Mechanism of highland barley glutenin regulating starch digestion based on core-shell structure: Effect of varying amylose content.

Relationship between the structure, physicochemical properties and in vitro digestibility of rice starches with different amylose contents

Impact of annealing and heat-moisture treatment on rapidly digestible, slowly digestible and resistant starch levels in native and gelatinized corn, pea and lentil starches

Understanding starch behavior under various processing conditions is important for the development of novel food products with tailored nutritional profiles. This study investigated changes to the structure and properties of native corn starch (NCS) and biomimetic starch-entrapped microspheres following thermal and enzymatic treatments. Heat-treated microspheres showed more birefringence and structural order than native starch, indicating incomplete gelatinization due to the alginate matrix. Microspheres (MC-1 and MC-2) exhibited lower pasting viscosities. Larger particles retarded viscosity development. Enzyme kinetics showed higher apparent maximum reaction velocity (Vm) but an increased Michaelis constant (Km) for microspheres in comparison with native starch. The elevated Km reflects reduced enzyme affinity due to the alginate barrier, and the higher Vm results from transiently high local substrate concentration on the surface. Digestion progressed from the outer layer toward the core, with MC-2 retaining higher crystallinity and structural integrity after 120 min because of the protective effect of the alginate matrix. Thermal analysis demonstrated that gelatinization onset (Tₒ), peak (Tp), and conclusion (Tc) temperatures increased with digestion time in all samples and the enthalpy change (ΔH) decreased, consistent with structural reordering after digestion. The alginate shell in microspheres effectively delayed amorphous region hydrolysis, enhancing thermal stability. Consequently, the rapidly digestible starch (RDS) content decreased from 84.54% in NCS to 47.06% in MC-2, whereas the resistant starch (RS) and slowly digestible starch (SDS) content increased from 20.42% to 44.21% and from 7.90% to 34.90%, respectively. Alginate encapsulation enhanced the thermal properties of starch and increased its slowly digestible and resistant starch content by forming biomimetic starch-entrapped microspheres. © 2025 Society of Chemical Industry.

This study determined the effect of micronization (high intensity infrared heating) on the concentrations of rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) in normal barley (NB), high-amylose barley (HAB), and waxy barley (WB). The gelatinized starch contents and the thermal properties of the micronized samples also were determined. Samples of each barley type were tempered to each of three moisture contents (approximately 17, 31, or 41%), and then each tempered sample was micronized to each of three surface temperatures (100, 120, or 140 degrees C). Micronized barley samples were substantially lower in RS and in SDS and, therefore, higher in RDS than corresponding unprocessed samples. In general, higher concentrations of RDS and of gelatinized starch were associated with higher initial moisture contents and higher surface temperatures. The lowest concentrations of RS were observed in micronized WB samples. Similar concentrations of RS were observed in corresponding NB and HAB samples. Micronization resulted in slight increases in the onset (To), peak (Tp), and completion (Tc) gelatinization temperatures and in substantial reductions in the gelatinization enthalpy (DeltaH), the latter reflecting the levels of gelatinized starch in micronized samples, particularly in samples micronized at higher moisture contents and to higher surface temperatures. Endothermic transitions were evident only in samples tempered to 17% moisture or 31% moisture (surface temperature of 100 degrees C only).

Digestibility and physicochemical properties of rice (Oryza sativa L.) flours and starches differing in amylose content

Effect of roasted pea flour/starch and encapsulated pea starch incorporation on the in vitro starch digestibility of pea breads

Structure of faba bean, black bean and pinto bean starches at different levels of granule organization and their physicochemical properties

The digestibility of starch is important for the nutritive value of staple food. Although several genes are responsible for resistant starch (RS) and slowly digestible starch (SDS), gaps persist concerning the molecular basis of RS and SDS formation due to the complex genetic mechanisms of starch digestibility. The objective of this study was to identify new genes for starch digestibility in rice and interprete the genetic mechanisms of RS and SDS by GWAS. Genome-wide association studies were conducted by associating the RS and SDS phenotypes of 104 re-sequenced rice lines to an SNP dataset of 2,288,867 sites using a compressed mixed linear model. Candidate genes were identified according to the position of the SNPs based on data from the MSU Rice Genome Annotation Project. Seven quantitative trait loci (QTLs) were detected to be associated with the RS content, among which the SNP 6m1765761 was located on Waxy. Starch branching enzymes IIa (BEIIa) close to QTL qRS-I4 was detected and further identified as a specific candidate gene for RS in INDICA. Two QTLs were associated with SDS, and the LOC_Os09g09360 encoding lipase was identified as a causal gene for SDS. GWAS is a valid strategy to genetically dissect the formation of starch digestion properties in rice. RS formation in grains is dependent on the rice type; lipid might also contribute to starch digestibility and should be an alternative factor to improve rice starch digestibility.

ABSTRACTThe changes of digestibility, several processing properties, and structure of highland barley starch induced by dry heat treatment (DHT), heat moisture treatment (HMT), and annealing treatment (AT) were investigated. And the interrelationship between modification conditions, structure, and functional properties was also investigated. For DHT, the starch was treated at 110°C for 4 , 8, and 12 h, respectively. For HMT, the starch was adjusted to moisture contents of 20%, 25%, and 30%, and then heated at 110°C for 4 h. For AT, the starch was treated at 50°C for 12 and 24 h, respectively. The results indicated that DHT, HMT and AT all positively impacted the total content of slowly digestible starch (SDS) and resistant starch (RS) in the starch samples, and HMT was the best method in leading to the conversion of a portion of rapidly digestible starch (RDS) into SDS and RS. Among them, HMT‐20% resulted in a decrease in the RDS content from 91.19% to 81.50%, while simultaneously causing an increase in the SDS and RS content from 5.54% and 3.27% to 8.73% and 9.77%. Moreover, HMT significantly affected the thermal properties, rheological properties, crystallinity, molecular structure, and particle morphology of starch. Therefore, our research suggested that utilizing hydrothermal treatment or heat treatment could be a potential approach for controlling the digestibility of starch products according to desired specifications. This experiment innovatively focused on highland barley starch, a less‐researched material. Using DHT, HMT, and AT, it measured different digestible starch contents and explored the links between treatment conditions, RS contents, structure, and function, providing new ideas for its application in functional foods.

Laminarin modulates long-term retrogradation-related water migration behavior of different crystalline starches and regulates their structural and digestive properties.

ABSTRACTAlthough the individual effects of hydrothermal treatment, psyllium fiber, and amylose content on starch properties are well understood, their combined interactions remain largely unexplored. This study investigated the impact of heat moisture treatment (HMT) and annealing (ANN), combined with 3% psyllium husk fiber (PHF), on the structural, rheological, and digestibility properties of maize starch with varying amylose content. The starch samples were analyzed for crystallinity, viscosity, and in vitro digestibility. Frequency sweep and FTIR spectra were also determined. Waxy and normal maize starch showed typical A‐type diffraction pattern, while high‐amylose starch exhibited B‐type diffraction pattern. HMT‐treated starches had significantly (p ≤ 0.05) lower peak and final viscosities, while ANN‐treated starches exhibited higher viscosities. HMT and ANN treatments generally increased G', regardless of fiber addition, except for waxy maize starch. Hydrothermal treatments alone had minimal impact on slowly digested starch (SDS) and resistant starch (RS) content, but psyllium significantly increased SDS and RS levels. Findings from the study suggest that combining HMT and ANN with PHF supplementation can significantly modulate starch digestibility, making them suitable for functional food applications with potential health benefits such as diabetes management and improved gut health. Future research should focus on the application of the starch blends in product formulations, as well as the evaluation of their shelf life and sensory properties in the newly developed products.

SummaryInfluence of diverse botanical sources (wheat, maize, waxy maize, cassava, potato, rice or waxy rice) on in vitro native starch digestibility has been investigated. Physicochemical properties (chemical composition, particles size and shape, surface features) of starch granules were determined with a view to explaining digestibility differences between samples. Rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents were measured according to Englyst method. Potato starch was shown to be composed of large rounded granules having smooth surfaces, which explains its slow enzymatic breakdown. Potato starch displayed the highest RS (86%) content and the lowest RDS content (9.9%). Since RS positively influences health and SDS may result in cell, tissue and/or organ damages, potato starch is an ideal starch nutrient. Conversely, waxy rice starch was rich in amylopectin and displayed small diameters and angular shapes, which are both known to facilitate enzymatic starch hydrolysis. It exhibited a near‐zero RS content (0.9%) and a high RDS fraction (60%). According to this study, potato starch exhibited the best nutrient profile, followed up in this order by cassava, waxy maize, wheat, maize and waxy rice starches.

Two wild rice starches were isolated from Erhai in Dali, Yunnan Province (EWR) and Xinghua in Taizhou, Jiangsu Province (XWR), China, and compared with black rice (BR) starches, its structure, gelatinization and starch digestibility in vitro were studied. The results showed that the apparent amylose content of starches in EWR and XWR was 19.82% and 20.33%, respectively. The starch granules were irregular polygons and all were A-type crystals, with relative crystallinity of 25.6%~26.65%, similar short-range ordered structure and layered structure, and the thickness of the semi-crystalline layer ranged from 9.82 nm to 9.97 nm. XWR and EWR starches had exhibited the same gelatinization temperature range, enthalpy of gelatinization (ΔHgel) and swelling power, but XWR starches was higher than EWR in the gelatinization temperature and lower than EWR in the solubility. The rapidly digestible starch (RDS) content of wild rice starches in the two regions was low, only 3.63% and 37.32%, whether it was raw starches or gelatinized starches. After gelatinization, the RDS and slowly digestible starch (SDS) content were significantly increased and the resistant starch (RS) content was decreased, but the RS content was still higher than the common grains. Therefore, the wild rice starches are more suitable for processing and producing resistant starch products. Extracting starch from Chinese wild rice can provide guidance and reference for its application in edible and non-edible products, and promote the development and utilization of Chinese wild rice. Abbreviations: EWR, wild rice from Erhai in Dali, Yunnan Province; XWR, wild rice from Xinghua in Taizhou, Jiangsu Province; RDS, rapidly digestible starch; SDS, slowly digestible starch; RS resistant starch; TS, total starch; To, onset temperature of gelatinization; Tp, peak temperature of gelatinization; Tc, conclusion temperature of gelatinization; ∆Hgel, enthalpy of gelatinization.

Mung bean was subjected to different processing conditions (soaking, germination, cooking and autoclaving) and their textural, pasting and in vitro starch digestibility characteristics were studied. A significant reduction in textural properties (hardness, cohesiveness, gumminess and chewiness) after cooking and autoclaving treatment of mung bean was observed. Flours made from differently processed mung bean showed significant differences (P < 0.05) in their pastin g characteristics. Peak and final viscosity were the highest for flour from germinated mung bean whereas those made from autoclaved mung bean showed the lowest value. in vitro starch digestibility of mung bean flours was assessed enzymatically using modified Englyst method and the parameters studied were readily digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS) and total starch (TS) content. Various processing treatments increased the RDS contents of mung bean, while the SDS content was found to be the highest for soaked and the lowest for the autoclaved sample. Germinated sample showed higher amount of digestible starch (RDS + SDS) as compared to raw and soaked samples. Flours from raw and soaked samples showed significantly low starch hydrolysis rate at all the temperatures with total hydrolysis of 29.9 and 31.2%, respectively at 180min whereas cooked and autoclaved samples showed high hydrolysis rates with 50.2 and 53.8% of these hydrolyzing within 30min of hydrolysis.

Modification by α-d-glucan branching enzyme lowers the in vitro digestibility of starch from different sources