higher compared with external fruit Mandarin, grapefruit, and orange fruit from external canopies had higher soluble solids and specific gravity. Leaves from internal canopy had higher photosynthesis than those of external canopy in all varieties. Fruit from internal canopies of all varieties had generally higher peel concentrations (%dry weight) of N, P and K due to a dilution effect, while the opposite condition existed in mandarin when these elements were expressed on a percent fresh weight basis. Peel Mg and S from external fruit were higher in all varieties, expressed as percentages of either dry weight or fresh weight. Nitrogen content of mandarin and orange juice and calcium content of grapefruit and lemon juice from external fruit were significantly higher, compared to those from internal canopy fruit. Eliminating fruit quality and mineral variations resulting from canopy positions is recommended by the means of cultural practices.

Thesis (MScAgric)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Fruit trees are exposed to various factors that can adversely affect the production of quality fruit. These factors can directly affect the fruit and the health of the tree and can be classified according to their biotic or abiotic nature, such as pathogenic attacks and drought stress respectively. One of the cultural practices used commercially to address these stresses is the application of fungicides and bactericides. The fruit production industry is under severe pressure from consumers, retailers and environmentalists, locally and internationally, to reduce chemical applications to fruit and fruit trees. The use of natural plant defence elicitor compounds and nutrients offer a potential alternative to fungicide and bactericide sprays and may also increase fruit quality and size as result of a reduction of plant stress. Trials were conducted to evaluate the efficiency of natural plant defence elicitors i.e. salicylic acid (SA) and flavonoids, in addition to mineral nutrients and bactericide/fungicides, on peach (incidence of Xanthomonas infection), plum (induced drought stress and Mg/Mn deficiencies) and apple (Mg/Mn deficiencies) fruit and trees against specified biotic or abiotic stress factors. Trial on Prunus persica cv. ‘Sandvliet’were conducted over two seasons (2008/2009 and 2011/2012) on a commercial site, Protea Farm, in the Worcester area in the Western Cape Province. During the 2008/2009 season the SA (AlexinTM, AlexiboostTM) containing treatments were applied first at 75% petal drop at concentrations of 125 and 250 ml. 100 L-1. The copper (StCu, Cu)-containing treatment was applied at 50% petal drop, while dichlorophen (XanbacTM) treatments were applied at fruit set at concentrations of 150, 300 and 200 ml. 100 L-1. The flavonoid (CroplifeTM) treatment was applied at the start of petal drop at a concentration of 150 ml.100 L-1. During the 2011/2012 season, a new flavonoid (CropbiolifeTM) treatment, as well as potassium (K-MaxTM) treatment, were incorporated into the trial and applied at concentrations of 150 and 500 ml. 100 L-1 respectively. Additionally a SA (AlexinTM) and dichlorophen (XanbacTM) treatments that performed well during the first season, were incorporated into the second season with application times and rates similar to the first season’s protocol. In addition to fruit size and quality measurements, the percentage Xanthomonas infection was determined on the leaves and fruit of the experimental trees. The SA (AlexinTM) containing treatment significantly reduced the incidence of Xanthomonas infection on leaves and fruit compared to the control in the first season. However, results varied between the two seasons, as no significant difference from the control could be obtained in the following season. The AlexinTM treatments also significantly increased the fruit size and quality. The flavonoid (CropbiolifeTM) and K (K-MaxTM) containing treatments similarly reduced the Xanthomonas infection on leaves and fruit, as well as increasing the fruit size and quality in the second season. The dichlorophen (XanbacTM) containing treatment recorded varying results as it significantly reduced the Xanthomonas infection on the fruit only in the second season. The plum trials were conducted over the 2011/2012 season on ‘Laetitia’ and ‘Songold’ plum trees, Welgevallen Experimental Farm, Stellenbosch University. Three SA (AlexinTM, AlexSal and RezistTM) containing foliar treatments were applied on the ‘Laetitia’ trees. Only two SA (AlexinTM, AlexSal) containing foliar treatments were applied on the ‘Songold’ trees. Additionally, a foliar treatment containing only K, Ca, Mg and B, was applied in both the ‘Laetitia’ and ‘Songold’ trials. All the treatments were first applied at 75% petal drop, at the same concentration of 250 ml. 100 L-1. Additionally to fruit size and quality, the mineral nutrient content of the leaves and fruit was determined. The ascorbic acid and glutathione content was determined in fruit at harvest and again after storage. None of the treatments had a positive effect on the parameters measured, except the SA (AlexinTM) containing treatments which increased the titratible acidity (TA) in both at harvest and after storage. The treatments also did not alleviate the induced stress compared to the control. The apple and plum tree trials were conducted over the 2011/2012 season in a semi-closed greenhouse, at the Welgevallen Experimental Farm, Stellenbosch. Magnesium (Mg) and Manganese (Mn) deficiencies were induced in one-year-old ‘Royal Beaut’ apple and ‘Laetitia’ plum trees planted in 10 L nursery bags, by omitting these nutrients from a standard Long Ashton soil application. Foliar treatments of Mg (MagMaxTM) and Mn (ManMaxTM) containing sprays were subsequently applied at concentrations of 250 and 75 ml. 100 L-1 respectively, after deficiency symptoms for these nutrients were visually observed. Mineral nutrient analysis of the leaves were analysed on the 13th of February for the plums and 30th of March 2012, for the apples. The Mn (ManMaxTM) containing treatment successfully overcame the Mn induced deficiency. The Mg (MagMaxTM) containing treatment did not overcome the induced Mg deficiency and was probably due to the deficient nitrogen levels in the plants, caused by an error in the initial Long Ashton nutrient solution formulation. In conclusion AlexinTM, K-MaxTM and CropbiolifeTM have shown their ability to decrease Xanthomonas infection in peaches. Additionally to their positive effect on fruit size and quality on the peaches. SA was not able to overcome the induced stress on plums, but had a positive effect on the fruit quality and size. The ManMaxTM been proven to overcome the induced Mn deficiency, while MagMaxTM was unsuccessful to overcome the Mg deficiency.
AFRIKAANSE OPSOMMING: Vrugtebome word blootgestel aan verskeie faktore wat die produksie van kwaliteit vrugte nadelig kan beïnvloed. Hierdie faktore kan ‘n direkte invloed hê op die vrugte en op die gesondheid van die boom en kan geklassifiseer word op grond van hulle biotiese of abiotiese natuur, soos patogeen infeksie en droogte stres onderskeidelik. Van die produksie praktyke wat gebruik word sluit in die toepassing van verskillende swamdoders en bakterisiede. Die vrugtebedryf is onder geweldige druk van verbruikers, die kleinhandel en omgewingsbewustes om die toediening van chemikalieë aan vrugte en vrugtebome te verminder. Die gebruik van natuurlike plant verdediging stimulerende verbindings en nutriënte, bied 'n moontlike alternatief tot die spuit van swamdoders en bakterisiede, en kan ook moontlik ʼn bydrae maak tot verbeterde vrugkwaliteit en -grootte. Proewe is uitgevoer om die effektiwiteit van die natuurlike plant verdediging stimulante, salisielsuur (SA) en flavonoïede, addisioneel tot verskillende voedingstowwe en bakterieële / swamdoders op perske, pruim en appels teen Xanthomonas infeksie, droogte stres en Mg / Mn tekorte as biotiese en abiotiese stres faktore onderskeidelik te evalueer. Die Prunus persica ‘Sandvliet’ proewe is oor twee seisoene (2008/2009 en 2011/2012) op 'n kommersiële perseel, Protea Farm, in die Worcester-area in die Wes-Kaap Provinsie, uitgevoer. Gedurende die 2008/2009 seisoen is die SA (AlexinTM, AlexiboostTM) bevattende behandelings eers toegedien by 75% blomblaarval teen konsentrasies 125 en 250 ml. 100 L-1. Die koper (StCu, Cu) bevattende behandeling is toegedien by 50% blomblaarval, terwyl die dichlorofen (XanbacTM) bevattende behandelings toegedien is by vrugset, teen konsentrasies van 150, 300 en 200 ml. 100 L-1. Die flavonoïde (CroplifeTM) behandeling is toegedien by die begin van blomblaarval teen 'n konsentrasie van 150 ml. 100 L-1. Gedurende die 2011/2012 seisoen was 'n nuwe flavonoïd (CropbiolifeTM) en ‘n kalium (K-MaxTM) behandeling toegevoeg tot die eksperiment, met ʼn toediening teen konsentrasies van onderskeidelik 150 en 500 ml. 100 L-1. Daarbenewens is die SA (AlexinTM) en dichlorofen (XanbacTM) behandeling van die 2008/2009 seisoen herhaal teen dieselfde konsentrasies en toedieningstye soos in die protokol van die eerste seisoen. Behalwe vir die bepaling van vruggrootte en –kwaliteit, is die persentasie Xanthomonas infeksie op blare en vrugte ook bepaal. Die SA (AlexinTM) bevattende behandeling het die voorkoms van Xanthomonas infeksie op die blare en vrugte betekenisvol verminder in vergelyking met die kontrole. Resultate het egter gewissel in die daaropvolgende seisoen en geen beduidende verskille tussen die behandelings is waargeneem nie. Hierdie SA-bevattende behandelings het ook tot ‘n toename in vruggrootte en -kwaliteit gelei. Die flavonoïde bevattende behandelings, (CropbiolifeTM) en K (K-MaxTM), het soortgelyke afnames in Xanthomonas infeksie op die blare en vrugte in die tweede seisoen getoon, sowel as ‘n toename in vruggrootte en -kwaliteit. Die dichlorofen (XanbacTM) bevattende behandeling het variërende resultate getoon aangesien dit slegs tot ‘n beduidende afname in Xanthomonas infeksie op die blare en vrugte in die tweede seisoen kon lei. Pruim proewe is uitgevoer in die 2011/2012 seisoen op ‘Laetitia’ en ‘Songold’ pruimbome te Welgevallen Proefplaas, Universiteit van Stellenbosch. Drie SA (AlexinTM, AlexSal en RezistTM) bevattende blaar behandelings is toegedien op die ‘Laetitia’ bome. Slegs twee SA (AlexinTM, AlexSal) blaar behandelinge is toegedien op die ‘Songold’ bome. ʼn Verdere K, Ca, Mg en B blaar behandeling is ook toegedien in beide die ‘Laetitia’ en ‘Songold’ proewe. Al die behandelings se eerste toediening het saamgeval met 75% blomblaarval, teen dieselfde konsentrasie van 250 ml. 100 L-1. Addisioneel tot vruggrootte en –kwaliteit, is die mineraal element inhoud van die blare en vrugte bepaal. Die askorbiensuur en glutatioon inhoud is bepaal in die vrugte met oes asook na opberging. Geen behandeling het 'n positiewe uitwerking op die parameters wat gemeet is getoon nie, behalwe een van die SA (AlexinTM) bevattende behandelings wat die titreerbare sure (TS) verhoog het in beide kultivars. Die behandelings kon ook nie die geïnduseerde stres verlig in vergelyking met die kontrole nie. Die appel- en pruim proewe is uitgevoer gedurende die 2011/2012 seisoen in 'n semi-geslote glashuis te Welgevallen Proefplaas, Universiteit van Stellenbosch. Magnesium (Mg) en Mangaan (Mn) tekorte is geïnduseer in een-jaar-oue ‘Royal Beaut’ appel en ‘Laetitia’ pruim bome, aangeplant in 10L kwekerysakke, deur dié elemente uit ʼn toediening van standaard Long-Ashton voedingsoplossing aan die grond weg te laat. Mg (MagMaxTM) en Mn (ManMaxTM) bevattende blaarspuite is daarna toegepas teen onderskeidelik konsentrasies van 250 en 75 ml. 100 L-1. ʼn Minerale analise van die blare is uitgevoer op 13 Februarie, op die pruime en 30 Maart 2012, op die appels. Die Mn (ManMaxTM) bevattend behandeling het die Mn-geïnduseerde tekort verlig. Die Mg (MagMaxTM) bevattende behandeling het nie die geïnduseerde Mg-tekort verlig nie. Dit is moontlik toe te skryf aan die stikstof tekort in die plante wat te wyte was aan ʼn foutiewe Long Ashton voedingsoplossing formulasie wat aanvanklik toegedien is. Ten slotte het AlexinTM, K-MaxTM en CropbiolifeTM getoon dat hul die vermoë het om Xanthomonas infeksie te verminder, asook om vruggrootte en kwaliteit in perskes te verbeter. SA was nie in staat om die geïnduseerde stres op pruime te oorkom nie, maar het 'n positiewe uitwerking op die vruggroote en kwaliteit gehad. ManMaxTM het getoon dat dit ʼn geïnduseerde, visuele Mn tekort kan oorkom, terwyl MagMaxTM onsuksesvol was om die Mg-tekort te oorkom

Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO4 (3000 mg∙L-1, 4000 mg∙L-1, or 5000 mg∙L-1), MgSO4 (1%, 2%, or 3%), KNO3 (1%, 2%, or 3%), or deionized (DI) water (control). Fruit were analyzed for fruit split incidence, yield, fruit number per tree, fruit diameter, fruit mass, mass of all arils in fruit, mass of 100 arils, total soluble solids (TSS), titratable acidity (TA), antioxidant activity (AA), total phenolics (TP), and mineral nutrient concentrations of leaves and fruit. Foliar applications of MgSO4 and ZnSO4 resulted in significantly lower fruit split incidence. Treatments had no significant effect on fruit number per tree, fruit diameter, and mass, mass of all arils in fruit, or mass of 100 arils. Leaf N, K, S, Mn, and Zn were significantly affected by the treatments. TSS and TA were not affected significantly by treatments. AA ranged from 77.8-84.3 percent inhibition of 2,2’-diphenyl-1-picrylhydrazyl and TP ranged from 2489-3046 mg·L-1 gallic acid equivalents, with some KNO3 treatments significantly affecting these parameters. Fruit mineral nutrient concentrations were characterized and Zn-treated trees had greater fruit Zn concentrations. The results suggest that foliar ZnSO4 or MgSO4 could be used to decrease fruit split incidence and increase nutritional content of ‘Wonderful’ pomegranate and any of the three tested foliar nutrients could be applied as a foliar fertilizer without negatively impacting fruit yield, size, internal quality, bioactivity, or mineral nutrient concentration.

Au cours des procédés d’appertisation, qui impliquent des traitements thermiques généralement pratiqués à hautes températures, la qualité nutritionnelle des produits alimentaires est souvent altérée. En effet, certaines vitamines, telles que la vitamine C, sont très thermolabiles.L’objectif du projet PREDINUT était de proposer un outil d’aide à la décision afin de prévoir la quantité de vitamine C (marqueur de qualité nutritionnelle) détruite dans des conditions données de durée/température, afin de pouvoir optimiser les procédés.Un thermorésistomètre Mastia®, a été utilisé pour établir des conditions de température et pression représentatives des procédés d‘appertisation. L’impact de la variation de paramètres physico-chimiques tels que le pH, la concentration initiale en acide ascorbique ou encore la pression partielle en oxygène dans l’espace de tête, sur la dégradation de l’acide ascorbique a été étudié en solution modèle. Des études ont également été menées dans des produits alimentaires (purée de pomme, purée de carotte et jus de carotte) afin d’établir un profil de destruction de la vitamine C dans des aliments concrets. Dans ce projet, la plage de température étudiée est de 95 à 125 °C, le pH fixé en solution modèle est de 2,5 à 5,5 en conditions d’anaérobiose stricte, et de 3,5 en conditions d’aérobiose (3,5 étant la valeur de pH de la majorité des fruits), les concentrations initiales en acide ascorbique varient de 15 à 90 mg/100mL, et la pression partielle en oxygène de 30000 à 100000 Pa. Dans les produits alimentaires, les expériences ont été réalisées par enrichissement en acide ascorbique à hauteur de 450 mg/L, la valeur du pH ne subissant pas d’ajustement.Des modèles ont été établis pour décrire le profil cinétique de la dégradation de la vitamine C en aérobiose et en anaérobiose. En l’absence d’oxygène la dégradation de la vitamine C suit une cinétique d’ordre 1 (sauf à pH = 4,5). En présence d’oxygène (conditions aérobies) la vitesse de dégradation croit avec la pression partielle d’oxygène, mais très peu avec la température. Des ordres apparents variant de 0,5 à 0,75 en fonction de la pression partielle en oxygène dans l’espace de tête, s’avèrent mieux ajuster les données que l’ordre 1.Dans les aliments, le mécanisme de dégradation de la vitamine C apparaît beaucoup plus complexe, et la vitesse de réaction n’évolue pas de façon continue avec le temps, avec des phases de plateau suivies de réaccélérations. Une connaissance fine des mécanismes et des espèces chimiques impliquées sera nécessaire pour comprendre cette évolution
Canning involves thermal treatments performed at high temperatures, which may alter nutrional quality of food products. Indeed, some vitamins, like vitamin C, are very heat sensitive.The aim of the project PREDINUT was to propose a decision support tool that predicts vitamin C (as indicator of nutritional quality) degradation in given conditions of time/temperature, in order to optimise processes.A thermoresistometer Mastia® was used to reach the temperature and pressure conditions encountered during canning. The impact of the variation pH, initial concentration of ascorbic acid or again partial pressure of oxygen in headspace, on ascorbic acid degradation was studied in model solution. Studies were also performed in apple puree, carrot puree and carrot juice in order to obtain a destruction profile of vitamin C in real foods. . The temperature range studied was from 95 to 125 °C, the fixed pH in model solution was from 2.5 to 5.5 in strict anaerobic conditions, and 3.5 in aerobic conditions (3.5 being the pH value of common fruits), initial concentrations of ascorbic acid varied from 150 to 900 mg/100mL, and the partial pressure of oxygen from 30000 to 100000 Pa. Foods were enriched in ascorbic acid (up to 450 mg/mL), and the pH value was not adjusted.Models were established to describe the kinetics of vitamin C degradation in aerobiosis and anaerobiosis. En absence of oxygen ascorbic acid degradation was well described by a first order kinetics (except at pH = 4.5). In presence of oxygen the degradation speed increased with head-space oxygen’s partial pressure but very little with temperature. Apparent reaction orders varying from 0.5 to 0.75, depending on the partial pressure of oxygen in the headspace, fitted the data better than first-order.In foods, degradation kinetics of vitamin C appeared more complex, with eventual presence of plateaus followed by acceleration of the reaction. Definitely more knowledge on mechanisms is needed to predict ascorbic acid degradation in real foods

La production de dattes ne cesse d’augmenter d’une saison à une autre ce qui engendre des pertes essentiellement lors des étapes de manutention et de commercialisation. De plus, l’étape de manutention post-récolte joue un rôle important dans le maintien de la qualité des dattes. Dans ce cadre et afin de préserver les qualités organoleptique et nutritionnelle des dattes après récolte tout en améliorant leur valeur commerciale, des essais de conservation et de traitement post-récolte ont été mis en place. L’effet de la conservation des dattes en fonction de la température, du temps, de l’utilisation d’atmosphère modifiée lors du stockage et d’un traitement thermique sur la fermeté, la couleur, et les teneurs en sucres, acides organiques, polyphénols et parois cellulaires a été étudié. Les dattes du cultivar ‘Deglet Nour’ récoltées en 2017 et 2018 au stade Tamr ainsi que les dattes communes ‘Arichti’, ‘Bouhattam’, ‘Bser Hlou’ consommées à un stade de maturité précoce (stade Khalal) ont été conservées à -18, 0, 2 et 4 °C pendant 3, 6 et 9 mois et à 2 °C pendant 30 et 60 jours, respectivement. La spectroscopie Moyen Infrarouge (MIR) en tant que méthode non destructive et non ciblée a permis de mettre en évidence l’effet de l’année de récolte par rapport à la composition chimique et de discriminer les échantillons de dattes ‘Deglet Nour’ conservés à 4 et 2 °C. Le rendement en parois cellulaires assimilées aux fibres, ainsi que les procyanidines représentant 98% des polyphénols totaux sont stables durant la conservation du cultivar ‘Deglet Nour’ et du cultivar ‘Arichti’ quel que soit la température et la durée de conservation. En revanche, ces composants sont ceux qui sont les plus affectés par les conditions de conservations dans le cas des cultivars ‘Bouhattam’ et ‘Bser Hlou’. Ce dernier est le cultivar le plus ferme et le plus apprécié par les consommateurs, en raison notamment de l’augmentation des teneurs en sucres réducteurs affectant son goût sucré lors de la conservation. De ce fait, une conservation des dattes ‘Deglet Nour’ à -18 °C pourrait être une solution pour un stockage à long terme, par contre en raison des coûts énergétiques élevés, 2 °C est la température optimale de conservation. En outre, afin de bien valoriser les dattes communes et prolonger leur durée de vie, la durée de conservation peut être prolongée pour le cultivar ‘Arichti’, une optimisation de la température de conservation pour le cultivar ‘Bser Hlou’ et ‘Bouhattam’ sera cependant nécessaire. Les dattes précédemment citées ont été également conservées dans différents types d’emballages à atmosphère modifiée (EAM) à 2 °C pendant 3, 6 et 9 mois pour le cultivar ‘Deglet Nour’ et pendant 30 et 60 jours pour les cultivars ‘Arichti’, ‘Bouhattam’ and ‘Bser Hlou’. D’une façon générale, ces résultats ont montré que les EAM ont le même impact que la température et la durée de conservation sur la qualité des dattes. Par conséquent, leur utilisation dans les industries de conditionnement de dattes va entrainer des coûts supplémentaires sans effets bénéfiques. L’impact d’un traitement d’hydratation sur les qualités organoleptique et nutritionnelle des dattes a également été évalué. Le traitement des dattes ‘Deglet Nour’ de trois usines de conditionnement différentes, à une vapeur d’eau saturée à 60-62 °C pendant 4 heures a montré qu’elles deviennent plus souples comme attendu, tandis que les paramètres nutritionnels sont resté stables. La spectroscopie Moyen Infrarouge (MIR) a permis de discriminer les dattes des trois usines et il est suggéré qu’elle soit adoptée par les stations de conditionnement comme une nouvelle technique prédictive et non destructive. Ce résultat confirme que le traitement d’hydratation pourrait être fortement recommandé pour valoriser les dattes sèches de faible valeur commerciale, cependant il doit être optimisé pour les dattes très sèches
The production of dates is increasing every season, causing losses especially during post-harvest handling andmarketing. Post-harvest handling plays an important role in maintaining date palm. In order to preserve organolepticand nutritional quality of date palm fruits after harvest with improving their commercial value, storage experiments andpost-harvest treatments have been assayed.The effect of different storage conditions of temperature, time and modified atmosphere, as well as the effectof heat treatment of dates, on firmness, colour, sugars, organic acids, polyphenols and cell walls and compositions havebeen studied.‘Deglet Nour’ date palm fruits of two harvest seasons (2017 and 2018) as well as common date cultivars‘Arichti’, ‘Bouhattam’ and ‘Bser Hlou’ consumed at early maturity stage (Khalal stage), were stored at -18, 0, 2 and 4°C for 3, 6 and 9 months and at 2 °C for 30 and 60 days, respectively. Mid Infrared Spectroscopy (MIR) as a nontargetedmethod allowed to highlight a year effect on 'Deglet Nour’ chemical composition and to discriminate samplesstored at 4 and 2 °C regarding to major components (moisture, sugar, organic acids...). Cell wall yields (assimilated tofiber) as well as procyanidins, accounting for 98% of total polyphenols, were stable during ‘Deglet Nour’ and ‘Arichti’cultivars storage regardless of temperature and time conditions. However, these same components were the mostaffected by storage conditions for ‘Bouhattam’ and ‘Bser Hlou’ cultivar. This latter, was the softest cultivar and themost appreciated by consumers, may be because of reducing sugars increase affecting its sweet taste. Thus, stored fruitsat -18 °C could be the solution for a long-term storage but due to its high energetic costs, 2 °C must be the optimaltemperature. Moreover, in order to valorize common dates palm and prolong their shelf life, storage time could beprolonged for ‘Arichti’ cultivar with temperature storage ptimization for ‘Bser Hlou’ and ‘Bouhattam’ cultivars.Date palm fruits mentioned above, were also stored under Modified Atmosphere packaging (MAP) at 2°Cduring 3, 6 and 9 months for ‘Deglet Nour’ and during 30 and 60 days for commons cultivars (‘Arichti’, ‘Bouhattam’and ‘Bser Hlou’). In general, differences were observed on physical and chemical parameters using different MAPstreatments for ‘Deglet Nour’date palm fruits. Dates became darke with MAPT and MAPA storage. Dates palm storedunder this latter MAP bag showed an increase on procyanidins, some cell walls compositions, fructose and citric acid.Firmness loss of this cultivar was delayed with MAPZ storage with polyphenols stability. This latter bag type conservedfirmness and colour of the three studied cultivars (‘Arichti’, ‘Bouhattam’ and ‘Bser Hlou’) were stabe with no differencecomparing to control (without MAP). Organic acids, cell walls yield and composition, polyphenols were also stableduring storage. Only sugars contents of every cultivars had different behaviour.These results showed that MAP bags had very lower benefical effects than storage time and temperature on ‘date palmquality. So, their use in date processing industries could have more costs with no apparent effects.The organoleptic and nutritional quality of ‘Deglet Nour’ date palm was also evaluated before and afterhydration treatment commonly used in date prcessing units (DPU), in order to become more commercially valued andto minimize waste generated along the date palm fruit supply chain. Hydration treatment under saturated steam at 60-62°C for 4 hours impoved date fruits texture as expected while nutritional parameters were quite stable. Mid InfraredSpectroscopy (MIR) allowed to discriminate samples from the three DPUs suggesting to be adopted in DPU as a newpredictive and no destructive technique. So, hydration treatment could be highly recommended to valorize fruit byproducts.However, it needs to be optimized for the very hard-type dates
انتاج التمور في ارتفاع مستمر من موسم الى اخر مما يجعل مراكزالفرز و التخزين تتخلص من كميات هائلة من التمور المتضررة أثناءعمليات الفرز والتسويق. هذه العمليات تلعب دورا هاما في الحفاظ على جودة التمور. ومن أجل الحفاظ على الجودة الغذائية للتمور بعد الجنيمع تحسين قيمتها التسويقية، تم القيلم بتجارب التخزين وبعض معالجات ما بعد الجني.وقد تم دراسة تأثير ظروف التخزين المختلفة من درجة الحرارة، مدة الخزن وتقنية الجو الهوائي المعدل، وكذلك تأثير معالجة التمور الجافةعلى الصلابة، اللون، السكريات، الأحماض العضوية، البوليفينول وجدران الخلايا النباتية (الالياف) ومكوناتها.تم تخزين تمور ’ دقلة النور’ لصابة 2017 و 2018 والأصناف الأخرى من التمور الأقل انتشارا مثل ’ الارشتي’، ’ بو حتم’، ’ بسر حلو’18 درجة مائوية وفي 2 درجة مائوية لمدة - ,0 ,2 , التي تستهلك في مرحلة متقدمة من النضج (خلال)، لمدة ثلاثة، ستة وتسعة أشهر في 430 و 60 على التوالي. اثبت التحليل الطيفي بالأشعة تحت الحمراء الوسطى ان سنة الجني لها تاثير على العناصر الكيميلئية للتمور’ دقلةالنور’ وقامت بتمييز التمور المخزنة في 2 و 4 درجة مائوية بالنسبة لاهم مكوناتها (الماء، السكريات، الأحماض العضوية...). اثبت النتائجان جدران الخلايا النباتية (الالياف) وان أكبر مكونات البوليفينول (بروسيانيدين) كانت مستقرة اثناء تخزين تمور’ دقلة النور’ و ’ الارشتي’،بغض النظر عن درجة حرارة ومدة التخزين. نفس هذه العناصر كانت الأكثر تاثرا بعوامل التخزين بالنسبة لاصناف’ بو حتم’ و ’ بسرحلو’. هذا الصنف الأخير كان الأكثر ليونة مع تغير بنية جدران الخلايا على الرغم من انه أكثر صنف قابلية لدى المستهلك، من الممكنبسبب ارتفاع كمية السكريلت السريعة التي اثرت على مذاقه الحلو.فبحيث ان تخزين التمور ’ دقلة النور’ في - 18 درجة مائوية من الممكن ان يكون أحسن حل على مدى طويل، لكن نظرا لتكاليفة الطاقيةالباهضة، تخزين التمور في 2 درجة مائوية يجب ان يكون أفضل حل. بصفة عامة لم يكن هناك خسائر هامة للقيمة الغذائية بالنسبة لاصنافالتمور الاخرى اثناء التخزين، مما يجعل التمديد في مدة التخزين ممكنا بالنسبة اصنف’ الارشتي’ مع البحث عن درجة حرارة تخزين ناجعةالصنف ’ بسر حلو’ و’ بو حتم’.تم ايضا تخزين انواع التمور المذكورة اعلاه بتقنية الجو الهوائي المعدل في 2 درجة مائوية لمدة ثلاثة، ستة وتسعة أشهربالنسبة ’ لدقلةالنور’ ولمدة 30 و 60 يوم بالنسبة للاصناف الأخرى. بصفة عامة هناك اختلافات في العناصر الفيزيلئية والكيميلئية ’ لدقلة النور' المخزنةفي كل أنواع تقنيات الجو الهوائي. ' دقلة النور' المخزنة في أكياس ترندلايف و ايباك. أصبحت داكنة الون.دقلة النور المخزنة في أكياس ' سجلت ارتفاعا في مكونات جدران الخلايل, بروسيانيدين, الفروكتوز و حامض السيتريك. تخزين' دقلة النور'في أكياس زويباك اخرت في ليونتها مع استقرار في البوليفينول. هذه النتائج اثبتت ان تخزين التمور في اكياس الجو الهوائي المعدل لم تكنذو نجاعة عالية مقارنة بعوامل الحرارة والمدة الزمنية.لون وصلابة التمور من اصناف ’ الارشتي’، ’ بو حتم’، ’ بسر حلو’ اثبتت استقرارها بعد تخزينها في أكياس زويباك, لكن بعدم ايجاد فرقمقارنة بالتمور المخزنة بدون اكياس الجو الهوائي المعدل, مثلها مثل بقية العناصر الفيزيلئية والكيميلئي بصفة عامة. هذا يثبت ان استعمالهافي مصانع تخزين التمور ليس له جدوى اقتصادية واضحة.تم دراسة مدى تاثر القيمة الغذائية لتمور ’ دقلة النور’ الجافة على إثر معالجتها وترطيبها بالطريقة الهعتدة في اغلب مصانع تخزين التمور62 درجة مائوية لمدة 4 ساعات - لتكون ذات قيمة تسويقية عالية ولتقليص كمية الخسائر. تقنية ترطيب التمور على طريقة البخار في 60اثبتت نتائج ناجعة كما كان متوقع مع المحافضة على استقرار المكونات الغذائية. طريقة معالجة التمور بترطيبها هي طريقة متصوح بهالكنها غير ناجة للتمور الأكثر جفافا التي تحتاج تطوير في هذه التقنية

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The diferences in climatic conditions and the appropriate nutritional management are crucial for productivity and fruit quality. Southern Brazil is the main apple production region, with the States of Rio Grande do Sul (RS) and Santa Catarina (SC) the major producers. The aim of this research was to evaluate the quality of apple fruits grown in Southern Brazil,considering the nutritional variables and weather conditions during the 2012-2013 season. The study was carried out in the regions of Vacaria-RS, Bom Jesus-RS, Caxias do Sul-RS, Fraiburgo-SC and São Joaquim-SC. Seventy-six orchards were selected. The concentrations of nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and calcium (Ca) were quantified in samples of leaves and fruits. The N/Ca and (K+Mg)/Ca ratios were also quantified in the fruit samples. Sulfur (S), cooper (Cu), zinc (Zn), iron (Fe), manganese (Mn) and boron (B) were quantified in leaf samples. At harvest, 20 fruits were ecaluate for flesh fiirmness (N), soluble solids (SS;%), titratable acidity (TA; % malic acid), iodine-starch, and transverse and longitudinal (mm) diameter. After refrigerated storage under air atmosphere (AA) for 120 days (0±1 °C/ RH of 90±5 %) followed by seven days at 20 °C, fruit were analyzes for flesh firmness, SS and AT. Climatic data of rainfall (mm), number of days of precipitation,temperatures (maximum, minimum and average) (°C) and Wind speed (m/s) were evaluated in the diferente regions. The averageconcentrations (mg kg¯¹ of fresh matter) in the fruit of de N, P, K,,Ca and Mg were, respectively, 295, 83, 1.399, 47 e 36 mg kg¯¹ in Fuji , the mean values of (K+Mg)/Ca andN/Ca relatios were 30 and 6,4 for Gala , and 35 and 6,7, for Fuji , respectively. Gala and Fuji apple fruits had P concentration below the lower minimum critical value (˃100 mg kg¯¹) and the N/Ca ratio was below the upper critical value (˂14 mg kg¯¹). Fuji apple fruit had Ca concntration below the lower critical value (˃40 mg kg¯¹), and the (K+Mg)/Ca ratio above the uppercritical value (˂30 mg kg¯¹). In Gala apples, colder regions favor the occurrence of lower N concentration, higher Ca concentration and lower N/Ca and (K+Mg)/Ca ratios in the fruit. The average concentration (g kg¯¹ of dry matter) in the leaves of N. P. K. Ca, and Mg were, respectively, 21, 2, 17, 10, 3 g kg¯¹ in Gala , and 23, 2, 16, 12, 3 g kg¯¹ in fuji . Apples harvested in diferente regions showed great variation in terms of starch-iodine index, and thus, the postharvest results were signicantly affected by fruit maturity at harvest. During the experimental period, there were substantial diferences of climatic conditions between regions. Fraiburgo had the lowest average anual rainfall (1,170 mm) and Bom Jesus the highest one (1,749 mm). The Monthly average temperatures were highest in Caxias do Sul and lowest in São Joaquim
As diferenças nas variáveis climáticas e o manejo nutricional adequado são fatores determinantes para produtividade e qualidade dos frutos. A região Sul do Brasil destaca-se no cultivo de macieiras, sendo os Estados do Rio Grande do Sul (RS) e Santa Catarina (SC) os principais produtores. Este trabalho teve por objetivo determinar a qualidade de frutos de macieira produzidas no Sul do Brasil, avaliando as variáveis nutricionais e as condições meteorológicas durante a safra 2012-2013. O estudo foi realizado nas regiões de Vacaria-RS, Bom Jesus-RS. Caxias do Sul-RS, Fraiburgo-SC e São Joaquim-SC. Selecionou-se 76 pomares. As concentrações de nitrogênio (N), fósforo (P), potássio (K), magnésio (Mg) e cálcio (Ca) foram determinadas em amostrar de folhas e frutos. Determinou-se também as relações N/Ca e (K+Mg)/Ca nas amostras de frutos. Enxofre (S), cobre (Cu), zinco (Zn), ferro (Fe), manganês (Mn) e boro (B) foram determinados nas amostras de folhas. Na colheita, 20 frutos foram avaliados quanto à firmeza da polpa (N), sólidos solúveis (SS; %), acidez titulável (AT; % ácido málico), índice de iodo-amido e diâmetro transversal e longitudinal (mm). Após a armazenagem refrigerada sob atmosfera do ar (AA) durante 120 dias (0±1°C/UR de 90±5%), seguido de mais sete dias a 20°C, foram realizadas análises de firmeza de polpa, SS e AT dos frutos. Dados climáticos de precipitação pluvoométrica (mm), número de dias de chuva, temperaturas máxima, mínima e média (°C) e velocidade do vento (m/s) foram avaliados nas diferentes regiões. As concentrações médias (mg kg¯¹ matéria fresca) de N, P, K, Ca e Mg nos frutos foram , respectivamente, 295, 83,1.299, 47 e 36 mg kg¯¹, para Gala , e 260, 73, 1.331, 39 e 28 mg kg¯¹, para Fuji . Os valores médios das relações (K+Mg)/Ca e N/Ca foram 30 e 6,4 para Gala , e 35 e 6,7 para Fuji , respectivamente Maçãs Gala e Fuji apresentaram concetração de P abaixo do nível crítico inferior (˃ 100 mg kg¯¹), e a relação N/Ca ficou abaixo do nível crítico superior (˂14 mg kg¯¹). Maçãs Fuji apresentaram valores de Ca abaixo do nível crítico inferior (˃40 mg kg¯¹), e a relação (K+Mg)/Ca acima do nível crítico superior (˂30 mg kg¯¹) em maçãs Gala , regiões mais frias favorecem a ocorrência de menores teores de N, maiores teores de Ca e menores relações N/Ca e (K+Mg)/Ca. As concentrações médias nas folhas (g Kg¯¹ matéria seca) de N, P, K, Ca, Mg foram, respectivamente, 21, 2, 17, 10, 3 g kg¯¹, para Gala , e 23, 2, 16, 12, 3 g kg¯¹, para Fuji . S maçãs colhidas nas diferentes regiçoes apresentaram grande variação no índice de iodo-amido, e assim, os resultados de pós-colheita foram afetados significativamente pelo ponto de colheita. Durante o período avaliado, houve diferença nas variáveis climáticas entre regiões. Fraiburgo apresentou os menores volumes médios de precipitação pluvial anual (1.170mm) e Bom Jesus os maiores valores (1.749 mm). As temperaturas médias mensais mais altas foram observadas em Caxias do Sul, e as menores em São Joaquim

A positive relationship between foliar copper levels and fruit firmness in apricots was established in the late 1980’s. A review of the literature and discussions with both national and international researchers led to research upon the influence of foliar applied copper on fruit quality. Studies were initiated using cherries, which in addition to being a soft fruit also suffer from rain induced fruit cracking. Results of initial studies suggested that the treatment should be applied to other fruit crops to determine if similar responses occur in these. To this end two further experiments were conducted on apples. As a result of this research, a practical means of reducing rain induced damage to cherries was developed. This finding has major ramifications for all cherry growing regions of the world.
Doctor of Philosophy (PhD)

A positive relationship between foliar copper levels and fruit firmness in apricots was established in the late 1980’s. A review of the literature and discussions with both national and international researchers led to research upon the influence of foliar applied copper on fruit quality. Studies were initiated using cherries, which in addition to being a soft fruit also suffer from rain induced fruit cracking. Results of initial studies suggested that the treatment should be applied to other fruit crops to determine if similar responses occur in these. To this end two further experiments were conducted on apples. As a result of this research, a practical means of reducing rain induced damage to cherries was developed. This finding has major ramifications for all cherry growing regions of the world.

The aim of this thesis was to investigate how preharvest calcium (Ca) and nitrogen (N) nutrition, and low crop load during fruit development affect fruit quality and postharvest disease of Keitt mangoes (Mangifera indica L). Calcium, N and crop load were chosen because previous research and Gower reports implicate them as major factors in internal disorders, poor colour development, and postharvest disease in mangoes grown in the Mareeba district of Queensland. The symptoms and incidence of the internal fruit disorders seen in Keitt mangoes growing in Queensland were investigated to determine their similarity to other forms of internal disorders, and to develop a severity rating scale to assess fruit in later experiments. While the observed disorder in Keitt shared some symptoms with other named forms of disorders, not all symptoms were similar. The typical symptoms of patches of watery translucent flesh that breakdown and discharge cellular fluids in the more severe cases, are referred to as watery-pulp breakdown throughout this thesis. Watery-pulp breakdown-affected fruit had lower mesocarp Ca concentrations (0.05% dw) than healthy fruit (0.10% dw), but not N, K, P, and Mg concentrations. The severity of symptoms increased as maturity of the fruit increased, and early harvest may be a useful strategy to minimise the disorder. The first nutrition experiment investigated the effects of Ca, N and crop load on fruit quality in 6-year-old Keitt trees, between 1997 and 2000. Trees were fertilised with high (>1 kg Ca tree-1 and >300 g N tree-1) or nil concentrations of Ca and N, and natural or 70%-reduced crop loads. Fruit were assessed for watery-pulp breakdown, fruit colour, postharvest disease, fruit firmness, yield and average fruit weight. Although Ca was applied above the normal industry rates, there were no significant increases in fruit-Ca or leaf- Ca concentrations, or response in any of the fruit quality parameters measured. The factors influencing Ca concentrations in mesocarp were shown to be changes in dry matter accumulation and periodic reductions in Ca supply. Fruit from the high N treatment had significantly (p < 0.05) greater incidence and severity of postharvest side disease lesions (mainly anthracnose) but not stem lesions (mainly stem-end rot). The high N treatments also significantly (p < 0.05) reduced the percentage of yellow skin, and the percentage and intensity of red blush colour in ripe fruit. Watery-pulp breakdown, fruit firmness and average fruit weight were not significantly affected by the high N treatments. Reducing the crop load throughout fruit development significantly (p<0.05) increased the average fruit weights and the incidence of watery-pulp breakdown, but did not significantly affect the other fruit quality parameters measured. Further studies on Ca uptake and distribution were carried out in 3 additional experiments. The effects of Ca supply on fruit quality were investigated in a similar manner to the first experiment, by varying soil-applied Ca. Increased rates (1726 g tree-1 Ca) and more frequent applications (fortnightly) of gypsum were used to overcome leaching. Although soil Ca concentrations at harvest (0 - 30 cm deep) were increased by the Ca treatment, no significant effects were observed on fruit quality. The effect of leaf transpiration on leaf and fruit Ca concentrations was investigated by reducing leaf transpiration with an anti-transpirant throughout flowering and fruit development. Reduced leaf transpiration did not significantly affect mesocarp or leaf Ca, N, P, Mg, K, B concentrations, indicating the balance of transpiration mass flow between leaves and fruit is not a major factor in mango fruit Ca accumulation. Temporal changes in uptake and distribution of Ca during flowering and fruit development were studied using elemental strontium (Sr) as a Ca analogue. Sr and Ca concentrations were not similar during the experiment making prediction of Ca uptake and distribution based on Sr uptake and partitioning unsuitable. The effect of high N in increasing postharvest fruit disease in the first experiment was further studied to confirm the earlier results and to identify the mechanisms involved in this relationship. Fruit with a range of N concentrations were produced from trees fertilised with a range of N rates (0 417 g tree-1). The incidence and severity of postharvest anthracnose (C. gloeosporioides) increased as fruit-N increased, with significant relationships between anthracnose severity and exocarp-N concentration (anthracnose severity in sprung fruit = 163.18x2 151.85x + 36.987, r2 = 0.97**). High N had a similar effect on the incidence of Penicillium sp., Rhizopus sp., Guibnardia sp., or Epicoccum sp., but not Dothiorella sp. (stem-end rot). The antifungal compounds 5-n-pentadecyl resorcinol and 5-n-heptadecenyl resorcinol were influenced by exocarp-N in two ways. Resorcinol concentrations were lower in fruit with high exocarp-N than low-N fruit, and concentrations decreased faster in ripening fruit with high exocarp-N. The differences in resorcinol concentrations between high- and low-N fruit was strongest in the sprung stage of ripeness, and positive exponential relationships were found between exocarp-N and concentrations of 5-n-pentadecyl resorcinol (p=0.006. r2= 0.92) and 5-n-heptadecenyl resorcinol (p=0.016, r2=0.82). There were also positive relationships between anthracnose severity and 5-n-pentadecyl resorcinol (p=0.003, r2=0.86) and 5-n-heptadecenyl resorcinol (p=0.003, r2 =0.87). No significant differences were observed in exocarp morphology to explain the N effect on postharvest disease incidence or severity. The effect of timing of application of N on fruit quality and disease was investigated in a field experiment on 8-year-old Keitt mango trees on which N was applied at flowering, at mid fruit development, 2 weeks pre-harvest, or not applied (control). N applied at flowering and mid fruit development, significantly increased the severity of postharvest Colletotrichum sp. (p<0.05) Penicillium sp., Rhizopus sp., Guibnardia sp., and Epicoccum sp. (p<0.01) in ripe fruit. N applied 2 weeks prior to harvest did not significantly affect postharvest diseases, with fruit having similar anthracnose severity and incidence to the nil-N (control) treatment. Fruit Ca concentrations were not able to be manipulated by imposing field treatments. The inability to easily manipulate fruit Ca concentrations indicates it is unlikely to be an effective tool to manipulate fruit quality in mango. Nitrogen was shown to greatly influence fruit quality, having a major influence on postharvest disease, skin colour and sunburn susceptibility, but not watery-pulp breakdown. Increased N was also shown to reduce concentrations of natural antifungal resorcinol compounds as fruit ripened, making fruit more susceptible to postharvest rots. The sensitivity of fruit quality to N makes management of N a critical tool in managing fruit quality and disease susceptibility. Reduced crop load had a major effect on the incidence and severity of watery-pulp breakdown, indicating tree management practices to maximise crop load will also reduce the severity of watery-pulp breakdown.

In South Africa, a shortage of litchi cultivars to expand the very short harvesting period has seriously threatened the viability of the local export orientated Litchi Industry. Only two cultivars have dominated commercial plantings for more than a century, namely ‘HLH Mauritius’ and ‘McLean’s Red’. The marketing period of litchis from South Africa coincides with large export volumes from competitor countries such as Madagascar, resulting in lower returns for local growers. To address this situation, the late season cultivar ‘Wai Chee’ was imported amongst others from Australia. ‘Wai Chee’ is harvested at a time in South Africa when there is a gap in worldwide litchi production, making the cultivar potentially very profitable. However, its potential and subsequent use in the industry is affected by small fruit size and questionable internal quality. As the South African Litchi Industry is export orientated and the qualities of ‘HLH Mauritius’ fruit currently dictate export requirements, solutions need to be found to improve fruit size and fruit quality in ‘Wai Chee’ litchi. In this study, a number of horticultural manipulation techniques were investigated with the aim of enhancing yield, fruit size and quality in ‘Wai Chee’ litchi. The use of chemical applications of foliar nutrients and plant growth regulators were found to improve certain fruit characteristics in ‘Wai Chee’. Foliar nutrient applications of nitrogen, potassium and calcium during the early stages of fruit set and -development improved fruit set and subsequently yield, and also increased fruit mass, fruit size and flesh mass. Treatments with potassium nitrate (KNOз), calcium nitrate (CaNOз) and calcium metalosate proved to be the most enhancing nutrient applications. Applications of synthetic auxins and auxin-like substances during the 2-3g stage of fruit development improved fruit size, fruit mass and flesh mass in ‘Wai Chee’. The combination treatment of Tipimon® (2,4,5-TP), applied at the 2-3g stage, followed by Maxim® (3,5,6-TPA) a week later, yielded the best results in this regard. With biological practices, pollination was found to have an influence on litchi tree- and fruit characteristics. Pollen source proved to have an influence on fruit set and fruit retention at harvest in ‘Wai Chee’. Initial fruit set was lower when using cross-pollination compared to the use of self-pollination in female flowers of ‘Wai Chee’, whereas final fruit retention was higher with the use of cross-pollinators when compared to retention of fruit with self-pollination. Although some beneficial effects with different pollen donors on fruit characteristics were observed, these effects were not significant, and would therefore necessitate further investigation. Pollen donor effect on quality parameters such as Titratable acid (TA)- and Total Soluble Solid (TSS) content of fruit was not significant. Cultivar differences regarding fruit characteristics and maturation rate were detected with the use of cultural practices such as bunch covering materials in ‘HLH Mauritius’ and ‘Wai Chee’. Beneficial effects on fruit size were obtained with thicker covering materials with nominal mass of 70 and 80 g/m² respectively on ‘HLH Mauritius’, while with ‘Wai Chee’, thinner covering materials (60 and 65 g/m²) showed enhancing effects. Maturation rate was significantly delayed only on ‘Wai Chee’ with the use of thicker covering materials (70 and 80 g/m²). Differences in colour were detected amongst different covering materials, but these should be verified with chromameter technology. Covering of fruit bunches for better fruit size and a later harvest date would, especially for ‘Wai Chee’ as a late season cultivar, be beneficial, since better prices are realised towards the end of the season.
Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

Introduction: About 80% of those affected by osteoporosis are postmenopausal women. Therefore, identifying beneficial or harmful dietary factors for postmenopausal osteoporosis may have a significant public health impact. Objectives: The overall objective of this thesis was to examine the relations between various dietary factors and bone health in postmenopausal women aged ≥ 45 years using different analytical approaches. Methods: First, the associations between fruit and vegetables (F&V) intake and indicators of bone health were assessed using a systematic review approach. Electronic databases were searched and peer-reviewed observational and interventional studies published in English with F&V intake as a main dietary exposure were included. Data selection, extraction and evaluation of risk of bias were performed independently by two reviewers. Second, the associations between an overall diet quality index (HEI-2005) and its components with bone turnover markers (BTMs) were examined. Third, the relationships between alpha-tocopherol intake, serum alpha- and gamma-tocopherol, two concentration biomarkers of vitamin E intake, and their ratio and BTMs were assessed. For the second and third studies, cross-sectional data from the National Health and Nutrition Examination Survey 1999-2002 were used. Weighted multiple regression models with adjustments for relevant confounders were used to examine the relationship between exposures and serum bone-specific alkaline phosphatase (BAP), a biomarker of bone formation, and urinary N-Telopeptides/Creatinine (uNTx/Cr), a biomarker of bone resorption. Results: There was significant between-study heterogeneity in design, definition and amount of F&V intake, outcomes, analyses and reporting of results in the eight included studies. Overall, cross-sectional and case-control analyses reported protective associations between F&V intake and bone health, whereas interventional and prospective cohort analyses did not. There were no associations between total HEI-2005 scores and BTMs. However, the Milk Group component of HEI-2005 had a significant inverse relationship with uNTx/Cr. Higher serum gamma-tocopherol and lower ratio of serum alpha- to gamma-tocopherol were associated with higher BAP concentrations but had no associations with NTx/Cr concentrations. Conclusions: The results confirm the existing knowledge that a diet with adequate intake of dairy may reduce bone loss. Further research is needed to examine the potential anabolic effects of gamma-tocopherol on bone in postmenopausal women.

博士
國立中興大學
農藝學系所
100
Researches of this study aimed to compare the nutritional, sensory qualities between organic and conventional agricultural products in subtropical Taiwan. Few studies have investigated the influences of organic and conventional production systems on commercial food products based on sub-tropical condition. In this study organic and conventional carrots (cv. Xiangyang No.2), papaya (cv. Tainung No. 2), pineapple (cv. Tainung No. 17) and two Japonica rice cultivars (cv Kaohsiung No. 139 and Taikeng No.16) were selected for the various comparative studies of maturity, quality indices and physicochemical properties of fruits and vegetables, milling and nutritional properties of rice , sensory analysis (consumer and panels) and secondary metabolites content (total phenolic compound and antioxidant activities) for rice and fruits. The organically grown fruits and vegetables appeared to contain improved and higher brix value, sugar and organic acid contents. However, except lower values in a few micronutrients (Cu and Mn), and soluble protein of studied fruits and vegetables, many parameters were improved including higher free amino acid and antioxidant activities, while lower nitrate content of the plants produced from organic farming. Similarly, some properties such as physical appearances (color intensity) and few quality indices (vitamin C and titratable acidity) were found no differences or increment due to organic farming in these fruits and vegetables. Autumn season carrot and papaya and spring harvested pineapple were reflected as suitable for consumer preference in quality and nutritional value. Though, no significant differences were evident between the organic and conventional fruits (papaya and pineapple) and rice for sensory parameters tested. Nonetheless, no significant improvement noticed in physicochemical properties of organic rice also, however starch viscosity properties were higher in organic rice. Kaohsiung No. 139 was found as better as compared to Taikeng No. 16 in nutritional properties and secondary metabolites content. Collectively, available valid evidence supports the consumer intuition that organically produced foods are superior in terms of food safety, nutritional content and value to conventionally produced foods. However, for a better and general conclusion of organic products superiority, intensive research needed in adoption of samples from more different growing conditions (farm, experimental plot, and market) and diversified agricultural products on sub-tropical region perspective to confirm the findings of this study; and to investigate, under controlled conditions, the link between organic food consumption and human health.

La transition nutritionnelle et l’insécurité alimentaire sont parmi les facteurs externes majeurs diminuant la qualité de l’alimentation. Les effets du déclin de celle-ci se résument par l’augmentation de la prévalence des maladies chroniques et des carences nutritionnelles. Afin de combattre ces problèmes, plusieurs études ont trouvé que la qualité de l’alimentation a été améliorée par l’autoproduction d’aliments (autorécolte*). Cette étude vise à identifier si un lien existe entre la qualité de l’alimentation et l’autorécolte d’aliments végétaux dans le contexte rural libanais, à partir de 748 748 répondants en provenance des régions du Chouf, Hermel et Aarsal. Afin de décrire l’alimentation selon le statut de récolte en ajustant pour différentes variables confondantes, des tests de χ2, d’ANOVA et des comparaisons multiples (Bonferroni) ont été effectués. Une interaction significative a été trouvée entre les deux types de récolte à tous les niveaux montrant que les collecteurs de plantes/fruits sauvages avaient tendance à produire domestiquement des fruits/légumes et vice versa. Le statut d’autorécolte d’aliments-sauvages avait une association positive et significative avec la variété et la fréquence de consommation à l’exception de celle des fruits et l’autorécolte domestique avait une association significativement positive avec la variété de consommation de légumes et la fréquence de consommation de fruits et légumes. Une forte association a été trouvée entre la région de résidence et les tendances de consommation de fruits/légumes. En outre, l’association entre l’autorécolte domestique et la fréquence de consommation des fruits et légumes s’est avérée positive dans la région où leur fréquence de consommation est la moins élevée (Hermel). Cette étude démontre que l'autorécolte des aliments végétaux, qu'ils soient produits dans un jardin-maison ou récoltés dans la nature, est significativement associée à une plus grande variété (diversité) et fréquence de leur consommation et que ces associations sont généralement liées à l'intensité de la récolte. Mots-clés: Transition nutritionnelle, insécurité alimentaire, autorécolte, autoproduction de fruits et légumes, collecte de plantes sauvages, variété, fréquence de la consommation alimentaire. *Dans ce document, le terme autorécolte d’aliments est utilisé pour inclure l’autoproduction et l’autocueillette d’aliments sauvages et le terme « aliments » reflète les groupes suivant : les fruits, légumes, plantes sauvages et fruits sauvages.
The nutrition transition and food insecurity are among the major external factors diminishing diet quality. The effects of diet quality decline can be summarized by the increase in the prevalence of chronic diseases and nutritional deficiencies. To combat these problems, several studies have found that diet quality has been improved by self-production of food (self-harvest*). This study aims to identify whether a link exists between diet quality and self-harvest of plant-food in the Lebanese rural context using data from 748 adult participants living in Chouf, Hermel and Aarsal. To describe dietary patterns of the study population according to the harveststatus, χ2, ANOVA and multiple comparisons (Bonferroni) were used while adjusting for various confounding variables. A significant interaction was found between the two types of harvest at all levels showing that collectors of wild plants/fruits tended to also have some domestic production of fruits and vegetables, and vice versa. While wild-food harvest had a significant positive association with the variety and frequency of consumption except for fruit consumption frequency, domestic harvest had a significantly positive association with vegetable consumption variety and fruit and vegetable consumption frequency. A strong association was found between the region of residence and fruit/vegetable consumption trends. Moreover, the association between domestic harvest and fruit/vegetable consumption frequency was only positive in the region where the consumption frequency was lowest (Hermel). This study demonstrates that self-harvesting of plant foods, whether produced in a home garden or collected from the wild, is significantly associated with greater consumption variety (diversity) and frequency of these foods and that these associations are generally related to the intensity of harvesting. Keywords: Nutrition transition, food insecurity, self-harvest of food, self-production of fruits and vegetables, wild plant harvest, food consumption variety, food consumption frequency. * In this document, the term self- harvest used to include the self-production of food and wild food collection. The term "food" reflects the following groups: fruits, vegetables, wild plants and wild fruits.