Academic literature on the topic 'Yellow alkaline noodles'

Composite samples of Canada Western Red Winter wheat (CWRW) with varying levels of Fusarium head blight damage (0.5–9.6%) were prepared from the 1998 Western Canadian harvest survey and milled to yield both patent (60% extraction) and straight grade (~76%) flours. The mycotoxin deoxynivalenol (DON) levels in the flours ranged from 0.21 to 2.6 ppm with no significant influence due to flour extraction. No differences were attributable to Fusarium damage (FD) in the amount of work required to sheet either yellow alkaline (YA) or white salted (WS) noodles. The color of the raw (YA) noodles was adversely affected by FD as a significant loss in noodle brightness (L*) and an increase in redness (a*) were observed for noodles prepared from both patent and straight grade flour. Straight grade YA noodles, prepared from wheat with FD levels above acceptable limits for milling grades, displayed a significant loss in yellowness (b*) after aging for 24 h. Differences in noodle brightness of raw WS noodles were observed between the control and 9.6% FD samples for both patent and straight grade noodles at 24 h. Analysis of YA and WS noodles indicated a significant linear relationship between the number of specks and the quantity of FD in the wheat. YA and WS noodles displayed significant loss in cooked noodle texture with increasing FD levels. Maximum cutting stress and recovery declined with increasing FD for both noodle types whether made from patent or straight grade flour. Maximum wheat FD tolerances below 2% are required in order to ensure optimum noodle quality. Key words: Fusarium damage, noodles, color, texture and image analysis

Instant noodles originated in eastern nations and have been accepted due to its practicality and low cost. However, its high sodium content can lead to health problems. The present study aimed to reduce sodium and increase calcium levels in noodles. A control (N1: K2CO3+ Na2CO3) and three treatments with the addition of calcium carbonate in combination with alkaline salts such as potassium and sodium carbonates (N2: K2CO3+ CaCO3; N3: Na2CO3+ CaCO3; and N4: CaCO3) were studied. Two hydration methods were investigated, and the technological characterization and the calcium bioaccessibility of the different noodle formulations were determined. N4 did not fit into the alkaline noodle category due to its neutral pH. N2 and N4 showed a sodium reduction of around 28% and a significant increase in calcium content, with higher bioaccessible calcium. Significant changes were observed for the noodles made with the addition of different alkaline salts, with a light-yellow color and better texture than the control, which can be a positive aspect, once products with reduced nutrients usually present differentiated coloring. Therefore, the use of calcium carbonate may be a promising alternative to increase Ca intake and to reduce the sodium content of instant noodles.

The colour of Asian yellow alkaline noodles is an important indicator of quality and influences consumer choice. Apigenin di-C-glycosides (ACGs) and lutein present in wheat flour have been reported to contribute to the yellow colour; however, their relative roles have not been quantified. This study was conducted to quantify the contribution of ACGs to the part of the yellow colour that develops in the presence of alkaline salts and to assess the potential for improving colour. Whereas lutein is present in all grain tissues, ACGs are concentrated in the embryo. Significant genetic variation was apparent for ACG content, but there was no significant correlation between grain content and the amount recovered in milled flour. The yellow colour caused by the reaction of flour constituents with alkali was estimated to be ~5–6 b* units or ~22–27% of total yellow colour. However, only 1–2 units (5–10% of total yellow colour) could be attributed to ACGs, suggesting that a significant portion of the yellow colour of alkaline noodles is due to other unidentified factors or compounds.

Diep, S., Daugelaite, D., Strybulevych, A., Scanlon, M., Page, J. and Hatcher, D. 2014. Use of ultrasound to discern differences in Asian noodles prepared across wheat classes and between varieties. Can. J. Plant Sci. 94: 525–534. Nine wheat varieties, five Canada Western Red Spring (CWRS) and four Canada Prairie Spring Red (CPSR), grown at the same locations and composited by variety, were milled to yield 65% extraction flours, which were used to form yellow alkaline raw and cooked noodles. The CWRS flours were ∼2% higher in protein content than the CPSR varieties, with varieties within each class exhibiting a wide range in dough strength as determined by Farinograph dough development time and stability. The ultrasonic velocity and attenuation of the raw noodles were measured at 40 kHz in disk-shaped samples, enabling the longitudinal storage modulus, loss modulus and tan Δ to be determined. Significant differences (P=0.05) between classes and within a class were found to exist for all ultrasonic parameters. In general, the CPSR varieties generated the highest storage moduli values, the lowest loss moduli, and the lowest tan Δ values, indicating this class/varieties exhibited a more elastic (firmer) raw noodle than the CWRS varieties even at a 2% lower protein content. A significant correlation, r=0.72,0.70, P=0.03, was also found between raw noodle velocity and M”, respectively, with cooked noodle bite as determined by maximum cutting stress.

Wheat and wheat products represent a major food staple consumed around the world. Asian noodles account for the end-use of at least twelve percent of all wheat produced globally. Whereas there has been extensive research into the role and significance of enzymes in the utilisation of wheat flour in bread-making, less is known of their role in Asian noodles. Accordingly, this study has been based on the hypothesis that some enzymes will have a significant impact on the quality characteristics of at least some styles of Asian noodle products. Five enzymes were selected for study: á-amylase, lipase, lipoxygenase, peroxidase and ascorbic acid oxidase. The focus has been on the processing of white salted and yellow alkaline styles of Asian noodles and the role of the enzymes in relation to the quality attributes of these products has been systematically investigated. The quality aspects encompass colour and colour stability, texture, cooking properties as well as structural characteristics of the products. As a part of the preliminary phases of the investigation, procedures for analysis and assessment of flours and noodles have been evaluated. In particular, for the textural properties of noodles, results were obtained with the TA-XT2 Texture Analyser using both a flat cylinder probe, to measure noodle hardness, and also a cutting blade measuring noodle firmness. In addition, various approaches were trialled for sample preparation and presentation in the use of scanning electron microscopy for the investigation of noodle structure. In order to measure the activity of the enzymes in flours and noodle products, assay procedures were set up and validated. These were then used for the analysis of a series of commercial flours and the levels of activity in each of the flours was relatively low indicating that they had been milled from wheat which had not been subjected to preharvest sprouting. á-Amylase was measured using the Ceralpha method and two different sources of exogenous á-amylase (bacterial and barley) were added to noodle formulations. In preliminary experiments various levels of á-amylase incorporation were compared and Abstract viii the impact on texture measured. Both sources of á-amylase resulted in softer noodle products. Adverse effects of the preparations on colour were observed in fresh noodles, although the differences were less obvious when noodles were cooked or dried immediately after preparation. Cooking losses were higher in noodles incorporating amylase, particularly the bacterial preparation. These impacts were reflected in changes in the appearance of starch granules in scanning electron micrographs of the noodles. Three different lipase preparations were studied and their incorporation had only minor effects on texture of noodles. Addition of wheat germ lipase resulted in slightly softer noodles, fungal lipase caused slightly harder noodles, while addition of porcine pancreas lipase gave harder noodles in the raw state and softer noodles after cooking. Similarly variable results were observed when colour and colour stability were evaluated, and there were no adverse effects upon cooking quality of Asian noodles. Two different preparations of horseradish peroxidase were investigated and both resulted in adverse effects on colour including at all stages of storage. One of the preparations resulted in softer noodles when texture was measured using the cylinder method and in firmer noodles when the blade attachment was applied. Neither the surface appearance of noodles nor the cooking properties were altered by the addition of peroxidase to the formulations. Different levels of addition of ascorbic acid oxidase from Cucurbita species showed only minor effects on characteristics for both styles of noodles. Incorporation of this enzyme resulted in lower lightness values but there was little effect on yellowness. Discolouration of noodle sheets was faster and more obvious at 25°C and compared to the storage of noodles at 4°C. The cooking qualities of noodles did not change upon addition of the oxidase. Activity of the enzyme lipoxygenase was measured spectrophotometrically using linoleic acid as substrate. Upon addition to the noodle formulations the enzyme preparation from soy bean resulted in slightly harder and firmer noodles. Colour and colour stability were not enhanced by the addition of lipoxygenase and significantly higher yellowness values were measured in some samples. This enzyme did not adversely impact upon the cooking or structural properties of either style of noodles. Abstract ix Some of the enzymes studied here demonstrated undesirable impacts on one or another aspect of noodle quality, particularly producing darkening or soft textural characteristics. Enzymes that might usefully be considered at lower levels of addition are ascorbic acid oxidase, porcine pancreas lipase and lipoxygenase. These three had no negative effects upon texture, structure or cooking quality of noodles. Visually the colour properties were not adversely impacted and instrumental assessment indicated brighter noodle sheet colours. At lower levels of addition, these three enzymes provide enhancement of noodle quality. On the other hand peroxidase, the two amylases and lipases affected the colour and colour stability of noodles. It was observed that the amylase preparations did result in pronounced softening of noodles. However, the data indicate that the adverse impact attributed to this enzyme when flour from sprouted wheat is used in noodle processing, are probably due to enzyme activities other than a- amylase.

Doctor of Philosophy
Polyphenol oxidase (PPO) catalyses undesirable darkening in wheat products such as Asian noodles. Genetic variation for PPO activity is characterized in bread wheat. Australian wheat breeding programmes recognize that reduced PPO activity is an important quality target. Despite this interest from breeders, no varieties possessing extremely low and null PPO activity exist. The development of null PPO wheat varieties is dependant on an understanding of the genetic control of the null phenotype. Knowledge of these factors will accelerate efforts to develop them. The inheritance of PPO activity was investigated in two populations that were derived from hybrids between a null PPO genotype and Australian wheat varieties Lang and QAlBis. Observed genetic ratios were consistent with two and three gene control, respectively in these populations. QTL mapping was performed in the QALBis x VAW08-A17 population. The Diversity Array Technology (DArT) approach was employed to genotype the QALBis x VAW08-A17 population. Three highly significant QTLs that control PPO activity were identified on chromosomes 2AL, 2BS and 2DL. Close associations between PPO activity and DArT marker loci wPt-7024, wPt-0094 and wPt-2544 were observed, respectively. Collectively, these loci explained 74% of the observed variation in PPO activity across seasons. Significant QTLs on chromosomes 1B and 3B were also identified that together explained an additional 17% of variation in PPO activity. The relationship between PPO activity and yellow alkaline noodles (YAN) colour stability parameters was investigated in a DM5637*B8 x H45 doubled haploid population. PPO activity and changes in YAN brightness (ΔL* 0-24h) and yellowness (Δb* 0-24h) in both seasons were analysed. Quantitative trait analyses of PPO activity, flour yellowness (b*) and YAN colour stability was also conducted in this population. QTL mapping of variation in PPO activity in the DM5637*B8 x H45 DH population identified a highly significant QTL on chromosome 2AL, which explained 52% of the observed variation across seasons. Regression analysis identified that wPt-7024 was highly significantly associated with PPO activity in this population. A highly significant association between this marker and PPO was also identified in the QALBis x VAW08-A17 population. Collectively, the three identified QTLs (on chromosomes 2AL, 7A and 7B) explained 71% of variation in PPO activity across seasons. A highly significant (P<0.001) QTL on chromosome 2B along with significant (P<0.01) QTLs on the chromosomes 1A, 3B, 4B and 5B were found to control flour yellowness. The QTLs on 2B, 4B and 5B were detected in both seasons analysed and accounted for 90% of variation in flour b* across seasons. The study on YAN colour stability located two highly significant (P<0.001) QTLs and two significant (P<0.01) QTLs that controlled the change in brightness of yellow alkaline noodle. The 2A QTL accounted for 64% of observed variation across seasons. It was in the same location as the PPO QTL and shared a common closest marker wPt-7024. Only one significant QTL for YAN a* (0-24h) was identified. It accounted for 12% of variation across seasons and was only detected in one season. One highly significant (P<0.001) QTL and two significant (P<0.01) QTLs were identified that controlled the change in yellowness of yellow alkaline noodle. The 2A QTL accounted for 68% of observed variation across seasons. The location of this QTL corresponded with that of 2A QTLs for PPO activity and L* of YAN in this study. Furthermore, wPt-7024 was also identified as the marker with the most significant association with L*. The identification of a correlation between the characters and a common location of a highly significant QTL for each of these characters indicates that it is likely that PPO activity is directly responsible for a large proportion of the changes in brightness and yellowness of YAN. QTLs for L* and b* of YAN were detected in a common location on chromosome 1A. However, no corresponding QTL was identified that controls PPO activity, highlighting the complexity of the relationship between these traits. Resistance to three rust pathogens (Puccinia graminis, Puccinia striiformis, and Puccinia triticina) was also investigated in the DM5637*B8 x H45 DH population because they are major yield limiting diseases in wheat. Disease response data at the seedling stage were converted to genotypic scores for rust genes Sr24/Lr24, Sr36, Lr13 and Yr7 to construct a genetic linkage map. No recombination was observed between rust resistance genes Sr36, Lr13 and Yr7 in this DH population. Therefore, these genes mapped in the same position on chromosome 2B. The Lr24/Sr24 locus was incorporated into the chromosome 3D map. Interval mapping analysis identified QTLs on chromosomes 2B, 3B, 4B and 5B that control adult plant resistance (APR) to stripe rust. Two QTLs on chromosomes 2B and 3D were identified that controlled APR to leaf rust in this DH population.

Colour is an important determinant of quality and customer appeal for Asian noodles that are made from bread wheat (Triticum aestivum L.). The Asian noodle market represents approximately one third of wheat exports from Australia and as a consequence maintaining and improving colour for noodles is an important research and breeding objective. The focus of this project is yellow alkaline noodles (YAN) prepared using wheat flour and alkaline salts, sodium and potassium carbonate, and for which a bright yellow colour is desired. Xanthophylls, primarily lutein, and apigenin di-Cglycosides (ACGs) have been shown to be important components of this yellow colour. ACGs were of particular interest since, in contrast to lutein, the content in flour could be increased without adverse effects on colour of other end-products. There was little information either on the genetic variation for ACG content or the mechanism and genetic control of biosynthesis which was surprising in view of their putative role in a wide range of plant processes, food colour and flavour, and possibly human health. The aims of this project were to provide new information on the role of ACGs in YAN colour and genetic regulation of their biosynthesis. To achieve this aims: genetic variation in grain ACG traits in bread wheat and related species was surveyed, the quantitative contribution of ACG to the yellow colour of YAN was determined and compared to lutein, QTL for ACG content and composition were located, and candidate genes associated with variation in ACG composition identified. Substantial variation in both grain ACG content and the ratio, ACG1/ACG2, were identified within bread wheat cultivars and related species. Genotype controlled the major portion of the variation. ACG content appeared to be a multigenic trait whereas variation in ACG1/ACG2 was associated with a limited number of chromosomes, in particular chromosomes 1B, 7B and 7D. In the absence of chromosome 7B (Chinese Spring 7B nullisomics) there was a substantial increase in ACG1/ACG2, i.e. a relative increase in the glucose-containing isomer, possibly indicating the presence of a Cglycosyltransferase on 7B with specificity for UDP-galactose. A similar phenotype observed in some wheat cultivars could be explained by a deletion or mutation of a gene controlling this enzyme. The results suggest that it should be possible to manipulate both ACG content and composition through breeding. Only 30% of ACG (means 19.3 µg/g) is recovered in flour, which contributed to 1 to 3 CIE b* units to the part of the yellow colour of yellow alkaline noodles (YAN) that develops specifically in the presence of alkali. The relatively low recovery of ACG in flour contrasts with the high recovery of lutein (90%, with means 1.011 µg/g). Since the difference between white salted noodles (WSN) and YAN is approximately 6 b* units, this would indicate that another unidentified compound(s) is responsible for the difference. Potential for ACG0-based improvement of bread wheat cultivars for YAN yellowness is likely to be limited by the range of genetic variation, the location of ACG in grain tissues that are largely discarded during milling and the lack of correlation between grain and flour ACG content. Moreover, the observed variation in ACG recovery in small scale milling was not reflected in larger scale milling anticipated to better represent commercial practice. The improvement in flour recovery and the amount of ACG recovered in the flour were not significant and not enough to achieve the yellowness of commercial noodles. Selection that requires larger scale milling is costly, time consuming and not applicable to early generation screening. In this context, further work on QTL associated with variation in ACG content and development of marker-assisted-selection would be very useful. Addition of thirteen new markers to the QTL region for ACG trait on chromosome 7BS in a Sunco/Tasman doubled haploid population reduced the size of the QTL interval from 28.8cM to approximately 5.5cM. In this revised 7BS map, the major QTL for ACG1 and ACG2 content as well as ACG1/ACG2 ratio were detected within 4.7cM of SSR marker Xwmc76. The QTL region linked to Xwmc76 was shown to be syntenic with a region in rice chromosome 6S between AP005387 and AP005761 and a region on Brachypodium chromosome 1. Based on these comparisons, the most likely candidate gene associated with variation in ACG composition appeared to be a glycosyltransferase. Alternate alleles at the 7BS QTL may be associated with amino acid changes within the C glycosyltransferase that shift the substrate specificity from galactose (ACG2, Tasman) to glucose (ACG1, Sunco). Alternatively, based on a comparison of Chinese Spring nullisomic-tetrasomic lines where nullisomic 7B was associated with a phenotype similar to Sunco, it is possible that Sunco contains a null allele. Other candidate genes located on the same chromosome that could potentially be involved in ACG biosynthesis were identified and included a sugar transporter, which could determine the relative sizes of the available pools of UDP-glucose and UDPgalactose, an epimerase required for inter-conversion of these sugars, other glycosyltransferases and a flavone-2-hydroxylase (F2H) involved in the first committed step in the pathway to ACG. Research approaches that could be used to validate the role of the candidate gene are discussed along with other options for improving the colour of wheat cultivars for the YAN market. Options for utilizing ACG as yellow pigment of noodles might include incorporating the embryo or seed coat materials (pollard and bran) into the flour after milling and genetic modification of bread wheat to achieve ACG expression in the starchy endosperm.
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2012