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In the context of valorizing underutilized crops, this study investigated the starch and protein characteristics of chestnut varieties (Balestrera and Rossera) and their potential for use at 15% and 25% in reformulating gluten-free baked snacks and fresh pasta. Chestnut varieties differ in protein and starch content (Balestrera > Rossera), as well as in amylose, dietary fiber, and lipids (Balestrera < Rossera). Differences in starch and amylose content affected starch gelatinization (Balestrera < Rossera), pasting and retrogradation properties, and water absorption capacity at 90 °C (Balestrera > Rossera). No differences in water and oil absorption capacity and mixing properties were observed, neither in the protein profile nor in the nature of protein aggregates. Both varieties exhibited a good aptitude for producing gluten-free baked snacks and fresh pasta, even at enrichment levels of 25%. Overall, this study could provide valuable information for the development of gluten-free products using sustainable, underutilized crops.

Genes play a pivotal role in regulating the germination of cereal grains; however, there is limited research on the impact of germination genes on the physicochemical properties of germinated cereal starch. We investigated the effects of the OsGA20ox1 gene on the multiscale structural features and adhesion behavior of germinated brown rice starch. Compared to the knockout lines group, the wild type exhibited a decrease in double-helix content (62.74 %), relative crystallinity (47.39 %), and short-range molecular ordering (2.47 %), accompanied by enhanced erosion on the surface of starch granules. The damage to glycosidic bonds at the double-helix level and the heightened structural amorphization (90.95 %) led to reduced entanglement and interaction among starch molecules, ultimately resulting in reduced characteristic viscosity. Further transcriptomic analysis revealed that OsGA20ox1 could regulate the expression of starch-related enzyme genes in the starch metabolism pathway during germination of brown rice. This study contributes to understanding the role of germination genes in promoting the physicochemical properties of starch in germinated grains, thereby opening up new avenues for the improvement of plant-based starch, and paving the way for further research in this field., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

The objective of this work was to study the effects of heat-moisture treatment (HMT) of freshly harvested mature high-amylose maize (HAM) kernels on its starch structure, properties, and digestibility. Freshly harvested HAM kernels were sealed in Pyrex glass bottles and treated at 80 °C, 100 °C, or 120 °C. HMT of HAM kernels had no impact on its starch X-ray diffraction pattern but increased the relative crystallinity. This result together with the increased starch gelatinization temperatures and enthalpy change indicated starch molecules reorganization forming long-chain double-helical crystalline structure during HMT of HAM kernels. The aggregation of starch granules were observed after HMT, indicating interaction of starch granules and other components. This interaction and the high-temperature crystalline structure led to reductions in the starch digestibility, swelling power, solubility, and pasting viscosity of the HAM flours. Some starch granules remained intact and showed strong birefringence after the HAM flours were precooked at 100 °C for 20 min and followed by enzymatic hydrolysis, and the amount of undigested starch granules increased with increasing HMT temperatures. This result further supported that HMT of HAM kernels with high moisture level could increase the starch thermal stability and enzymatic resistance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Bananas and plantains are important food sources for many people in the world. Their high starch content places them among the highest energy providers. This study aimed to determine the effects of altitude on banana starch properties in Cameroon. A dessert banana, a cooking banana, a plantain cultivar, and a plantain-like hybrid were grown at low and high altitudes (respectively at 80 m and 1300 m above sea level)., Results: Starch analyses showed an increase in moisture and pH values against a drop in total titratable acidity and dry matter content with respect to altitude. Amylose content, as well as water absorption capacity, oil absorption capacity and syneresis of high-altitude plantain and plantain-like hybrid, were significantly higher. Starch digestibility was low and ranged between 13.4% and 37.9% after 2 h of incubation. High-altitude plantain starches contained more amylose and were more resistant to enzymatic hydrolysis., Conclusion: Starches from CARBAP K74 and Kelong mekintu, grown at high altitude, showed good water and oil absorption capacities, low digestibility, and high resistance. The adequate properties of these banana starches predispose them for use as thickeners and gelling agents as well as ingredients for the formulation of low-calorie foods. This study highlights the importance of altitude when discussing banana and plantain starch properties. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Pulsed electric field (PEF) technology was used to extract starch from Q. robur flours using low-intensity electric fields (0 and 0.1 kV/cm) and study the impact of PEF on the structure and properties of acorn starch concerning commercial starch. PEF technology is an advantageous method for starch extraction than the aqueous steeping from an industrial perspective since reduces extraction time and allows for continuous processing of larger suspension volumes. PEF technology preserved the amylose and amylopectin contents, hydrogen bonds, and diffraction patterns, as well as the starch native properties. Hence, PEF could be used to obtain native starches, but future studies should verify its economic viability. Acorn starches have lower damaged starch content, gelatinization temperatures, enthalpies, improved pseudoplastic behavior, reduced in-vitro digestibility, and lower resistance to deformation compared to commercial corn starch. The higher solubility and swelling power of acorn starches up to 80 °C make them a suitable food additive in fermented yogurt and milk products and thus help to value acorn and acorn starches. Hence, acorns can be used to obtain native starches, a food ingredient with a wide range of food and non-food usage, using PEF., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The difference in grain yield between superior grains (SG) on the upper part and inferior grains (IG) on the lower part of the same panicle was widely reported. To date, variations in rice taste quality between SG and IG and the related starch physicochemical properties remained poorly understood. Here, rice cultivars with different taste quality (NT, normal taste; GT, good taste) were grown to investigate the mechanism underlying taste difference between SG and IG and the correlation between cooked rice taste and starch properties. In this study, the taste value of GT rice was 32.2% higher than that of NT rice across the cultivars. The GT rice comprised a series of typical taste qualities of larger stickiness, smaller hardness, lower apparent amylose content (AAC), and lower protein content (PC). The taste quality differed among rice grains on the same panicle; SG achieved 21.9% and 17.0% higher taste value than IG in GT rice and NT rice, respectively. The higher taste value in SG was owing to the larger stickiness and lower PC. Meanwhile, SG of GT rice achieved the lowest PC (8.2%) and gluten content (5.6%), which might indicate a better health value. Additionally, larger and smoother granules, more fa (DP < 12), lower crystallinity, and larger 1045/1022 cm -1 ratios were found in SG starch compared to IG starch. These led to a weaker swelling power and lower gelatinization enthalpy in SG starch, while gelatinization temperature and retrogression enthalpy were the opposite. Moreover, SG starch exhibited higher storage modulus, loss modulus, slowly digestible starch contents, and resistant starch contents than IG. Our results revealed a great difference in taste quality between SG and IG in rice. The larger and smoother starch granules and shorter chain length could increase the ordered structure of starch, thus improving swelling power, gelatinization properties, and rheological characteristics and facilitating better taste quality of SG over IG. Besides, the lower PC (especially gluten content), higher slowly digestible starch, and higher resistant starch content indicated a more promising health value of SG in the food industry., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

As a non-thermal processing method, the ultrasound treatment prior to the frying process has been demonstrated with great potential in reducing the oil absorption of fried food. This research aimed to evaluate the effect of ultrasound pretreatment on starch properties, water status, pore characteristics, and the oil absorption of potato slices. Ultrasound probe set with two power (360 W and 600 W) at the frequency of 20 kHz for 60 min was applied to perform the pretreatments. The results showed that ultrasound pretreatment led to the surface erosion of starch granules and higher power made the structure of starch disorganized. Moreover, the fraction of bound water and immobilized water were changed after ultrasonic pretreatment. Pores with the minor diameters (0.4-3 μm and 7-12 μm) were formed after ultrasound pretreatment. The penetrated surface oil (PSO) content, and structure oil (STO) content were reduced by 27.31% and 22.25% respectively with lower power ultrasound pretreatment. As the ultrasound power increased, the surface oil (SO) content and PSO content increased by 25.34% and 12.89% respectively, while STO content decreased by 38.05%. By using ultrasonic prior to frying, the quality of potato chips has been greatly improved., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Phosphate fertilisation affects the growth, development and quality of Tartary buckwheat. In this study, the effect of different phosphorus levels, including 0, 15, 75, and 135 kg/ha (non-, low-, medium-, and high-phosphorus levels, respectively), on the characteristics of starch from Tartary buckwheat were investigated in 2015 and 2017. With increased phosphorus level, the median diameter of starch granules and the apparent amylose content initially decreased and then increased. All starch samples showed the features of A-type X-ray diffraction patterns. Starches under medium-phosphorus treatment showed higher relative crystallinity than those under non-phosphorus treatment, as well as the highest solubility, gelatinisation enthalpy and transmittance among all starches. Starches under low-phosphorus treatment exhibited higher pasting properties than those under non-phosphorus treatment. This research revealed that phosphorus treatments and year significantly affected the physicochemical properties of Tartary buckwheat starch, and can provide information for the applications of starch in the food and non-food industries., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The starch market is very diverse and demanding regarding the functional characteristics of the product. However, no technique based on the management of cassava root harvest time has been applied to obtain starches with different properties. Thus, in this study, cassava roots were harvested at different times and the structure and physicochemical properties of their starches were analyzed. Results indicated the time points in the first growth cycle of plants when all parameters associated with root growth were at their highest values. It was also observed that changes in the time of harvest leads to the production of starches with different granule size, crystallinity, and content of amylose and phosphorus, which resulted in changes in the thermal and pasting properties, as well as in the solubility of the starches and swelling power; that is, on the main determinant characteristics for applicability of the starches. Planned agricultural production monitoring, coupled with the analysis of the main starches characteristics for large-scale cassava crops, can provide commercial benefits for both farmers and industry, as it is possible to obtain starches with desired physicochemical characteristics for varied applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nitrogen is an essential nutrient for Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) because this substance affects the yield and quality of Tartary buckwheat. The physicochemical characteristics of starch represent the important parameters of Tartary buckwheat quality. The effects of different levels of nitrogen application at different levels (0, 45, 135 and 225kg/ha in 2015 and 0, 90, 180 and 270kg/ha in 2017) on the physicochemical characteristics of Tartary buckwheat starch were studied. The amylose content, particle size and retrogradation of Tartary buckwheat starch with nitrogen were lower than those of without nitrogen. The structure complexity, pasting temperature, gelatinization enthalpy, relative crystallinity, light transmittance and solubility of the former were higher than those of the latter. Nitrogen application did not change the 'A'-type crystalline pattern of Tartary buckwheat starch. This study indicated that nitrogen level and years and the interactions among nitrogen fertilizer levels and years significantly affected the physicochemical properties of Tartary buckwheat starch. These integrated results also provided information about the management of fertilization conditions to obtain starches with special properties for applications in food or nonfood industries., (Copyright © 2019. Published by Elsevier B.V.)

Potato starch serves as an excellent raw material or food additive in the food industry. With the advancement of the potato staple food strategy in China, improving the potato starch yield and quality has attracted more and more attention. Potassium is an essential nutrient for potato due to its direct effects on the yield and quality of potato tubers. Here, the effects of three different potassium levels on potato starch physicochemical properties were evaluated by field experiments. With increasing potassium fertilization rates, the amylose content, phosphorus content and particle size decreased, thereby resulting in low gelatinization temperature, breakdown and setback viscosity, and high swelling power, relative crystallinity and transparency. Our study indicated that enhanced potassium fertilization improved the resistance to heat and shear stress and decreased the retrogradation of starch, and the 270 kg/ha potassium fertilization rate could obtain the highest tuber and starch production with desirable starch physicochemical properties. The integrated results also provide some novel insights into the management of the fertilization conditions to obtain native starches with special properties., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Starch was isolated from the kernels of jackfruit, longan, loquat, litchi, and mango fruits, which contained approximately 56, 59, 71, 53, and 64% starch, respectively, indicating that these fruit kernels are good starch sources. The structural and functional properties of these isolated starches were investigated and compared. The starches had irregular, truncated, spherical, and elliptical shapes with central hila and exhibited different sizes, with mango starch being the largest and jackfruit and longan starches being the smallest. The five starches had similar amylose contents but exhibited significantly different crystalline properties including crystalline type, relative crystallinity, short-range ordered structure, and lamellar intensity. Among the five starches, the jackfruit and loquat starches had the highest and lowest gelatinization temperature and enthalpy, respectively, and the litchi and mango starches had the highest and lowest pasting viscosity, respectively. The longan and loquat starches were more susceptible to enzyme hydrolysis than the other starches., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Protein phosphorylation plays important roles in regulation of various molecular events such as plant growth and seed development. However, its involvement in starch biosynthesis is less understood. Here, a comparative phosphoproteomic analysis of two indica rice cultivars during grain development was performed. A total of 2079 and 2434 phosphopeptides from 1273 and 1442 phosphoproteins were identified, covering 2441 and 2808 phosphosites in indica rice 9311 and Guangluai4 (GLA4), respectively. Comparative analysis identified 303 differentially phosphorylated peptides, and 120 and 258 specifically phosphorylated peptides in 9311 and GLA4, respectively. Phosphopeptides in starch biosynthesis related enzymes such as AGPase, SSIIa, SSIIIa, BEI, BEIIb, PUL, and Pho1were identified. GLA4 and 9311 had different amylose content, pasting viscosities, and gelatinization temperature, suggesting subtle difference in starch biosynthesis and regulation between GLA4 and 9311. Our study will give added impetus to further understanding the regulatory mechanism of starch biosynthesis at the phosphorylation level.

Fruit wastes constituting up to half of total fruit weight represent a large pool of untapped resources for isolation of starch with diverse applications. In this work, the possibility of isolating starch from tropical fruit wastes and its extended application as a natural coagulant was elucidated. Amongst the 12 various parts of fruit wastes selected, only jackfruit seeds contained more than 50% of total starch content. Using alkaline extraction procedures, starch has been successfully isolated from local jackfruit seeds with a yield of approximately 18%. Bell-shaped starch granules were observed under SEM with a granule size ranging from 1.1 to 41.6 μm. Detailed starch characteristics were performed to provide a comparison between the isolated seed starch and also conventional starches. Among them, chemical properties such as the content of starch, amylose, amylopectin and the corresponding molecular weights are some of the key characteristics which governed their performance as natural coagulants. The potential use of isolated seed starch as an aid was then demonstrated in both suspensions of kaolin (model synthetic system) and Chlorella sp. microalga (real-time application) with plausible outcomes. At optimized starch dosage of 60 mg/L, the overall turbidity removal in kaolin was enhanced by at least 25% at a fixed alum dosage of 2.1 mg/L. Positive turbidity and COD removals were also observed in the treatment of Chlorella suspensions. Starches which served as bridging agents aided in the linkage of neighbouring microflocs and subsequently, forming macroflocs through a secondary coagulation mechanism: adsorption and bridging.

The objective of this study was to understand dosage effects of the Waxy gene on the structures of amylose and amylopectin and on the properties of corn starch. Reciprocal crossing of isogenic normal and waxy corn lines was conducted to develop hybrids with different dosages (0, 1, 2, 3) of Waxy gene in the endosperm. The amylose content of starch and proportions of branch chains of DP 17-30 and extra-long branch chains (DP>100) of amylopectin were positively correlated with the Waxy-gene dosage. Proportions of short (DP<17) and long branch-chains (DP 30-80), however, were negatively correlated with the Waxy-gene dosage. The gelatinization conclusion-temperature and temperature-range of the starch were negatively correlated with the Waxy-gene dosage, indicating that amylose facilitated dissociation of the surrounding crystalline regions. These results helped us understand the function of granule-bound starch synthase I in the biosynthesis of amylose and amylopectin and impacts of Waxy-gene dosages on the properties of corn starch., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Granule-bound starch synthase I (GBSS I) plays an important role in the synthesis of amylose and in the determination of starch properties in barley grains. Genomic DNAs for the Waxy gene encoding GBSS I protein were sequenced from 34 barley accessions or lines from Qinghai-Tibet plateau in China, to identify Waxy gene nucleotide variations and study the roles of polymorphic sites of the Waxy gene on expression levels of Waxy transcripts and GBSS I proteins and on resulting starch properties. A total of 116 DNA polymorphic sites were identified within the barley Waxy gene, which divided the studied accessions into 11 haplotypes. Among 33 nucleotide polymorphic sites in coding regions, 5 SNPs in three exons were found to play different roles on the expression level of the Waxy transcript and the GBSS I protein and on the amylose content and starch properties. One SNP G(3935)-to-T substitution in the 10th exon in the accession Z999 (HP II-2) caused a high expression level of the Waxy transcript and the GBSS I protein and the amylose free phenotype. The other SNP alteration was a C(2453)-to-T in the fifth exon in the accession Z1191 (HP I-5), which drastically reduced the expression level of the Waxy transcript and the GBSS I protein and, finally, produced the amylose free phenotype. Three SNPs in the seventh exon in the accession Z1337 (HP I-6) did not significantly change the level of Waxy transcript, the GBSS I protein, and starch properties, except obviously reducing the breakdown value of starch viscosity and extending the peak time. A total of 84 DNA polymorphic sites were found in the noncoding regions. A 403 bp deletion at 5'UTR in the accession Z1979 (HP I-3) had low transcript level, low GBSS I protein level, and low amylose content due to the deletion of cis-acting DNA regulatory elements. A 191 bp insertion and a 15 bp insertion in the first intron and second exons, respectively, may be closely related to a higher transcript level of the Waxy gene and significant differences in some starch properties of the Waxy I DNA group as compared to the Waxy II DNA group. This study indicates the specific variations of the Waxy gene have a great effect on amylose synthesis and starch properties of hull-less barley, which could be very useful to produce new barley with variable starch properties.

The effect of UV-irradiation on four different types of native starch (corn, waxy corn, wheat and potato) have been investigated. Although the changes in the chemical structure of starch specimens were small, indicating good photostability, the samples lost adsorbed water and their crystallinity degree decreased after irradiation. Moreover, a drop in average molecular weight occurred in samples (with the exception of potato starch) as a result of main chain scission. The variations in the properties of investigated specimens of various origin were related to the differences in their structure and macromolecular arrangement. The lowest photostability among the four starches was exhibited by potato starch., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Potato starch is widely utilized in the food industry. Gamma irradiation is a cost-effective and environmentally friendly method for starch modification. Nevertheless, there is a scarcity of comprehensive and consistent knowledge regarding the physicochemical characteristics of high-dose gamma-irradiated potato starch, retrogradation properties in particular. In this study, potato starch was exposed to gamma rays at doses of 0, 30, 60, 90, and 120 kGy. Various physicochemical properties, including retrogradation characteristics, were investigated. Generally, the apparent amylose content (AAC), water absorption, gel viscosity, gel hardness, and gumminess decreased as the doses of gamma irradiation increased. Conversely, the resistant starch (RS), amylose content evaluated by the concanavalin A precipitation method, water solubility, and enthalpy of gelatinization were increased. Additionally, swelling power, crystalline structure, and amylopectin branch chain length distribution either remained stable or exhibited only minor changes. Notably, the degree of retrogradation of potato starches on day 7 was positively correlated with the doses of gamma irradiation. [ABSTRACT FROM AUTHOR]

In recent days, there has been a noticeable surge in demand for high-quality rice. However, the influences of salinity on the quality and starch properties of high-quality rice remain unclear. Three high-quality rice cultivars (Nanjing 9108, Nanjing 5055, and Nanjing 46) were studied to investigate the responses of grain quality to salt stress. There were three treatments, including a control zero salt level (0 g·kg−1, CK), and two salt levels of 0.1 g·kg−1 (0.1% salt stress, T1) and 0.2 g·kg−1 (0.2% salt stress, T2). The study involved the assessment of the appearance, milling, cooking, and eating qualities of rice. We also conducted an analysis of pasting properties, an evaluation of starch thermal properties, and an examination of the fine structure of amylopectin. The findings suggest that as the level of salt stress increases, the yield of rice gradually declines, which is primarily due to a significant reduction in the total spikelet number and the ratio of filled grains. Compared with CK treatment, the appearance and milling quality of rice were significantly improved within the T1 treatment. In addition, the protein concentration and amylose concentration were significantly decreased, the gel consistency was significantly increased, and the cooking and eating qualities were improved. In terms of starch properties, the peak viscosity, breakdown value, infrared ratio (1022/995), and short-chain-length amylopectin ratio increased significantly, while the setback value, pasting temperature, gelatinization enthalpy, relative crystallinity, and infrared ratio (1045/1022) decreased significantly. When comparing T2 with CK, the appearance quality and cooking and eating quality had deteriorated, and the milling quality was improved. The changes in the structural and physicochemical properties of starch were opposite to those in the comparison between the T1 treatment and the CK group. Accordingly, we propose that moderate salt stress has the potential to enhance rice quality, even though there may be a slight decrease in yield. This indicates that it is feasible to cultivate high-quality rice in saline–alkali beach areas. [ABSTRACT FROM AUTHOR]

Nitrogen has a critical influence on the yield and quality of proso millet. However, the exact impact of nitrogen on the cooking quality of proso millet is not clear. In this study, the cooking quality and starch properties of two proso millet varieties (waxy‐Shaanxi millet [wSM] variety and non‐waxy‐Shaanxi millet [nSM] variety) were compared and analyzed under nitrogen fertilizer treatment (N150, 150 kg/hm2) and a control group without nitrogen application (N0, 0 kg/hm2). Compared with the N0 group, the N150 treatment significantly increased protein content, amylose levels, and total yield. Employing rapid visco analyser and differential scanning calorimetry analyses, we observed that under the N150 treatment, the peak viscosity and breakdown viscosity of proso millet powder were diminished, while the setback viscosity and enthalpy values (ΔH) increased. In addition, nitrogen treatment increased the solids content in the obtained rice soup and significantly hardened the texture of the rice. At the same time, we noticed that the absorption capacity of starch in water and oil was enhanced. These results showed that nitrogen fertilizer had significant effects on the cooking quality and starch properties of proso millet. [ABSTRACT FROM AUTHOR]

Besides increasing grain yield, improving rice (Oryza sativa L.) quality has been paid more and more attention recently. Cooking and eating quality (CEQ) is an important indicator of rice quality. Since CEQs are quantitative traits and challenging for measurement, efforts have mainly focused on two major genes, Wx and SSIIa. Chalkiness and floury endosperm significantly affect the eating quality of rice, leading to noticeable changes in CEQ. Due to the easily observable phenotype of floury endosperm, cloning single gene mutations that cause floury endosperm and evaluating changes in CEQs indirectly facilitate the exploration of the minor genes controlling CEQ. In this study, eight mutants with different degrees of floury endosperm, generated through ethylmethane sulfonate (EMS) mutagenesis, were analyzed. These mutants exhibited wide variation in starch morphology and CEQs. Particularly, the z2 mutant showed spherical starch granules significantly increased rapid visco analyzer (RVA) indexes and urea swelling, while the z4 mutant displayed extremely sharp starch granules and significantly decreased RVA indexes and urea swelling compared to the wild type. Additionally, these mutants still maintained correlations with certain RVA profiles, suggesting that the genes PUL, which affect these indexes, may not undergo mutation. Cloning these mutated genes in the future, especially in z2 and z4, will enhance the genetic network of rice eating quality and hold significant importance for molecular marker-assisted breeding to improve rice quality. [ABSTRACT FROM AUTHOR]

Summary: Although dried noodles have been industrialised for many years, some technical bottlenecks, such as dense cross‐section structure, poor rehydration ability and the lack of nutritional and flavour substances, still need to be addressed. Fermentation has been used to produce dried noodles to impart a porous structure and microbial metabolites, improving their rehydration properties and the nutritional and flavour quality of dried noodles. However, the current commercially fermented dried noodles exhibit some issues, such as high breakage rate, rough surface and sticky texture that need to be solved. Drying at high (HT) and ultra‐high temperatures (UT) has been shown to improve the quality of dried pasta or noodles. However, HT and UT drying are not currently used to produce fermented dried noodles. This article investigates the changes in the quality and starch physicochemical properties of fermented dried noodles with high (HM), medium (MM) or low moisture (LM) content dried at HT or UT. The results showed that the UT‐LM condition most prominently improved the noodle quality, significantly reduced the cooking loss rate (5.19%) and significantly increased the water absorption rate (191.41%) of the noodles, and improved the rehydration of noodles. In addition, the cross‐linking of the gluten network was analysed using confocal laser scanning microscopy and the AngioTool software. It was found that the UT treatment promoted the cross‐linking of the gluten network, and the highest number of cross‐linking points (976) was achieved under the UT‐LM condition. The tight gluten network reduces the amylose leaching from the noodles, giving the noodles a denser surface structure and lower adhesiveness. In conclusion, UT‐LM drying could be used as an effective drying condition to improve the quality of fermented dried noodles. [ABSTRACT FROM AUTHOR]

Summary: Considering the high interest in using pulses in the production of staple foods, including pasta, this study aimed at investigating the effect of pre‐gelatinisation on the overall quality of pasta from red lentils. Pre‐gelatinized flours showed a lower gelatinisation temperature (up to about 57 °C vs. about 65 °C) and higher retrogradation tendency than native flour. Such changes resulted in higher water absorption capacity (up to 1.23 vs. 0.98 g g−1) and higher farinographic torque, but did not impact the cooking quality. Conversely, the resistant starch content of cooked pasta decreased (from 14.79 to 10.4 g/100 g total starch) and the starch hydrolysis index increased (from 48.28 to 67.71) when pre‐gelatinised flours were used. In conclusion, pre‐gelatinisation impacted starch, hydration and the mixing properties of red lentils flours, without compromising the cooking behaviour of the related pasta. [ABSTRACT FROM AUTHOR]

Foods with high amylose and resistant starch (RS) contents have great potential to enhance human health. In this study, cassava soluble starch synthase MeSSIII-1 gene mutants were generated using CRISPR/Cas9 system. The results showed that the storage roots of messiii-1 mutants had higher contents of amylose, RS, and total starch than those in CK. The rates of small and large-sized starch granules were increased. Additionally, amylopectin starch in messiii-1 mutants had a higher proportion of medium- and long- chains, and a lower proportion of short-chains than those in CK. The onset, peak, and conclusion temperatures of starch gelatinization in messiii-1 mutants were significantly lower than those in CK, and the peak viscosity, trough viscosity and final viscosity all increased. MeSSIII-1 mutation could increase the contents of sucrose, glucose, and fructose in cassava storage roots. We hypothesize that these soluble sugars serve a dual role: they provide the necessary carbon source for starch synthesis and act as sugar signals to trigger the transcriptional reprogramming of genes involved in starch biosynthesis. This process results in a collective enhancement of amylose, RS, and total starch contents, accompanied by changes in starch granule morphology, fine structure, and physicochemical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

The reaction between starch granules and octenyl succinic anhydride (OSA) is regularly retarded due to the low breakthrough of large oily OSA droplets into starch granules in an aqueous reaction system. Furthermore, high-speed shearing is widely used in the food industry, demanding high shear, cavitation, and collision force. In this sense, high-speed shearing could reduce the size of OSA droplets and promote a more homogeneous distribution of groups in the starch granule. The aim of this study was to evaluate the impact of OSA potato starch synthesis assisted by high-speed shear on structure (SEM and FTIR), gelatinization, rheology, and emulsifying activity (ES and AS) was investigated. The results showed a gradual increase in DS proportional to the applied speed. Likewise, the OSA starches showed a slight alteration in the shape of the granules (SEM), and FT-IR spectroscopy showed a characteristic absorption of the ester carbonyl groups in the OSA starch at 1724 cm-1 . The high-speed shear-treated starches exhibited a significant change in the reduction of the initial gelatinization temperature, although not in the enthalpy. All the gels presented rheology adjusted to the Herschel-Bulkley model with variations in the initial shear stress. Changes in the viscoelastic behavior are proportional to the shear rate detected. High-speed shear treatment did not show a significant effect on emulsion stability (ES) and emulsion activity (EA). Consequently, applying high shear rates allows having OSA starches with different uses. [ABSTRACT FROM AUTHOR]

Granule-bound starch synthase I (HvGBSSI) is encoded by the barley waxy (Wx-1) gene and is the sole enzyme in the synthesis of amylose. Here, a Wx-1 mutant was identified from an ethyl methane sulfonate (EMS)-mutagenized barley population. There were two single-base mutations G1086A and A2424G in Wx-1 in the mutant (M2-1105). The G1086A mutation is located at the 3' splicing receptor (AG) site of the fourth intron, resulting in an abnormal RNA splicing. The A2424G mutation was a synonymous mutation in the ninth intron. The pre-mRNA of Wx-1 was incorrectly spliced and transcribed into two abnormal transcripts. The type I transcript had a 6 bp deletion in the 5' of fifth exon, leading to a translated HvGBSSI protein lacking two amino acids with a decreased starch-binding capacity. In the type II transcript, the fourth intron was incorrectly cleaved and retained, resulting in the premature termination of the barley Wx-1 gene. The mutations in the Wx-1 decreased the enzymatic activity of the HvGBSSI enzyme and resulted in a decreased level in amylose content. This work sheds light on a new Wx-1 gene inaction mechanism. [ABSTRACT FROM AUTHOR]

The microwave is widely applied to process cereals and grains. However, its effects on their chemical components are still not explored clearly. In this study, millet kernels are treated by microwave. The physical and chemical properties of starch in microwave‐treated millet kernels (SMM) are investigated and compared to those in untreated millet kernels (SUM). The experimental results indicate that the peak viscosity of SMM reduces with the increase of microwave time and initial moisture content of millet kernels (IMM). The peak viscosity of SUM is 831.00 BU. Compared with that of SUM, the peak viscosity of SMM decreases after microwave treatment (MT). When the IMM is 35%, the peak viscosity of SMM decreases by 66.23%. MT significantly increases (p < 0.05) the rapidly digestible starch (RDS) and slowly digestible starch (SDS) content of SMM, which reduces its resistant starch (RS) content. Under MT time of 150 s, the SDS of SMM is up to 35.92%. When the IMM is 35%, after MT, the RDS content of SMM reaches 52.10%. Additionally, the relative crystallinity and short‐range order of SMM are both decreased after MT. Therefore, the microwave is a useful tool for improving the properties of the starch in millet. [ABSTRACT FROM AUTHOR]

Summary: To investigate the effects of seven starches made from different crop sources on noodle quality, Chinese dried noodles made from various reconstituted flours were prepared and analysed. Potato starch had better solubility and swelling power than the other starches, leading to higher water absorption, cooking loss and breakage ratio of the potato starch noodles. The correlation results unravelled that the cooking breakage ratio of noodles presented positive correlations with solubility, swelling power, peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) values of starches. Besides, the adhesiveness of noodles showed a positive correlation with conclusion temperature (Tc) and setback viscosity (SV) values of starches. Moreover, the peak temperature (Tp) value of starches was negatively correlated with cooking loss; the granule size of starches had a positive correlation with noodles water absorption; and the peak time (PkT) value of starches represented positive relationships with noodles chewiness, shearing force and breaking strength. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nitrogen is an important factor that influences the yield and quality of wheat grain. However, little is known about its effect on the different positions of the grain in spikelets. Compared with the control group, nitrogen application increased the weight, starch content, and protein content of grains in each position considerably. In particular, the protein content in high grain positions of Yangmai 13 (YM 13) under nitrogen treatment are similar to those positions in Yannong 19 (YN 19) under normal levels. Nitrogen application substantially increased the volume proportion of small starch granules and the average degree of polymerization (DP) but reduced the apparent amylose content (AAC), and the breakdown values (BV) of the first grain (G1) and the second grain (G2) in YN19. Nitrogen application considerably increased AAC, the volume proportion of small starch granules, and the ordered structure of starch surface of G1 and AAC, BV, and DP of G2 in YM13. These results demonstrated that a medium nitrogen level is conducive to increase the agronomic traits in high‐position grains and a better pasting properties of starch in low‐position grains. [ABSTRACT FROM AUTHOR]

In this study, we investigated the starch properties of Aegilops sharonensis (R7), tetraploid wheat (Z636), and their amphidiploid (Z636 × R7). The results of protein electrophoresis showed that waxy protein of Ae. sharonensis (R7) and tetraploid wheat (Z636) is expressed in the amphidiploid (Z636 × R7). The total starch content and amylose content of the amphidiploid (Z636 × R7) were higher than Ae. sharonensis (R7) and lower than tetraploid wheat (Z636). The amphidiploid (Z636 × R7) exhibits an intermediate type of starch granules morphology that the ratio of A/B-type starch granules and their shapes ranged between Ae. sharonensis and tetraploid wheat. The gelatinization parameters showed that the concluding temperature (Tc) and enthalpy change (ΔH) of Ae. sharonensis (R7) were significantly lower than those of tetraploid wheat (Z636) and the amphidiploid (Z636 × R7), while the values of onset temperature (To) and peak temperature (Tp) were similar among the Ae. sharonensis (R7), tetraploid wheat (Z636), and the amphidiploid (Z636 × R7). For the aging properties, the ΔH values of Ae. sharonensis (R7) and the amphidiploid (Z636 × R7) were close but lower than that of tetraploid wheat (Z636), whereas the parameters of To, Tp, and Tc did not differ significantly among three materials. The amphidiploid (Z636 × R7) possesses varied starch properties from wheat, which may be useful in wheat quality improvement. [ABSTRACT FROM AUTHOR]

A novel technique has been developed to increase γ-aminobutyric acid levels and enhance the quality of germinated brown rice (GBR) by ultrasound and enzyme treatment. The combined use of ultrasonic and enzyme treatments notably enhanced the germination rate of brown rice. Additionally, the γ-aminobutyric acid content substantially improved from 18.79 ± 1.87 mg/100 g to 38.60 ± 3.19 mg/100 g when compared to the untreated group. Moreover, the cracks produced on the GBR surface and disruption of the starch structure resulted in increased water absorption, shortening of cooking time, and reduction in GBR hardness, thereby improving the cooking and edible quality of GBR. Additionally, ultrasonic and enzyme treatments increased the amount of fast-digestible starch and enhanced starch digestibility. However, they had minimal impact on the crystal structure, degree of crystallinity, and heat energy changes during the starch pasting process of GBR. [Display omitted] • Ultrasonic-enzyme treatment increases γ-aminobutyric acid levels. • Ultrasonic-enzyme treatment improves edible quality of germinated brown rice. • Ultrasonic-enzyme treatment destroys the cortex and starch structure. • Ultrasonic-enzyme treatment improves digestive property of germinated brown rice. [ABSTRACT FROM AUTHOR]

Corn starch was chemically modified by cross-linking with Sodium tri meta phosphate (STMP)/ Sodium tripolyphosphate (STPP( (99:1 W/W) and the physicochemical properties of the cross-linked corn starch were vstigated as a function of the degree of cross-linking. Crosslinking decreased the solubility, swelling factor, and paste clarity of corn starch. While the viscosity significantly increased from the native starch and there was a slight increase of sediment volume. The swelling factor was highly correlated with the degree of crosslinking, the X-ray iffraction atterns did not show any significant alteration in the crystallinity of corn starch. It was by Scanning Electron Microscopy (SEM) measurement that a black zone was observed on the surface of modified starch granules as compared with native starch granules. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The two types of HA compound fertilizers exerted increasing effects on DM in storage roots and storage root yield. • The two types of HA compound fertilizers increased the total starch content and AP content by increasing the activities of AGPase, UGPase and SSS in storage roots during the medium and latter growth stages. • The two types of HA compound fertilizers decreased the volume-weighted mean diameter of starch particles but showed little effect on the viscosity properties (e.g., PV, HPV and CPV) and thermal properties of starch gelatinization (e.g., T o , T c and ΔH). • 750 kg ha−1 HA compound fertilizer (2.6 % HA, 10–8–24 N-P 2 O 5 -K 2 O) was the most conducive to improving storage root yield and starch yield for variety Jishu 25. In recent years, although humic acid (HA) compound fertilizers have been applied in sweet potato production, limited research has specifically addressed their impacts on dry matter (DM) accumulation, starch yield and starch properties, particularly in varieties with high starch content. To assess these effects, five treatments were designed for the high-starch variety Jishu 25 as follows: no fertilizer application (CK), chemical fertilizer with 75–60–180 kg ha−1 N-P 2 O 5 -K 2 O (F1), 750 kg ha−1 HA compound fertilizer with 2.6 % HA and 10–8–24 N-P 2 O 5 -K 2 O (F2), chemical fertilizer with 112.5–67.5–157.5 kg ha−1 N P 2 O 5 K 2 O (F3), 750 kg ha−1 HA compound fertilizer with 3 % HA, and 15–9–21 N-P 2 O 5 -K 2 O (F4). The results indicated that F2 and F4 reduced the DM distribution ratio in leaves and stems, concurrently increasing DM accumulation in tuberous roots compared to F1 and F3. These HA fertilizer treatments enhanced the activities of AGPase, UGPase and SSS in tuberous roots during the middle and late growth stages, resulting in elevated total starch content and amylopectin content at harvest. Both types of HA fertilizers decreased the D [4,3] of starch particles, but exhibited minimal effects on PV, HPV, CPV, T o , T c and ΔH. The highest tuberous root yield and starch yield were observed after applying F2 continuously for two years. In conclusion, for optimizing starch yield while preserving its quality, the application of 750 kg ha−1 HA compound fertilizer with 2.6 % HA and 10–8–24 N-P 2 O 5 -K 2 O proved to be most advantageous for sweet potato producers cultivating this high-starch variety in regions with a similar climate in northern China. [ABSTRACT FROM AUTHOR]

Interests in using high-amylose maize (HAM) flour and starch for low glycemic index foods continue to grow. The objective of this work was to understand resistant-starch formation during drying the HAM kernels. Freshly harvested HAM kernels with 28.2 % initial moisture were subjected to sun drying (~30 °C) or hot-air drying at 50 °C, 70 °C, 90 °C, or 110 °C. The enzymatic digestibility of HAM flour decreased from 63.6 % to 41.1 % as the drying temperature increased from 30 °C to 110 °C. The swelling power, solubility, and overall viscosity of HAM flours milled from kernels dried at 110 °C decreased, whereas the peak and conclusion gelatinization temperatures, enthalpy change, and relative crystallinity increased compared to those of flours from kernels dried at 30 °C, 50 °C, 70 °C, and 90 °C. Light microscopic and scanning electron microscopic images showed that starch granule aggregation in HAM flour increased with increasing drying-temperatures. The aggregates remained after 16 h enzymatic hydrolysis of cooked HAM flours. These results suggested that the increase of enzymatic resistance of HAM flour resulted from the formation of high temperature-resistant ordered structures in starch granules and the starch aggregates less accessible to enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]

Local people in Sarawak, Malaysia produce sago starch, commonly referred as lemantak, using traditional method for authentic meals and delicacies. The quality of lemantak degrades with time due to its high moisture content limiting the potential for a wider market, and hence affecting the socio-economy of those whose livelihood depends on sago starch production. The objective of the present work was to evaluate the changes in the properties of traditionally processed dried Sarawak sago starch. In order to achieve this, sago starch was extracted using a well-established traditional process and was dried at 40°C to produce sago starch with moisture contents of 40%, 30%, 20% and 10% wet basis. The effect of moisture content on the physical properties was studied through colour analysis, microscopic analysis, and particle size distribution. Analysis on resistant starch content was also performed. Changes on the hydration and functional properties was monitored by measuring the water absorption index (WAI), water solubility index (WSI), swelling capacity (SC), and gelatinisation behaviour. Lastly, Fourier transform-infrared spectroscopy (FT-IR) was applied to observe the changes in amorphous and crystalline areas. The physical properties analysis showed changes in starch colour and granule surface; but the change on granule size varied. Dried starch with lower moisture content exhibited higher resistant starch, absorption index, and peak temperature, but lower solubility index, swelling capacity, peak viscosity, crystalline index, and amorphous index. It is suggested that moisture content affected the changes in traditionally processed sago starch properties which was influenced by few components namely polyphenol, lipid, amylose-lipid complex, and inter-molecular hydrogen bond. [ABSTRACT FROM AUTHOR]

Recent findings suggest that optimal application of nitrogen fertilizers can effectively improve the quality of proso millet (PM). Here, we aimed to investigate the pathways associated with starch synthesis and metabolism to elucidate the effect and molecular mechanisms of nitrogen fertilization in starch synthesis and properties in waxy and non-waxy PM varieties using transcriptomic techniques. Co-expression network analysis revealed that the regulation of starch synthesis and quality in PM by nitrogen fertilizer mainly occurred in the S2 and S3 stages during grain filling. Nitrogen fertilization inhibited glycolysis/gluconeogenesis and starch biosynthesis in grains, but increased starch degradation to maltose and dextrin and then to glucose. Moreover, nitrogen fertilization increased starch accumulation by upregulating the expression of SuS and malZ genes, thereby increasing the total starch content in grains. In contrast, nitrogen fertilization suppressed the expression of GBSS gene and decreased amylose content in PM grains, resulting in a relatively higher crystallinity, light transmittance, and breakdown viscosity in the two PM varieties. Overall, these results provided transcriptomics insights into the molecular mechanisms by which nitrogen fertilization regulates starch quality in PM, identified key genes that associated with the starch properties, and provided new insights into the quality cultivation of PM. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of the time of heat-moisture treatment (HMT) of oat grains in husk on lipase activity, pasting properties of flour, and properties of starch isolated from grains. Oat grains with 13% moisture were subjected to 15, 30, 45, and 60 min of HMTat 110°C. Starches of heat-moisture-treated oat grains were isolated with the alkaline method. The 60-min HMT suppressed more than 60% of the lipase activity of oat grains and increased the extraction yield of oat starch. HMT also reduced swelling power, solubility, gelatinisation enthalpy, and relative crystallinity of starches isolated from oat grains. The reduction of breakdown and retrogradation of oat flour promoted by 60 min of HMT provides better paste stability, and thus can be used for canned and frozen foods. [ABSTRACT FROM AUTHOR]

Fruit wastes constituting up to half of total fruit weight represent a large pool of untapped resources for isolation of starch with diverse applications. In this work, the possibility of isolating starch from tropical fruit wastes and its extended application as a natural coagulant was elucidated. Amongst the 12 various parts of fruit wastes selected, only jackfruit seeds contained more than 50% of total starch content. Using alkaline extraction procedures, starch has been successfully isolated from local jackfruit seeds with a yield of approximately 18%. Bell-shaped starch granules were observed under SEM with a granule size ranging from 1.1 to 41.6 μm. Detailed starch characteristics were performed to provide a comparison between the isolated seed starch and also conventional starches. Among them, chemical properties such as the content of starch, amylose, amylopectin and the corresponding molecular weights are some of the key characteristics which governed their performance as natural coagulants. The potential use of isolated seed starch as an aid was then demonstrated in both suspensions of kaolin (model synthetic system) and Chlorella sp. microalga (real-time application) with plausible outcomes. At optimized starch dosage of 60 mg/L, the overall turbidity removal in kaolin was enhanced by at least 25% at a fixed alum dosage of 2.1 mg/L. Positive turbidity and COD removals were also observed in the treatment of Chlorella suspensions. Starches which served as bridging agents aided in the linkage of neighbouring microflocs and subsequently, forming macroflocs through a secondary coagulation mechanism: adsorption and bridging. [ABSTRACT FROM AUTHOR]

The nutrient composition and starch properties of eight potato cultivars (Electra, Fianna, Innovator, Mondial, Navigator, Panamera, Savanna and Sifra) were evaluated, to determine their value to human nutrition and to inform decisions for culinary usage. Potatoes that had been cultivated under the same agronomic conditions were used. The results showed that there were significant differences ( P < 0.05) in the parameters measured. Fianna and Innovator had the highest dry mass of 22 and 21%, respectively, while Electra had the lowest (16%). Innovator, together with Navigator, displayed the highest starch content (17.9% fresh weight [fw]), with the highest proportion of amylose (27.2% dry weight [dw]). However, Fianna and Panamera had the highest protein content (2.87 and 2.53% fw, respectively). Electra had the highest calcium (10.2 g 100 g −1 fw) and iron (2.91 g 100 g −1 fw) content. This represents a contribution of 3 and 32%, respectively, to the population-weighted estimated average dietary requirement of Africa. Innovator also contained the lowest aluminium contribution (12%) to the tolerable weekly intake limit set by the FAO. In addition to low amylose, the starch of Mondial had a high swelling power, oil absorption capacity and gelatinisation enthalpy, and a greater frequency of small-sized granules. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of freezing rate and storage time on the properties of frozen wheat dough starch. The dough was frozen at either slow (−0.14°C/min) or fast (−1.75°C/min) rates and stored at −20°C for 8 weeks. Every 2 weeks, the frozen dough was sampled and freeze-dried. Analyses of the dried dough included damaged starch, paste properties, and thermal, morphological, and structural properties. Damaged starch increased significantly during storage, and it was higher in the dough frozen at a slow rate than in the dough frozen at a fast rate. The peak viscosity during storage gradually but significantly decreased. During this period, the peak viscosity was higher for the dough frozen at a slow rate than the dough frozen at a fast rate. The enthalpy of starch crystallite fusion gradually but significantly increased during storage, and it was lower in the dough frozen at a slow rate than in the dough frozen at a fast rate. The structural properties show a decrease in the crystalline percent as a result of the freezing and storage time. SEM images show that starch granules were separated from the gluten matrix after storage, and separation was greater for the dough frozen at a fast rate than that frozen at a slow rate. The freezing rate and storage time increased starch damage and changed the microstructure of the dough. [ABSTRACT FROM AUTHOR]

The aim of this study, was to evaluate the effect of extrusion conditions and particle size index on the starch properties of expanded nixtamalized snacks elaborated with whole blue corn. Whole grains were ground to achieve two different particle size indexes (PSI), 83.9 and 94.1, and were extruded at three feed moistures (14, 16.5, and 20.5%). The data suggested that the severity of milling and the extrusion process resulted in higher starch degradation, specifically in the snacks obtained with a feed moisture of 20.5%, which showed the higher values of starch damage. Nixtamalization by extrusion produced minimum amounts of resistant starch, mainly as retrograded starch and amylose-lipid complex, as demonstrated by thermal and structural analyses. Snacks produced with feed moisture of 16.5-20.5% and a PSI of 94.1 showed the highest values of resistant starch. The rheological properties of snacks with PSI of 83.9 indicated lower starch degradation and presented lower amounts of resistant starch than snacks with higher PSI. The feed moisture affected all the parameters evaluated in the snacks more than the PSI. [ABSTRACT FROM AUTHOR]

• The springiness of noodles can be represented by quantificating microstructure. • Denser gluten network formation during processing increased noodles springiness. • Rising swelling power decreased the compactness of the network in dough sheet. • Lower swelling power reduced average network length and width of cooked noodles. • The addition of starch with lower swelling power could enhance noodle springiness. Understanding the effect of starch properties on the gluten network during noodle-making will allow rational selection of ingredients. The microstructure and texture of dough sheets, dried noodles, and cooked noodles prepared by adding different wheat starches were compared. Increasing starch solubility and swelling power could reduce the compactness and homogeneity of the network in dough sheet. Lower swelling power and higher solubility of starch made the elastic modulus of dried noodles increase, leading to increasing branching rate along with decreasing average network width and length of cooked noodles. After cooking, noodles with increasing springiness showed higher branching rate of gluten network in dough sheet, greater elastic modulus of dried noodles, and lower average network length of cooked noodles. It was thus proposed that wheat starch with lower swelling power could enhance the springiness of noodles. The quantitative analysis of microstructure was an appropriate method to predict the noodle springiness. [ABSTRACT FROM AUTHOR]

Background: Starch is biosynthesised by a complex of enzymes including various starch synthases and starch branching and debranching enzymes, amongst others. The role of all these enzymes has been investigated using gene silencing or genetic knockouts, but there are few examples of overexpression due to the problems of either cloning large genomic fragments or the toxicity of functional cDNAs to bacteria during cloning. The aim of this study was to investigate the function of potato STARCH BRANCHING ENZYME II (SBEII) using overexpression in potato tubers. Results: A hybrid SBEII intragene consisting of potato cDNA containing a fragment of potato genomic DNA that included a single intron was used in order to prevent bacterial translation during cloning. A population of 20 transgenic potato plants exhibiting SBEII overexpression was generated. Compared with wild-type, starch from these tubers possessed an increased degree of amylopectin branching, with more short chains of degree of polymerisation (DP) 6-12 and particularly of DP6. Transgenic lines expressing a GRANULE-BOUND STARCH SYNTHASE (GBSS) RNAi construct were also generated for comparison and exhibited post-transcriptional gene silencing of GBSS and reduced amylose content in the starch. Both transgenic modifications did not affect granule morphology but reduced starch peak viscosity. In starch from SBEII-overexpressing lines, the increased ratio of short to long amylopectin branches facilitated gelatinisation, which occurred at a reduced temperature (by up to 3°C) or lower urea concentration. In contrast, silencing of GBSS increased the gelatinisation temperature by 4°C, and starch required a higher urea concentration for gelatinisation. In lines with a range of SBEII overexpression, the magnitude of the increase in SBEII activity, reduction in onset of gelatinisation temperature and increase in starch swollen pellet volume were highly correlated, consistent with reports that starch swelling is greatly dependent upon the amylopectin branching pattern. Conclusion: This work reports the first time that overexpression of SBEII has been achieved in a non-cereal plant. The data show that overexpression of SBEII using a simple single-intron hybrid intragene is an effective way to modify potato starch physicochemical properties, and indicate that an increased ratio of short to long amylopectin branches produces commercially beneficial changes in starch properties such as reduced gelatinisation temperature, reduced viscosity and increased swelling volume. [ABSTRACT FROM AUTHOR]

Starch continues to be an important renewable biopolymer in both the food and non-food industries. Its properties, which vary depending on the plant source, stem directly from its structure. The recent substantial increase in knowledge of the molecular structure of starch components and the architecture of starch granules has contributed significantly to an enhanced understanding of the structural base of starch functionality. This résumé provides an overview of the present views of the starch structure-function relationships with an emphasis on industrially important starch sources. [ABSTRACT FROM AUTHOR]