Rozprawy doktorskie na temat „Beverages”

The beverage industry is tending towards the production of healthier, low calorie beverages containing only naturally derived ingredients. The use of these ingredients presents an opportunity for a rise in functional beverages but could also present beverage quality challenges. Using Hibiscus sabdariffa (Roselle) extracts, known for its functional properties, this research investigates some quality considerations that may result due to relevant changes to the production, storage and consumption of the beverage to suit clean label considerations. These issues relate to processing, calories reduction and stability. Several research questions have been generated under these categories and addressed in subsequent chapters of the thesis. From a Roselle beverage perspective, pasteurisation (in-bottle, 85oC for 20 minutes) and cold storage (below 4oC) were satisfactory for processing of the beverage. Stevia Rebaudioside A (SRA) was explored as a sugar replacer and displayed promising results such as improving the sensory attributes of the unsweetened Roselle extract. In physical and chemical tests, it matched the attributes of unsweetened beverages. However, it did not perform as well as sugar in either consumer studies and when combined with spice flavours. The spices (cinnamon, ginger and cloves) used for their flavouring and preserving properties did not improve consumer liking of the beverages in general but cinnamon demonstrated stabilising effects on the anthocyanins in a sugar sweetened Roselle beverage through a suspected co-pigmentation mechanism. Furthermore, cinnamon and ginger were deemed congruent with the Roselle flavour profile based on their performance in the consumer study. Further investigative work on spice and sweetener synergies and the understanding of their mechanisms were recommended.

Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2016.
This study focused on alcoholic fermented fruit beverages that were produced from various types of fruit, value addition and thus potentially increasing the diversity of commercially available fruit wines. Non-grape alcoholic fermented fruit beverages is a complex mixture of water, alcohol, and other components, that are either initially present in the fruit, or are formed during the fermentation process. The evaluation of wine and similar fermented products quality is important for manufacturers and consumers. The routine analysis of alcoholic fermented fruit beverages acts as an important tool that is useful for wine classification, quality control and sensory evaluation. Therefore, the aims of this study were (1) to measure methanol, ethanol, titratable acidity, objective colour, total soluble solids and sensory profile as a function of yeast strain and percentage pulp in order to adapt existing technologies toward producing new fermented fruit beverage products using plums, an under-utilized agricultural produce; and (2) to measure methanol, ethanol, titratable acidity, objective colour, total soluble solids and sensory profile as a function of yeast strain, pulp percentage and sugar levels in order to adapt existing technologies toward producing new fermented fruit beverages based on red and white wine styles, while applying the technology developed in the first part of the study using red-fleshed plums, blueberries and blackberries. The independent variables (ID) were yeast strains (1) Saccharomyces cerevisiae VIN13, (2) Saccharomyces cerevisiae NT116, and (3) Saccharomyces bayanus N96, with formulations containing percentage pulp concentrations at (40%, 50% and 60%). The dependent variables (DV) constituted key quality parameters for white and red wine style, namely methanol, ethanol, titratable acidity, objective colour, total soluble solids, pH and sensory profile were measured. The optimal combination of independent variables was ascertained and in terms of the overall consumer response, for the red-fleshed plum beverage sample treatment N 96, 60% pulp showed the highest preference amongst consumers. In terms of the other dependent variables, namely methanol, ethanol, titratable acidity, objective colour, total soluble solids, pH and sensory profiles of alcoholic fermented fruit beverages based on white and red wine styles. The processing conditions developed and applied in this study towards the development of alcoholic fermented beverages utilizing plums and selected berries demonstrated ways of improving the utilization of fruit commodities by developing niche products. Hence, the development of alcoholic fermented beverages utilizing (plums and selected berries) showed potential for micro agro-industries, as well as the impact on its potential role in employment creation and income generation.

Food and beverage marketing influences the preferences and diet quality of adolescents. In 2009, about one third (23.8 million US dollars) of the 77 million US dollars spent on celebrity marketing targeted to American adolescents promoted sugar-sweetened beverages (SSB) associated with obesity and type 2 diabetes. Research is limited on how celebrity endorsement influences adolescents' SSB choices and intake. This M.S. thesis describes a study with three research objectives conducted among 28 adolescents in Virginia to explore their beverage intake and views about celebrity endorsement of beverage products. Participants completed four activities including: BEVQ-15 to determine the type and amount of beverages consumed; a familiarity survey with 48 celebrities and their endorsements for six beverage product categories; Q methodology study that used 48 celebrity images depicting beverage brand and product endorsements where participants sorted the images on a normal distribution (+4 to -4) based on perceived celebrity credibility (i.e., expertise, attractiveness and trust); and a post Q sort questionnaire. The BEVQ-15 revealed that 96.3% of participants did not adhere to healthy beverage guidelines. A majority of participants recognized between 51% and 75% of the celebrities, but only 4.9% accurately identified celebrities and their associated beverage endorsement category. The Q methodology study used factor analysis to identify three unique viewpoints: (1) entertainment image emulators; (2) inspirational celebrities for perceived healthier beverages; and (3) multi-cultural celebrity appreciators. Study results may inform future policies and actions to ensure that celebrity endorsement encourages adolescents to buy and consume healthy beverages that align with guidelines.
Master of Science

Riboflavin, also known as vitamin B2 and one of the most easily absorbed nutrients,can be found in many different organisms. The most abundant source of riboflavin ismilk and dairy products; however it is also present in meat, fish and certain types ofvegetables and fruit. Riboflavin is an important part of a healthy diet in order to keep skin, eyes and nervous systems healthy. Some studies indicate that riboflavin plays an important role in cancer and cardiovascular diseases.As known, milk is extremely sensitive to light. Riboflavin is one of the factorsresponsible for the light-induced degradation of milk. In combination with light andoxygen riboflavin may act as a photosensitizer. When vitamin B2 absorbs blue-greenlight, an excited triplet state of riboflavin is generated through a process called intersystem crossing. Reactive oxygen species, such as singlet oxygen, is then formed by reaction of excited riboflavin triplet with dissolved oxygen present in milk. Light exposure of milk can lead to off-flavor and damage of vitamins by reaction of singlet oxygen with amino acids and lipids in milk. Unfortunately, most of the packaging materials today do not protect milk from light completely. The formation of singlet oxygen can also be prevented by adding quenchers that are able to deactivate riboflavin triplets.Certain amino acids and carotenoids are well known flavin quenchers.The purpose of this study was to investigate how well riboflavin triplets can bequenched by amino acids cysteine, histidine, methionine, tyrosine and tryptophan. Thequenching properties of hydrophilic carotenoid crocin were studied as well. Crocinhas been under investigation of researches at the Departement of Physics at NTNU.Lumiflavin, which is one of the riboflavin’s photodegradation products, was used instead of riboflavin. The former is more stable and has similar photochemical characteristics as the latter.The quenching of lumiflavin triplets was studied by using laser flash photolysis. Itconsists of irradiating the sample under investigation with a short-lived laser flash. The method was used to measure the kinetic decay rate of lumiflavin in aqueous buffer with and without different concentrations of a quencher. The data were fitted to two different decay models. From pseudo-first-order rate constants the quenching rate constants were determined for each amino acid and crocin. All amino acids and crocin used in this study showed a quenching effect on the lumiflavin triplets. Further, it was determined whether the fitting models are suitable for these kind of measurements by simulating the decay of lumiflavin with and without any quencher. More studies on the fitting models have to be done to be able to get reliable results.

Attention on beverage intake, specifically sugar-sweetened beverages (SSB), has increased in recent years (1). Energy-containing beverages do not provide the same satiety as solid foods, and intake of solid food is not spontaneously reduced when energy-containing beverages are consumed (2,3). This may contribute to positive energy balance (1). Conversely, a reduction in energy intake occurs by replacing SSB with water and may facilitate weight loss (4,5). A valid, reliable and sensitive assessment tool for quantifying beverage consumption and determining its influence on weight status could help advance research on this topic. Three studies were conducted to develop the BEVQ, a self-administered quantitative beverage intake questionnaire. First study (n=105): the 19-item BEVQ's validity was examined by comparing participant's beverage intake to the "gold standard" of dietary intake assessment, food intake records; reliability was assessed by comparing two BEVQ's, administered two weeks apart. The BEVQ demonstrated acceptable validity (R2=0.53, water g; 0.46, 0.61 total beverage g, kcal; 0.49, 0.59 SSB g, kcal) as well as reliability (all correlations P<0.001) (6). Second study (n=1,596): the BEVQ underwent exploratory factor analyses (EFA) to identify the potential to reduce items. Three beverage items, which contributed <10% to total beverage intake g, kcal, were eliminated; EFA identified beer and light beer as a combined category. The refinement led to the 15-item BEVQ, which produced a lower readability score of 4.8 and shorter administration time (~2 min) (7). Third study (n=70): the ability of the BEVQ-15 to detect changes in beverage intake was evaluated by increasing participant water and fruit juice consumption and evaluating BEVQ-15 outcomes before and after the feeding period. Increases in water, juice and total beverage (g) were detected during the intervention period (P<0.001) (8). This rapid, valid, reliable and sensitive beverage intake assessment tool may determine the habitual intake of SSB and other beverages, and evaluate the effectiveness of clinical and public health interventions which aim to address national SSB recommendations. Future work is needed to evaluate the validity and reliability of the BEVQ-15 in children, as well as develop cost-effective noninvasive biomarkers that can objectively estimate intake of specific foods/dietary components (9).
Ph. D.

This study analyzes the economic and demographic drivers of household demand for at-home consumption of nonalcoholic beverages in 1999. Drivers of available intake of calories, calcium, vitamin C, and caffeine associated with the purchase of nonalcoholic beverages also are analyzed. The 1999 ACNielsen HomeScan Panel, purchased by the U. S. Department of Agriculture, Economic Research Service, is the source of the data for this project. Many different classifications of beverages were analyzed including milk(whole, reduced fat, flavored, and non-flavored), regular and low-calorie carbonated soft drinks, powdered soft drinks, isotonics(sports drinks), juices(orange, apple, vegetable, and other juices), fruit drinks, bottled water, coffee(regular and decaffeinated), and tea(regular and decaffeinated). Probit models were used to find demographic drivers that affect the choice to purchase a nonalcoholic beverage. Heckman sample selection models and cross tabulations were used to find demographic patterns pertaining to the amount of purchase of the nonalcoholic beverages. The nutrient analysis indicated that individuals receive 211 calories, 217 mg of calcium, 45 mg of vitamin C, and 95 mg of caffeine per day from all nonalcoholic beverages. A critical finding for the nutrient analysis was that persons within households below 130% of poverty were receiving more calories and caffeine from nonalcoholic beverages compared to persons within households above 130% of poverty. Likewise, persons in households below 130% of poverty were receiving less calcium and vitamin C from nonalcoholic beverages compared to persons in households above 130% of poverty. Price and cross-price elasticities were examined using the LA/AIDS model. Methodological concerns of data frequency, beverage aggregations, and censoring techniques were explored and discussed. Own-price and cross-price elasticities for the beverages were uncovered. Price elasticities by selected demographic groups also were investigated. Results indicated that price elasticities varied by demographics, specifically for race, region, and presence of children within the household. The information uncovered in this dissertation helps to update consumer demand knowledge and nutritional intake understanding in relation to nonalcoholic beverages. The information can be used as a guide for marketing strategists for targeting and promotion as well as for policy makers looking to improve nutritional intake received from nonalcoholic beverages.

The mouthfeel and texture of food and beverage products play an important role in consumer liking. However, to date these key sensory properties have received limited attention from researchers and our understanding of texture and mouthfeel perception in food remains restricted. For tea, a popular beverage enjoyed around the globe, astringency is the most frequently highlighted mouthfeel attribute. Since black tea is commonly consumed with milk and sugar, research investigating the mouthfeel of tea as impact by these added ingredients is of commercial interest. The aim of this PhD research was to gain a better understanding of the mouthfeel perception of black tea beverages using sensory and instrumental methods. In order to achieve this, a model system consisting of black tea instant powder, sugar, and fat (added as oil-in-water emulsion) was developed which allowed for the independent variation of the design factors (tea, sugar, fat). Firstly, a mouthfeel lexicon was developed using Quantitative Descriptive Analysis (QDA), and the impact of tea, sugar and fat on the perception of selected attributes was assessed by a trained panel (n=10) using a Design of Experiments approach to generate predictive polynomial models from a D-optimal design. Furthermore, the temporal perception of astringency and bitterness over multiple sips of tea was assessed by a trained panel(n=9) using Time Intensity measures. The effect of sweetness and viscosity from sucrose was decoupled using sweeteners and thickeners and the effect of sugar on astringency and bitterness perception was investigated in more detail. Once the mouthfeel perception of black tea beverages was explored, instrumental methods were deployed to reveal possible correlations between instrumental parameters and mouthfeel perception. Two instrumental methods were used: a force plate to measure the frictional and vibrational behaviour of tea samples, whilst an accelerometer was used to measure vibrations related to tongue movements using a technique called “acoustic tribology”. The results showed that besides astringency, fat-driven attributes, such as “thickness”, “slipperiness” and “mouth coating”, play a significant role in the mouthfeel perception of black tea beverages. Predictive polynomial models revealed the complex effects of key ingredients on the mouthfeel of tea. The results showed that tea was not a significant factor (p > 0.05) for the attributes “thickness” and “mouth coating”, whereas for all other attributes all three design factors affected perception significantly (p < 0.001). It was found that astringent and bitter intensity was reduced by the addition of fat and sugar in a similar fashion. However, when evaluated over time, it was found that astringency and bitterness had distinctly different temporal profiles in tea, illustrating the importance of temporal ratings. A build-up in astringency and bitterness intensity with increasing number of sips gave further insight into the perception of both attributes during tea consumption, representing a normal tea drinking behaviour. Furthermore, the data indicated that sugar reduces astringency due to its sweetness and not the rise in viscosity. The results from the force plate experiment showed that the addition of 5% fat significantly reduced the friction coefficient of tea samples (p < 0.0001) and that an addition of 10% fat did not reduce the friction coefficient further (p=0.97). It was also shown that the friction coefficient did not vary significantly between tea levels (p=0.324). The results also revealed that fat-driven attributes were negatively correlated to friction and that astringency was a complex precept, which was difficult to predict using instrumental methods, resulting in a poor correlation between friction coefficient and astringency (R2=0.16). The results from the “acoustic tribology” experiment indicated that mouthfeel was linked to measured vibrations caused by tongue movements. Furthermore, differences in tea composition resulted in different oral vibrations, and it was observed that for example “thick” is positively correlated to low frequency vibrations. The results of this research on the perceived mouthfeel of tea provide much needed insight into this key sensory property of tea. These results will be further useful for product developers interested in producing ready-todrink tea beverages where mouthfeel is likely to be a critical factor for consumer liking and commercial success.

Thesis (Ph. D.)--Georgia State University, 2006.
Includes vita. Title from title screen. Shiferaw Gurmu, committee chair; Paula E. Stephan, Erdal Tekin, Gregory B. Lewis, committee members. Electronic text (259 p.). Description based on contents viewed May 9, 2007. Includes bibliographical references (p. 250-258).

Thesis (MPH) -- University of Limpopo, 2012.
Background: Over the last few decades, soft drink consumption has been steadily increasing especially at an alarming rate among adolescents. Soft drinks have been associated with positive energy intake. An unhealthy diet along with a lack of physical activity is a major risk factor for health problems like overweight and obesity, cardiovascular diseases and diabetes. Children and adolescents are becoming very susceptible to the development of NCDs due to an increase in consumption of heavily processed and highly caloric foods, leading to early onset of morbidity. Aim of the study: To investigate soft drink consumption among grade 11 and 12 learners at a secondary school in Gauteng, South Africa Methods: A quantitative descriptive survey was conducted among 382 learners (grade 11 and 12) of Liverpool secondary school. A self-administered questionnaire was used to collect data. STATA version 10 was used for data entry and analysis. Results: All learners who participated in the survey reported that they consumed soft drinks over the past 12 months. Out of the 382 learners, only 55 (14.4%) were non-frequent consumers. Carbonated drinks were the most commonly consumed (73.6%). Factors such as frequent snacking (p=0.042), frequent fast food consumption (p=0.001) and easy availability of soft drinks (p=0.00) positively influenced the consumption of soft drinks. Over 55% of the learners had very poor knowledge about the health effects caused by increased consumption of soft drinks. Conclusion: In line with the high consumption of soft drinks, the level of awareness of the health effects of these unhealthy dietary practices among the learners in this study is very poor. Interventions to improve good or healthy dietary habits have to be started both at the home and school level.

The former finance minister stated in his budget speech in 2016 that sugar tax would come into force in South Africa from 1 April 2017. The treasury's reason for implementing sugar taxation is to reduce the health problems caused by sugar. It is nothing new to use fiscal measures to recover both taxes and to prevent health problems but it was not yet possible to reach a definite conclusion about the impact of sugar tax on the consumption of sugary drinks and the prevalence of obesity. The reason for this is that there is evidence that the implementation of food tax in different countries has shown different results in terms of public health issues and tax benefits. In South Africa, the implementation of sugar tax can either reduce the prevalence of obesity and thereby have a positive effect on the economy or its implementation may adversely affect the economy. If treasury does not implement sugar tax the economy can also be adversely affected by the prevalence of obesity. This dissertation deals with the effects of non-communicable diseases and sugar tax on the South African economy. The focus is on how sugar tax is being implemented internationally and how South Africa intends to implement sugar tax.
Die voormalige minister van finansies het in sy begrotingstoespraak in 2016 vermeld dat suikerbelasting vanaf 1 April 2017 in Suid-Afrika in werking gaan tree. Die tesourie se rede vir die implementering van suikerbelasting is om, in samewerking met die Departement van Gesondheid, die gesondheidsprobleme wat deur suiker veroorsaak word te verminder. Dit is niks nuuts om fiskale maatstawwe te gebruik om beide belasting in te vorder en gesondheidsprobleme te voorkom nie, maar dit was nog nie moontlik om tot ’n definitiewe gevolgtrekking te kom oor die impak van suikerbelasting op die verbruik van suikerversoete drankies en die voorkoms van vetsug nie. Die rede hiervoor is dat daar bewyse is dat die implementering van voedselbelasting in verskillende lande verskillende resultate getoon het in terme van openbare gesondheidskwessies en belastingvoordele. In Suid-Afrika kan die implementering van suikerbelasting óf die voorkoms van vetsug verminder en sodoende die ekonomie bevoordeel óf die implementering daarvan kan die ekonomie negatief beïnvloed. Indien die tesourie nie suikerbelasting implementeer nie kan die ekonomie as gevolg van die voorkoms van vetsug negatief beïnvloed word. Die kern van hierdie skripsie handel oor die gevolge van nieoordraagbare siektes en suikerbelasting op die Suid-Afrikaanse ekonomie. Daar word spesifiek gefokus op hoe suikerbelasting internasionaal geïmplementeer word en hoe Suid-Afrika beoog om suikerbelasting te implementeer.
Mini Dissertation (LLM)--University of Pretoria, 2017.
Mercantile Law
LLM
Unrestricted

Evidence for higher intakes of sugar-sweetened beverages (SSBs) driving the risks of obesity, type 2 diabetes and cardiovascular disease is increasing. As a result, SSBs have been targeted across public health interventions worldwide, including Mexico, which has one of the highest levels of consumption of SSB and alarmingly high childhood obesity rates. This thesis aimed to determine the effectiveness of interventions and intervention’s components to reduce consumption of SSBs and to develop and implement an intervention in school-aged children in central Mexico. A systematic review and meta-analysis was undertaken to examine the impact that interventions have had to reduce SSB intake or increase water intake across all age groups. Identification and analysis of behavior change techniques used in interventions was also undertaken. Exploratory analyses on data from children in central Mexico indicated that 12% of 6 to 15 year olds met criteria for Metabolic Syndrome. Consequently, a 12-week school-based programme was developed to influence consumption of SSB through promotion of water intake. Sixteen classes in four schools were allocated to the intervention group (N= 2 schools, 8 classes) or control group (N= 2 schools, 8 classes). Participants were 337 children aged 7-12 years (222 in intervention and 115 in controls). Pooled estimates from meta-analyses indicated that interventions modestly influence SSB intakes in children (-92 mL/day (95% confidence interval [CI] -145 to -39) 18 studies, P < 0.01) but not in adolescents (-52 mL/ day, 95% CI -121 to 17; 4 studies, P = 0.14) or in adults (-23 mL/day, 95% CI -56 to 9; 7 studies, P = 0.16). Pooled estimates of water intakes were only possible for interventions in children and these were indicative of increases in water intake (MD +80 mL/day, 95% CI 6 to 155; 6 studies, P = 0.04). There was some evidence to suggest model/demonstrating the behaviour or parental involvement helped to reduce SSB intake. Results from the study in Mexico highlighted that intervention and control groups achieved reductions in daily intake of SSB by -61 mL/day and -132 mL/day, respectively, with the difference between groups not being statistically significant (71 mL/day; 95% CI: 94 to 236; p=0.4). Consumption of water throughout the day decreased in both groups (Intervention: -169 mL/day; 95% CI: -275 to -62 vs controls: 235 mL/day; 95% CI: -369 to -102). Information from a process evaluation highlighted difficulties in children and staff to deliver and adhere to activities as planned. In conclusion, community-level interventions can influence positive changes in consumption of SSB in children but not in adolescents or adults; an educational and environmental approach focusing on the promotion of water intake in Mexican children was insufficient to improve consumption patterns of SSB and water. Interventions in the future could potentially be benefitted by longer implementation as well as parental involvement.

La perception des emballages alimentaires est passée d’utile à source majeure de contaminants dans les aliments et menace pour l’environnement. La substitution du verre par des con-tenants en plastiques recyclés ou biosourcés réduit l’impact environnemental des boissons embouteillées. La thèse a développé de nouveaux outils de simulation 3D et d’optimisation pour accélérer le prototypage des emballages éco-efficaces pour les boissons alcoolisées. La durée de conservation des boissons, la sécurité sanitaire des matériaux plastiques recyclés, les contraintes mécaniques, et la quantité de déchets sont considérées comme un seul problème d'optimisation multicritères. Les nouvelles bouteilles sont générées virtuellement et itérativement en trois étapes comprenant : i) une [E]valuation multiéchelle des transferts de masse couplés ; ii) une étape de [D]écision validant les contraintes techniques (forme, capacité, poids) et réglementaires (durée de conservation, migrations); iii) une étape globale de ré[S]olution recherchant des solutions de Pareto acceptables. La capacité de prédire la durée de vie des liqueurs dans des conditions réelles a été testée avec succès sur environ 500 miniatures en PET (polyéthylène téréphtalate) sur plusieurs mois. L’ensemble de l’approche a été conçu pour gérer tout transfert de matière couplé (perméation, sorption, migration). La sorption mutuelle est prise en compte via une formulation polynaire de Flory-Huggins. Une formulation gros grain de la théorie des volumes libres de Vrentas et Duda a été développée pour prédire les propriétés de diffusion dans les polymères vitreux de l’eau et des solutés organiques dans des polymères arbitraires (polyesters, polyamides, polyvinyles, polyoléfines). 409 diffusivités issues de la littérature ou mesurées ont été utilisée pour validation. La contribution de la relaxation du PET vitreux a été analysée par sorption différentielle (binaire et ternaire) de 25 à 50 °C. Une partie du code source sera partagé afin d'encourager l'intégration de davantage de paramètres affectant la durée de conservation des boissons et des produits alimentaires (cinétique d'oxydation, piégeage d'arômes)
The view of plastic food packaging turned from useful to a major source of contaminants in food and an environmental threat. Substituting glass by recycled or biosourced plastic containers reduces environmental impacts for bottled beverages. The thesis developed a 3D computational and optimization framework to accelerate the prototyping of eco-efficient packaging for alcoholic beverages. Shelf-life, food safety, mechanical constraints, and packaging wastes are considered into a single multicriteria optimization problem. New bottles are virtually generated within an iterative three steps process involving: i) a multiresolution [E]valuation of coupled mass transfer; ii) a [D]ecision step validating technical (shape, capacity, weight) and regulatory (shelf-life, migrations) constraints; iii) a global [Solving] step seeking acceptable Pareto solutions. The capacity to predict shelf-life of liquors in real conditions was tested successfully on ca. 500 hundred bottle min iatures in PET (polyethylene terephthalate) over several months. The entire approach has been designed to manage any coupled mass transfer (permeation, sorption, migration). Mutual sorption is considered via polynary Flory-Huggins formulation. A blob formulation of the free-volume theory of Vrentas and Duda was developed to predict the diffusion properties in glassy polymers of water and organic solutes in arbitrary polymers (polyesters, polyamides, polyvinyls, polyolefins). The validation set included 433 experimental diffusivities from literature and measured in this work. The contribution of polymer relaxation in glassy PET was analyzed in binary and ternary differential sorption using a cosorption microbalance from 25 to 50°C. Part of the framework will be released as an open-source project to encourage the integration of more factors affecting the shelf-life of beverages and food products (oxidation kinetics, aroma scalping)

Concomitant with the obesity epidemic, the consumption of sugar-sweetened beverages (SSBs) has increased over the same period. There is an increasing debate as to the potential association between SSB consumption and obesity. Recommendations to limit SSB consumption have been widely acknowledged. Finding suitable beverage alternatives for SSBs may be particularly beneficial in reducing SSB consumption and curbing its associated health outcomes. However, evidence on the long-term effects of replacing SSBs with other beverage types is sparse. By using an epidemiological approach, the current thesis aimed to examine the associations between SSB consumption, the substitution of SSBs by other beverage types, and long-term changes in obesity outcomes in cohorts of Danish and Australian children. Analyses were undertaken in three datasets: the European Youth Heart Study, the Childhood Asthma Prevention Study, and the Healthy Start Study. Multivariate linear regression models were used to assess associations between SSB consumption and changes in obesity outcomes. Substitution models were performed to evaluate the association between substitutions of SSBs with other beverage types on obesity outcomes. Positive associations of SSB consumption and long-term changes in obesity outcomes were consistently found in all three cohorts. Significant associations between substitutions of SSBs by water, milk, or artificially-sweetened beverages with obesity outcomes were also revealed. Results of the current thesis confirm a positive association between SSB consumption and increases in long-term obesity outcomes in prospective cohorts of Danish and Australian children. Moreover, water, milk or artificially-sweetened beverages were found to be better alternatives for SSBs in regard to obesity development. The findings of this thesis are particular relevant for health researchers and policy makers in delivering practical recommendations towards SSB consumption and obesity prevention.

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Traditionally brewed beers are of cultural and economic importance to many African nations. The presence of mycotoxins in African beer is a topic that needs to be addressed, since most African countries have a climate of high humidity and temperature that favours the growth of moulds. Mycotoxins challenge not only the health of animals and humans, but also the economy, especially in underdeveloped countries where contamination is most likely. Literature proves that mycotoxins depict various effects on the immune system including immunotoxicity. Beer analysis is therefore of utmost importance in order to evaluate organoleptic characteristics, quality, nutritional value as well as safety. The aims of this study involve the analysis and comparison of traditional and commercial beer in terms of physical characteristics, mycotoxin concentrations as well as effects on specific immune pathway biomarkers in order to elucidate possible immunotoxicity..."

Thesis (PhDAgric (Viticulture and Oenology. Wine Biotechnology))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: Stuck alcoholic fermentations are a major enological problem for the international winemaking industry. Incomplete wine fermentations are frequently characterized by high residual fructose concentrations and the near-absence of residual glucose, a fact that is due to the glucophilic character of the wine yeast Saccharomyces cerevisiae. Wines with high contents of post fermentation sugar are very susceptible for microbial spoilage since residual fructose and/or glucose can be metabolized by bacteria and yeast to undesired by-products such as volatile acid and off-flavours, resulting in wine spoilage and considerable economic losses. It has been reported that stuck fermentations are usually caused by several synergistically acting inhibition factors, and the glucose to fructose ratio (GFR) is thought to play an important role in this context. This study is aimed at contributing towards a better understanding of this industrial problem, and at finding industrially applicable solutions. In a first part, this study describes the isolation of two appropriate strains of the fructophilic yeast Zygosaccharomyces bailii from the natural microflora of grapevine, followed by trials in small scale test fermentations using stuck industrial fermentations as model media. These experiments were expanded to also investigate large scale industrial fermentations. As a result, a strategy for the treatment of stuck fermentations was developed and successfully applied in several wineries with fermentation problems. This methodology represents an entirely novel and industrially applicable solution to high residual fructose levels. In a second part, the data contributes to elucidating the molecular nature of the fructophilic phenotype of Z. bailii by characterizing some of the genes and proteins that may be responsible for the fructophilic character. In particular, the investigation focused on the first two steps of hexose metabolism, the transport of sugar into the cell by permeases and sugar phosphorylation by hexokinases, which combined are thought to be primarily responsible for sugar preference. One result of this study was Fructoferm W3©, a dry yeast product which is commercially available. Fructoferm W3 was awarded with the innovation medal for enological products at Intervitis/Interfructa, Stuttgart, Germany in 2007.
AFRIKAANSE OPSOMMING: Die voorkoms van steek alkoholiese fermentasies is ‘n ernstige problem in die internasionale wyn industrie. Onvolledige fermentasies word dikwels gekenmerk deur hoë residuele fruktose konsentrasies en die veitlike afwesigheid van residuele glukose. Die kenmerke kan meestal toegeskryf word aan die glukofilliese kakakter van die wyngis Saccharomyces cerevisiae. Wyne met ‘n hoë suiker inhoud na die afloop van fermentasie is vatbaar vir mikrobiese bederf aangesien residuele fruktose en/of glukose gemetaboliseer kan word deur bakterië en gis om ongewenste byprodukte soos vlugtige sure en bygeure te vorm wat kan lei tot wyn bederf en aansienlike ekonomies verlies. Dit is vasgestel dat steek fermentasies gewoonlik veroorsaak word deur verskeie sinergisties werkende inhibisie faktore, waartoe die glukose/fruktose verhouding ‘n noemenswaardiege bydrae lewer. Die mikpunt van hierdie studie was om ‘n bydrae te lewer tot die begrip van steek fermentasies en die daarstelling van moontlike industriële oplossings. Die eerste deel van die werk beskryf die isolasie van twee rasse van die gis Zygosaccharomyces baillie uit die natuurlike wingerd mikroflora, gevolg deur steekproewe in die vorm van kelinskaalse fermentasies met steek industriële fermentasies gebruik as model media. Hierdie ekserimente is vervolgens uitgebrei om grootskaalse industriële steek fermentasies te bestudeer. Die uitkoms van hierdie werk het gelei tot die ontwikkeling van ‘n strategie vir die behandeling van steek fermentasies wat susksesvol toegepas is in verskeie wynmakerye. Die metodiek bring ‘n nuwe en industrieel toepasbare oplossing vir hoë residuele fruktose vlakke. Die data aangebied in die tweede afdeling dra by tot die verheldering van die molekulêre natuur van die fruktofilliese fenotipe van Z. baillie deur die tipering van gene en protiëne wat moontlik verantwoordelik is vir die fruktofilliese karakter van die gis. Die ondersoek het spesifiek op die eerste twee stappe van heksose metabolisme, naamlik die invoer van suiker in die sel deur permeases en suiker fosforilering deur heksokinases, gekonsentreer. Die kombinasie van die twee prosesse is vermoedelik verantwoordelik vir die regulering van suiker voorkeur. ‘n Gevolg van die studie was die ontwikkeling van ‘n droë gisproduk, Fructferm W3©, wat kommersieel beskikbaar gestel is. Fructoferm W3 is in 2007 toegeken met die innovasie medalje vir wynkundige produkte by Intervittis/Interfructa in Stuttgart, Duitsland.

Práce analyzuje finanční výkonnost společnosti Coca-Cola Beverages Česká republika z pohledu externího analytika. Pro hodnocení jsou použity všechny vhodné metody finanční analýzy, tj. rozbor absolutních ukazatelů, analýza poměrovými ukazately a aplikace ukazatele ekonomické přidané hodnoty (EVA). Dále je finanční situace podniku porovnána s jeho největšími konkurenty na trhu (General Bottlers a Kofola).

The aim of my thesis was to analyze and identify main types of risks and uncertainties, which can be faced by international companies. I also described main ways and methods of avoidance and minimisation of such risky situations. AB Inbev was chosen as an example since I was working in the branch of this company located in Prague, Czech Republic. This explains my concentration mainly on the market for beverages.

Cola beverages are often made available to competitors during endurance sporting events. This thesis describes a series of investigations examining the frequency and possible physiological consequences of cola beverage use by trained endurance athletes. An initial field study assessed the knowledge, prevalence and quantity of caffeine use by athletes competing at the 2005 Ironman® Triathlon World Championships. A large majority (89%) of athletes were planning on using a caffeinated substance immediately prior to or throughout the race and a similarly high proportion (78%) indicated that cola would be one source of this caffeine. Results also indicated a trend towards greater caffeine use in those athletes aware of its recent removal from the World Anti-Doping Agency’s (WADA) prohibited substances list. The first laboratory based study investigated the ergogenic impact of changing to a cola flavoured beverage during the later stages of an endurance cycling task as. Results demonstrated that changing to a cola flavoured, but ingredient matched beverage, or an alternative flavoured sports drink following prolonged exposure to one sports drink flavour did not affect subsequent cycling time trial performance, perception of effort or perceived ratings of gastrointestinal function. These findings suggest that flavour–mediated mechanisms do not coThe final laboratory study investigated the dose-response effects of 1.5 and 3 mg∙kg-1 body weight (BW) of caffeine on exogenous CHO oxidation, and performance during endurance exercise. Again, no significant time trial performance improvements were observed during either caffeine containing trial. Additionally, when glucose was consumed in sufficient amounts to optimise its gastrointestinal absorption the addition of caffeine at either low or moderate doses did not further enhance the subsequent oxidation of this CHO.ntribute to the ergogenic potential of cola beverages consumed throughout endurance-exercise.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Public Health
Griffith Health
Full Text

Over the past several decades, the prevalence of overweight and obesity has increased to 68% of American adults1. During this same time period, there has been an increase in sugar-sweetened beverage consumption. This increase in added sugar consumption, particularly from sugar-sweetened beverages, has been theorized as a possible contributor to the obesity epidemic2,3,4. Sugar-sweetened beverages are the number one source of added sugars in the American diet and organizations such as the American Heart Association have addressed this issue of added sugar consumption due to its association with negative health outcomes5. A variety of demographic factors have been linked to increased added sugar consumption6. Health literacy is another variable which may influence beverage consumption patterns, specifically sugar-sweetened beverage consumption. To date only one study has investigated this association, and the authors reported an inverse relationship between health literacy scores and sugar-sweetened beverage consumption7. Therefore, the purpose of this investigation was to determine what demographic variables serve as predictors of consumption of sugar-sweetened beverages, water, milk, and total beverage calories. This could allow for appropriate interventions to be developed targeting healthier beverage consumption patterns in specific sub-populations.
Master of Science

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Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Control de calidad sensorial de bebidas alcohólicas utilizando rápidos sensores químicos
En la presente tesis Doctoral, han sido aplicados dos sensores artificiales para el análisis de
bebidas alcohólicas: la nariz electrónica basada en la espectrometría de masas (MS) y la lengua
electrónica basada en la espectroscopía infrarroja con transformada de Fourier (FTIR). El
propósito fue desarrollar nuevas estrategias para analizar la autenticidad de estos productos,
desde un punto de vista sensorial, por medio de técnicas las espectrales antes mencionadas.
Adicionalmente, ha sido utilizado un espectrofotómetro UV-visible como ojo electrónico. El
trabajo presentado pretende ser un avance significativo hacia el desarrollo de un catador
electrónico mediante la fusión de los tres sensores químicos: nariz electrónica, lengua
electrónica y ojo electrónico.
Sensory quality control of alcoholic beverages using fast chemical sensors
In the present Doctoral Thesis, two chemical artificial sensors are applied to the analysis of
alcoholic beverages: the Mass Spectrometry (MS)-based electronic-noses and Fourier
transform infrared (FTIR)-based electronic-tongue. The aim was developing new strategies to
test the authenticity of these products, from a sensory point of view, by means of the spectral
techniques above mentioned. Additionally, has been used an UV-visible spectrophotometer as
electronic eye. The work presented wants to be a significant advance towards the development
of an electronic taster through the fusion of three chemical sensors: electronic nose, electronic
tongue and electronic eye.

Background Dental caries on primary and permanent teeth is a common chronic disease worldwide with negative effects on children`s quality of life, both in the present and future. Sugar intake is a risk factor for caries. However, the association between sugar-sweetened beverages (SSBs) and dental caries is unclear. Methods A systematic review of relevant literature was performed in PubMed, Cochrane Library and ScienceDirect to locate every journal article in English assessing the association between SSBs and dental caries up to May 2014. Quality assessment criteria were formed by 10 essential items in STROBE statement. Results Fourteen studies were included in the present review, of which 11 were cross-sectional studies and 3 were cohort studies. Study participants were recruited from dentistry units, schools or communities. Interview-based or self-reported questionnaires for parents or caregivers were measurement tools for exposure variables. Clinical/dental examination was used to assess the outcome variables in participating children. Decayed, missing, and filled system was used among studies to record caries status. Sources of potential bias may be measurement on exposure and outcome as well as sources and methods of participants selection. Confounding existed due to nature of observational study and possible confounders included age, gender, education and location of children as well as socioeconomic position and oral health awareness of parents. Synthesis of results suggested that there may be a positive association between SSBs and dental caries, providing evidence for policymaking and recommendations for further studies. Conclusions Sugar-sweetened beverages intake could be considered as positively associated with childhood dental caries. Prevention strategy on individual level and population level on dental caries should put more attention on SSBs. Further experimental studies or research with advanced epidemiological instruments are needed for more confident recommendations on preventive strategies.
published_or_final_version
Public Health
Master
Master of Public Health

Negli ultimi anni le molecole bioattive con attività antimicrobica come tossine killer, batteriocine e agenti antifungini sono state impiegate per ridurre o inibire la crescita e lo sviluppo di funghi, lieviti e batteri indesiderati in alternativa o in combinazione con i composti sintetici antimicrobici negli alimenti e nelle bevande fermentate. La presente ricerca riguarda il ruolo e la caratterizzazione di molecole bioattive prodotte da lieviti appartenenti alle specie Metschnikowia pulcherrima, Tetrapisispora phaffii, Kluyveromyces wickerhamii, Wickerhamomyces anomalus. Dopo la caratterizzazione dei composti bioattivi prodotti da questi lieviti e lo studio dell'interazione tra le molecole antimicrobiche naturali e i lieviti/ le muffe sensibili, abbiamo voluto valutare il loro possibile impiego per combattere microrganismi contaminanti nell’agricoltura biologica e nel settore vinicolo. Nella prima parte della tesi è stata valutata l’azione inibente di sette ceppi di M. pulcherrima nei confronti di lieviti enologici principalmente coinvolti nel processo di vinificazione come Pichia, Candida, Hanseniaspora, Kluyveromyces, Saccharomycodes, Torulaspora, Brettanomyces e Saccharomyces. Un’efficace azione antagonista dei ceppi di M. pulcherrima è stata osservata nei confronti di lieviti indesiderati appartenenti ai generi Pichia, Brettanomyces e Hanseniaspora, mentre tale attività antimicrobica non si evidenziava nei confronti di Saccharomyces cerevisiae. Il secondo argomento trattato ha riguardato l’isolamento del gene che codifica Kpkt, la tossina killer prodotta da Tetrapisispora phaffii che possiede un’ampia attività antimicrobica nei confronti di vari lieviti alterativi del vino. La distruzione del gene ha provocato una perdita completa del fenotipo killer confermando così che TpBgl2p esercita un'attività antimicrobica. Il risultato ottenuto è la base per valutare la possibilità di esplorare la produzione eterologa della proteina che potrebbe essere utilizzata in campo enologico per ridurre le contaminazioni nel vino in sostituzione della SO2. Nella terza parte della tesi, l’attenzione è stata focalizzata sul danno indotto dalle tossine Kwkt and Pikt, prodotte rispettivamente da Kluyveromyces wickerhamii e Wickerhamomyces anomalus, coinvolte nel biocontrollo dei lieviti spoilage Brettanomyces/ Dekkera in vinificazione. L’effetto delle micocine è stato comparato con quello dell’anidride solforosa, generalmente usata come composto sintetico antimicrobico negli alimenti e nelle bevande fermentate. I risultati hanno mostrato diversi meccanismi di controllo della crescita di B. bruxellensis tra le due tossine e tra le tossine killer e il biossido di zolfo, anche se l'attività antimicrobica di quest’ultimo è fortemente influenzata dal fattore pH. Nella quarta parte della tesi è stata valutata l'interazione tra diversi lieviti ad attività antimicrobica e alcuni funghi filamentosi che in genere colonizzano i frutti maturi. Preliminarmente è stato eseguito uno screening in piastra per valutare l’eventuale effetto inibente di 42 lieviti verso 5 muffe, che causano i principali danni in frutta e verdura durante il periodo di post-raccolta. In una seconda fase, dieci ceppi selezionati sono stati testati per la loro attività inibitoria efficace contro le muffe in test in vivo su uva, limoni, arance, fragole e ciliegie. I risultati indicano che, tra i ceppi saggiati la migliore e interessante attività antagonista nei confronti delle muffe testate, è stata mostrata da due ceppi appartenenti a Wickerhamomyces anomalus e Metschnikowia pulcherrima.
In recent years, the bioactive compounds with antimicrobial activity such as yeast killer toxins, bacteriocins and natural antifungal agents are employed to reduce or inhibit the growth and the development of undesired fungi, yeasts or bacteria. Their use was proposed in alternative or in combination to the addition of synthetic antimicrobial agent in food and fermented beverage. The present research focused on the antimicrobial role and the characterization of bioactive molecules produced by yeast strains belonging to Metschnikowia pulcherrima, Tetrapisispora phaffii, Kluyveromyces wickerhamii, Wickerhamomyces anomalus species. Following a characterization of the antimicrobial compounds produced by these yeasts and investigating on the interaction between natural antimicrobial molecules and sensitive yeasts/moulds, the present study focused the attention on their use to combat contaminating microorganisms in “organic” agriculture and in wine industry. In the first part of the present thesis seven different strains of M. pulcherrima were screened to evaluate the growth inhibition of the main oenological yeasts such as Pichia, Candida, Hanseniaspora, Kluyveromyces, Saccharomycodes, Torulaspora, Brettanomyces and Saccharomyces involved in winemaking process. The effective antagonistic actions of M. pulcherrima strains was showed on undesired wild spoilage yeasts, such as the Pichia, Brettanomyces and Hanseniaspora genera, while Saccharomyces cerevisiae was not affected by the antimicrobial action of M. pulcherrima. The objective of the second part of this study was the isolation of the gene encoding Kpkt, a killer toxin produced by Tetrapisispora phaffii. The gene disruption caused a complete loss of the killer phenotype thus confirming that TpBgl2p exerts an effective killer activity and that the gene is effectively involved in the expression of the zymocin. The result obtained gives the basis to explore the heterologous production of the protein that could be used as starter in enological field to reduce wine contamination. In the third part of the thesis, the attention was focused on the damage induced by Kwkt and Pikt killer proteins, produced by Kluyveromyces wickerhamii and Wickerhamomyces anomalus, involved in the biocontrol of Brettanomyces/ Dekkera spoilage yeast in the wine industry. The effect of mycocins was also compared with sulfur dioxide, generally used as antiseptic in food and beverage industries. The results showed different mechanisms of control of B. bruxellensis growth within the two mycocins. Different mechanisms of action were also found between killer toxins and sulfur dioxide that is strongly influenced by pH. In the fourth part of this work it was evaluated the interaction between several yeasts that exhibit antimicrobial activity and some filamentous fungi that generally colonize mature fruits. Preliminarily, a plate screening was performed to assess inhibitory effect of 42 yeasts against 5 moulds, main spoilage microorganisms in vegetables and fruits during postharvest. In a second step, ten selected strains were tested for their effective inhibitory activity against moulds in vivo assay on grapes, lemons, oranges, strawberries and cherries. Results indicated that the best antagonistic activity was exhibited by Wickerhamomyces anomalus and Metschnikowia pulcherrima species that produced a significant reduction of moulds.

Stable retorted whey protein beverages with 5% protein concentration were prepared. The effect of protein concentration, fat concentration and homogenization pressure on the heat stability and the stability of emulsions of sterilized whey protein beverages was determined. Beverages containing >1% protein formed aggregates during the heat treatment. Food grade additives were added to the beverages with >1% protein to determine if the heat stability could be improved. Lecithins and polyphosphates improved the heat stability while hydrocolloids decreased the heat stability. Lecithins improved the heat stability of emulsions better than polyphosphates but polyphosphates were more effective in beverages without fat. Lecithins modified by acetylation or hydrolysis provided more protection against heat denaturation of proteins than regular lecithin. Acetylated lecithin created the emulsions most stable against creaming. Improvement in the emulsion stability by the use of phospholipids was associated with a more negative charge at the interface of the fat droplets. The effect of polyphosphates on the heat stability was related to the chain length of the polyphosphates. Short chain polyphosphates (dp~4) were more effective than other polyphosphates. Polyphosphates probably improved the heat stability of the systems by changing the structure of water and this prevented aggregation of whey proteins. Hydrocolloids decreased heat stability most probably through thermodynamic incompatibility that locally increased the concentration of proteins and promoted aggregation during the heat treatment.The effect of homogenization pressure, concentration of acetylated lecithin, and the concentration of short chain polyphosphate on the storage stability of retorted whey protein beverages containing 5% protein and 3% fat was determined. The creaming index and particle size index changed over 28 d of storage and indicated creaming of the emulsions. The use of homogenization pressures of 55 and 90 MPa compared to 20 MPa reduced the magnitude of the change of the particle size index and creaming index during storage. Inclusion of polyphosphates reduced the storage stability of the emulsions. Optimization of parameters showed that emulsions formulated with 5% protein, 3% fat and 0.3% lecithin without polyphosphates and homogenized at 90 MPa had the best stability after 28 d of storage.

Thesis (MTech (Food Technology))--Cape Technikon, 2004
Probiotic foods are intended to supply selected viable microorganisms, for example Lactobacillus acidophilus and Bifidobacterium, to consumers. These organisms, when consumed at the daily intake of 108 , provide benefits beyond basic nutrition. Probiotic (AB) foods generally include fermented dairy products such as yoghurts and cheeses, targeted at the upmarket consumer. However, due to technical problems associated with the foods and the organism, viable Bifidobacterium rarely occur in AB foods. The principle aims of this study were to develop a suitable delivery system for Bifidobacterium to the consumer, and to supply these living organisms in the affordable traditional fermented African beverages, amasi and mahewu. This would provide the benefits of probiotics to the rural African consumer, where malnutrition and gastrointestinal diseases occur. The organism selected for this study was Bifidobacterium lactis DSM 10140, commonly associated with AB starter cultures for yoghurts. The delivery system selected was microencapsulation of B. lactis using a mixture of the generally recognised as safe (GRAS) edible gums, gellan and xanthan. Supply vehicles for the microcapsules to the consumer were amasi and mahewu. Prior to microencapsulation, rheological studies were undertaken to determine whether the gellan-xanthan gum mix would provide a suitable support matrix for microencapsulated B. lactis. This was done using a Paar Physica MGR 300 rotational rheometer with a cone plate 50-2 measuring system. Results indicated that the hydrated gellan-xanthan gum mix behaved as a non-Newtonian material, and the flow curve fitted well to the Herschel-Bulkley model. This demonstrated that the gel was a relatively viscous material with solid properties. The average yield stress of the gel was 1.515 Pa, indicating that the gel was stable, and at lower stresses would behave as a solid. The gel mix would be disrupted by shear stresses associated with mastication and peristalsis. The minimum viscosity of the gel was constant at temperatures between 46°C - 61°C. It was concluded from these data that the gel was suitable for microencapsulation and that microcapsules should only be included in soft foods, which do not require chewing. Temperatures associated with microencapsulation, at minimum gel viscosities, were not lethal to B. lactis. Bifidobacterium lactis cells were incubated under anaerobic conditions (4% H2, 10% CO2, and 86% N2) at 37°C overnight in 250 ml Tryptone-Yeast-Glucose (TYG) broth, and grown to an 00600 0.9 - 1.1. Cells were harvested and washed for microencapsulation using centrifugation. Microencapsulation of the organism was done using a mono-axial extrusion technique together with a superposed airflow, by manually extruding the aqueous gum I cell mix through a 27.5 G bevelled needle, fitted on to a 10 ml syringe. The resultant microdroplets were hardened by free fall into 0.1 M CaCI2 solution. Microcapsules were separated from the CaCI2 solution by filtration through Whatman No.1 filter paper. All procedures were carried out in a laminar flow hood. Results indicated that the method of microencapsulation used in this study was successful. Using a concentrated inoculum of B. lactis, high numbers (lOglO 11-12 etu.g-1 ) of bacteria were incorporated into the microcapsules. Therefore the daily intake would be provided by 0.1 g microcapsules. The diameter and size distribution of microcapsules were determined by laser diffractometry. This showed a maximum microcapsule diameter of 2.22 mm with 50% (w/v) of the microcapsules having a diameter of < 0.637 mm. Although this represents a considerable size variation, this would not adversely affect mouthfeel of the beverages, as only 0.1 g microcapsules would be required to obtain at least 108 B. lactis in any volume of amasi or mahewu. To enumerate immobilised viable B. lactis, two techniques were compared. These involved the use of either a pestle and mortar, or high power ultrasound (HPUS) (20 kHz, 750 W). Results showed that HPUS was superior to the pestle and mortar technique. A short exposure (15 s) to HPUS disrupted the matrix releasing all entrapped etus, whereas when using the pestle and mortar xiii technique, cells remained partially entrapped in the gel. Therefore the pestle and mortar technique yielded lower cfu values than expected. The survival of microencapsulated B. lactis, in 1 M sodium phosphate buffer, was studied as a possible means of supply of microcapsules to industry for incorporation into foods. Microcapsules were stored in the buffer for 21 days at either 4°C or 22°C. Results showed that cell viability was not significantly reduced (p>0.05) at either temperature after 21 days. Hence this form of storage could be used to deliver viable immobilised B. lactis to the food industry. In order to assess the survival of immobilised B. lactis in the GIT, the microcapsules were incubated at 37°C over a period of 240 min in simulated gastric juice (SGJ) (pH 1.5). Viable counts were performed by sampling at regular intervals. A similar study was done in simulated bile and pancreatic juices (BPJ) (pH 6.5). In SGJ, it was demonstrated that there was a significant reduction (3 log cycles) (p<0.05) of free cells after 240 min. However, this trend was not noted for microencapsulated B. lactis. Therefore, the gellanxanthan gel matrix protected B. lactis from the lethal effect of SGJ. In BPJ, no significant difference (p>0.05) was noted for surviving fractions of both immobilised and free B. lactis. Commercial pasteurised amasi (pH 4.4) and mahewu (pH 3.5) were selected as the supply vehicles for the microencapsulated B. lactis. Known numbers of viable microencapsulated and free B. lactis cells were added to both beverages. For most samples, incubation was at either 4°C or 22°C for 21 days in the presence of atmospheric oxygen. In addition, free cells were incubated anaerobically at 22°C. As oxygen is limiting in the microcapsules, these were not incubated under anaerobic conditions. The survival I shelf-life studies of commercial amasi indicated no significant difference (p>0.05) in survival rate between immobilised and free B. lactis cells. The reduction noted for viable counts of immobilised or free B. lactis cells was approximately 1.5 log cycles. Even so, after 21 days viable immobilised B. lactis (1010 0.1 g'l microcapsules) remained in excess of the daily intake 108 , whereas in the free B. lactis cells, the viable count declined to 106 mr1 . Statistical analyses showed that temperature or oxygen presence had little effect on the survival of both immobilised or free B. lactis cells (p>O.05). In mahewu, decline in viability of cells was observed for most samples. However microencapsulation enhanced cell survival at both 4°C and 22°C when compared to free cells. The decrease in viable B. lactis free cells occurred more rapidly (3 log cycles) in mahewu, than in amasi, at both 4°C and 22°C. Throughout the shelf-life studies it was apparent that viable B. lactis cell numbers did not increase. This was advantageous as metabolites associated with B. lactis growth would have adversely altered the taste of both amasi and mahewu. Sensory evaluation of the traditional fermented African beverages, enriched with either viable immobilised or free B. lactis, was done in order to determine consumer response to the product. An analytically trained 12-member taste panel analysed the beverages for colour, texture, and taste. The triangle taste test procedure was used. No differences were detected with regard to texture, and colour of the fermented beverages containing immobilised B. lactis. However, in the fermented beverages containing free cells, a change in viscosity was noted. There was a significant difference (p