Higher Resistant Starch Content Research Articles

Structural and physicochemical properties of rice starch from a variety with high resistant starch and low amylose content

Structural and physicochemical properties of rice starch from a variety with high resistant starch and low amylose content

Noodles made from blends of rice flour and pineapple stem starch: physical properties, cooking qualities, in vitro starch digestibility and sensory properties

SummaryNoodles are generally made from rice flour, wheat flour or mungbean starch. Interestingly, pineapple stem starch (PSS), an alternative starch derived from pineapple stems as agricultural waste, has not yet been investigated for noodle production. The noodles were then prepared in different ratios of commercial rice flour and PSS (100:0, 70:25, 50:50, 25:75 and 0:100) to investigate the effects of PSS on noodle qualities and properties including physical properties, cooking quality, in vitro starch digestibility and sensory attributes. The results showed that high PSS content had a positive effect on the structure and textural properties of noodles by increasing the network structure, hardness and chewiness, resulting in good sensory quality, which could be due to the high amylose content (30.56%) of PSS. However, the optimal cooking time and the cooking loss of the cooked noodles increased with an increasing proportion of PSS. In addition, noodles with a high PSS content had a higher content of slowly digestible starch and resistant starch, which can have a positive effect on our health. Our results suggest that PSS, an alternative starch from agricultural waste, can replace rice flour to develop better‐quality gluten‐free noodles. Similarly, PSS‐based noodles with a high resistant starch content could benefit human health by lowering the glycemic index and reducing the risk of non‐communicable diseases.

Techno-functional and physicochemical properties of corn flours as potential food ingredients

Background and Objectivescorn plays a crucial role in food security and nutrition. This study aimed to assess the impact of three corn cultivars (Advanta, Leptra, and Porva) and varying particle sizes of flours on estimated glycemic index (eGI), techno-functional properties, and rheological behaviors, crucial in defining their technological properties. FindingsWAI and WSI presented differences among particle sizes for Advanta and Leptra corn flours, whereas Porva flour displayed consistent results regardless of particle sizes. Notably, while Advanta and Leptra did not showed differences in eGI and its fractions, Advanta (174.4 µm) demonstrated the lowest eGI at 32.21, alongside higher water-holding capacity (WHC) compared to wheat flours. Further findings included an initial Emulsification Activity Index (EAI) of 40.55 m2/g and a minimum gelation concentration (LGC) of 12 %. Additionally, rheological characterization indicated a non-Newtonian and pseudoplastic behavior. Conclusionsthis study presented a corn flour with high resistant starch content and low glycemic index with functional properties that could be applied to manufacture healthy food requiring high water solubility, greater emulsification capacity, and water retention capacity greater than conventional flours. Significance and Noveltythe study on intrinsic and extrinsic factors that can modulate the glycemic index of corn becomes crucial. This exploration holds the potential to design healthy commercially viable products.

Effects of crystallization temperature on structure and digestibility of spherulites formed from debranched high-amylose maize starch

High-amylose maize starch (69.3 % amylose) was debranched to increase the level of linear molecules and enhance the formation of spherulites. Debranched high-amylose maize starch (25 %, w/w) was heated to 180 °C in a Parr reactor followed by crystallization at different temperatures between 25 and 150 °C. The objectives of this study were to investigate the effects of crystallization temperature on the yield, morphology, structure, crystallinity, and digestibility of the spherulites formed. When the crystallization temperature was 150 °C, spherulites with negative birefringent sign were formed. High crystallization temperature caused molecular degradation and the degree of degradation was severe at 150 °C, resulting in relatively short chain amylose (DP < 150). When crystallized at 25 to 120 °C, spherulites with strong positive birefringence were produced. The long chain amylose was attributed to the positive birefringence. All spherulites had a predominant B-type crystalline structure. The spherulites with negative birefringence showed a lower degree of crystallinity and lower resistance to enzyme digestion, but all the spherulites with positive birefringence had a high resistant starch content (89–94 %). α-Amylase was not able to penetrate inside the spherulites as revealed by the confocal laser scanning microscopic images.

Ultrasonication followed by aqueous two-phase system for extraction, on-site modification and isolation of microalgal starch with reduced digestibility

Microalgae are new and sustainable sources of starch with higher productivity and flexible production modes than conventional terrestrial crops, but the downstream processes need further development. Here, ultrasonication (with power of 200 W or 300 W and duration of 10, 15, 20, or 25 min) was applied to simultaneously extract and modify starch from a marine microalga Tetraselmis subcordiformis for reducing the digestibility, and an aqueous two-phase system (ATPS) of ethanol/NaH2PO4 was then used to isolate the starches with varied properties. Increasing ultrasonic duration facilitated the partition of starch into the bottom pellet, while enhancing the ultrasonic power was conducive to the allocation in the interphase of the ATPS. The overall starch recovery yield reached 73 ∼ 87 % and showed no significant difference among the ultrasonic conditions tested. The sequential ultrasonication-ATPS process successfully enriched the starch with purities up to 65 % ∼ 88 %, which was among the top levels reported in microalgal starch isolated. Ultrasonication produced more amylose which was mainly fractionated into the interface of the ATPS. The digestibility of the starch was altered under different ultrasonic conditions and varied from different ATPS phases as well, with the one under the ultrasonic power of 200 W for 15 min at the bottom pellet having the highest resistant starch content (RS, 39.7 %). The structural and compositional analysis evidenced that the ultrasonication-ATPS process could exert impacts on the digestibility through altering the surface roughness and fissures of the starch granules, modulating the impurity compositions (protein and lipid) that could interact with starch, and modifying the long- and short-range ordered structures. The developed ultrasonication-ATPS process provided novel insights into the mechanism and strategy for efficient production of functional starch from microalgae with a potential in industrial application.

Favored CH-π interaction between enzymatically modified high amylose starch and resveratrol improves digestion resistance

Starch-stilbene polyphenol complexes, a novel form of resistant starch (RS), have received considerable attention due to their potential health benefits. To enhance the functionality of this type of complex, we examined the interactions between resveratrol (RA) and high-amylose starch with different molecular weights, achieved through enzymatic modification followed by high-pressure homogenization (HPH). We examined how these interactions affect the digestibility and ordered structures of the complexes. Our findings reveal that, notwithstanding the inhibition of double helix and B-type crystalline structure formation, RA-starch complexation markedly boosted single helix content, V-type crystalline structure formation, and aggregate structure density. These effects contributed notably to increased RS content. Interestingly, the formation of the V6-type crystalline structure within the complexes was primarily facilitated by the CH-π interaction between the aromatic rings of RA and the C–H of starch, rather than conventional hydrogen bonding and electrostatic forces. The strength of the CH-π interaction increased with higher amylose content and lower molecular weight of the starch, achievable through a 12-h pullulanase hydrolysis followed by a 2-h α-amylase hydrolysis. The resulting HPH-Pα2-RA complexes exhibited remarkable levels of the V-type crystalline structure and RS content, reaching up to 25.45% and 57.37%, respectively. Overall, this study offers valuable insights into the design of starch-polyphenols complexes with a high RS content.

Amylopectin chain length distributions and amylose content are determinants of viscoelasticity and digestibility differences in mung bean starch and proso millet starch

This study aimed to reveal the underlying mechanisms of the differences in viscoelasticity and digestibility between mung bean starch (MBS) and proso millet starch (PMS) from the viewpoint of starch fine molecular structure. The contents of amylopectin B2 chains (14.94–15.09 %), amylopectin B3 chains (14.48–15.07 %) and amylose long chains (183.55–198.84) in MBS were significantly higher than PMS (10.45–10.76 %, 12.48–14.07 % and 70.59–88.03, respectively). MBS with higher amylose content (AC, 28.45–31.80 %) not only exhibited a lower weight-average molar mass (91,750.65–128,120.44 kDa) and R1047/1022 (1.1520–1.1904), but also was significantly lower than PMS in relative crystallinity (15.22–23.18 %, p < 0.05). MBS displayed a higher storage modulus (G′) and loss modulus (G′′) than PMS. Although only MBS-1 showed two distinct and discontinuous phases, MBS exhibited a higher resistant starch (RS) content than PMS (31.63–39.23 %), with MBS-3 having the highest RS content (56.15 %). Correlation analysis suggested that the amylopectin chain length distributions and AC played an important role in affecting the crystal structure, viscoelastic properties and in vitro starch digestibility of MBS and PMS. These results will provide a theoretical and scientific basis for the development of starch science and industrial production of low glycemic index starchy food.

Physicochemical, Quality and Flavor Characteristics of Starch Noodles with Auricularia cornea var. Li. Powder.

Auricularia cornea var. Li., as an edible mushroom rich in various nutrients, could be widely used in noodle food. This study aimed to investigate the effect of Auricularia cornea var. Li. (AU) powder on the gel properties, structure and quality of starch noodles. Taking the sample without adding AU powder as a control, the addition of AU powder enhanced the peak viscosity, trough viscosity, final viscosity, breakdown, setback, peak time, gelatinization temperature, G' (storage modulus) and G'' (loss modulus). Meanwhile, the incorporation of AU powder significantly enhanced the stability of the starch gel structure and contributed to a more ordered microstructure also promoting the short-term aging of starch paste. In vitro digestion results displayed lower rapid digestibility (21.68%) but higher resistant starch content (26.58%) with the addition of AU powder and increased breaking rate, cooking loss, swelling index and a* and b* values. However, it decreased dry matter content and L*, particularly the reducing sugar content significantly increased to 4.01% (p < 0.05), and the total amino acid content rose to 349.91 mg/g. The GC-IMS library identified 51 VOCs, and the OPLS-DA model classified 18 VOCs (VIP > 1). Overall, the findings indicate that starch noodles with the addition of AU powder may provide greater nutritional quality, gel stability and starch antidigestibility.

Unlocking the potential of sorghum: a comparative study exploring the physical, chemical, technological, and digestibility properties of new cultivars from Mozambique

SummaryThis study aimed to evaluate the physical, chemical, technological, and digestibility of three sorghum cultivars (Mucuvea, Otela, and Tocole) and compared them to a Local variety (criola) grown in Mozambique. Thousand‐grain weight, hectolitre weight, and colour were determined in the grains. Proximal composition, antinutritional factors, starch and protein digestibility, and antioxidant activity were analysed in flours; starch was isolated and characterised by its physical, chemical, morphological, and digestibility properties. The grain characterisation varied among the cultivars compared to the Local variety, but not between the cultivars. The cultivars showed lower amounts of protein, lipids, free phenolics, tannin, soluble protein, digestibility of starch flour and proteins, and higher flavonoids and antioxidant activity. A high content of amylose (~37%), glycaemic index (~82), Tp (64.83 °C), and resistant starch (57.73%) were verified in all cultivars. The peak viscosity of Local variety was higher (343.25 RVU) than the other cultivars, while the breakdown (less than 106.54 RVU) of the cultivars was significantly lower than Local (182.25 RVU). Such data suggest great potential use of Local variety in bakery products and the cultivars in products that require greater viscosity. These results will reinforce the research, production, and manufacture of new products in Africa, especially in sorghum‐producing countries.

Preparation of Multi‐Grain Flour with High Content of Resistant Starch and the Mechanism Underlying the Improved Digestion Resistance

AbstractTo acquire the optimum treatment strategy that leads to the highest yield of resistant starch (RS) in multigrain flour (MF), wheat flour, whole oat flour, and whole buckwheat flour are used to prepare antidigestive MF by using pullulanase debranching combining heat–moisture treatment (P‐HMT). Based on the single factor tests and response surface analysis, the optimum conditions for the treatment of MF are determined as follows: pullulanase 62.6 U g−1, autoclaving 21.3 min, HMT at 100 °C, and 30.4% water content for 6.0 h. Under these conditions, the yield of RS in the flour reaches 77.42%. P‐HMT causes protein denaturation, starch gelatinization, and flour clumps in MF, facilitating starch recrystallization and interactions among short‐chain starch, monomeric proteins, and lipids. All these findings are further confirmed by the conversion of starch crystal from A‐type to B+V‐type, the improvement of starch short‐range molecular order, and the presence of more binary/ternary complexes in treated flour. In brief, the starch digestion resistance improvement in the treated flour is attributed to the recrystallization of short‐chain starch and interactions between starch and protein/lipid.

Temporal changes in the fermentation characteristics, bacterial community structure and the functionality of the predicted metagenome of a batch fermenter medium containing the upper gastrointestinal enzyme resistant fraction of white sorghum (Sorghum bicolor L. Moench)

Sorghum is a potential prebiotic ascribed to the high native resistant starch (RS) content. Our previous studies on raw sorghum have revealed prominent amino acid fermentation despite the high RS content. Interestingly, autoclaved-freeze-dried sorghum fed rats exhibited beneficial microbial and biochemical profiles. Having a keen interest to reciprocally scrutinize the underlying mechanisms behind these contrasting outcomes, we used an in vitro porcine batch fermentation model. The fermentable substrates in raw and autoclaved-freeze-dried (three cycles) sorghum (AC) after in vitro gastrointestinal digestion fostered similar bacterial community structures, yet with significant differences in the characteristic amylolytic microbial taxa abundance and their temporal variation. Further, significant differences in the concentration of organic acids in raw and AC manifested the differences in the predicted abundance of the underlying pathways of carbohydrate and organic acid metabolism. Thus, this study highlights the propensity of the heat-moisture treatment of sorghum in modifying the fermentability of its RS.

In-Silico Identification, Characterization and Expression Analysis of Genes Involved in Resistant Starch Biosynthesis in Potato (Solanum tuberosum L.) Varieties.

Potato (Solanum tuberosum L.), an important horticultural crop is a member of the family Solanaceae and is mainly grown for consumption at global level. Starch, the principal component of tubers, is one of the significant elements for food and non-food-based applications. The genes associated with biosynthesis of starch have been investigated extensively over the last few decades. However, a complete regulation pathway of constituent of amylose and amylopectin are still not deeply explored. The current in-silico study of genes related to amylose and amylopectin synthesis and their genomic organization in potato is still lacking. In the current study, the nucleotide and amino acid arrangement in genome and twenty-two genes linked to starch biosynthesis pathway in potato were analysed. The genomic structure analysis was also performed to find out the structural pattern and phylogenetic relationship of genes. The genome mining and structure analysis identified ten specific motifs and phylogenetic analysis of starch biosynthesis genes divided them into three different clades on the basis of their functioning and phylogeny. Quantitative real-time PCR (qRT-PCR) of amylose biosynthesis pathway genes in three contrast genotypes revealed the down-gene expression that leads to identify potential cultivar for functional genomic approaches. These potential lines may help to achieve higher content of resistant starch.

High-resistant starch and low-glutelin content 1 rice benefits gut function in obese patients

The intestinal microbiota plays a crucial role in human health, yet the impact of high-resistant starch and low-glutelin rice in the gut of obese individuals remains unexplored. In this study, different types of rice, namely japonica rice (control), low-glutelin content 1 rice (Lgc1), high-resistant starch and low-glutelin content 1 rice (HR + Lgc1), and commercially available low-glycemic index rice (LowGI), were utilized as samples to examine their in vitro digestion and fermentation, as well as the impact of HR + Lgc1 on the intestinal microbiota in obese individuals. The findings revealed that HR + Lgc1 rice exhibited lower in vitro digestion rates for starch and protein compared to the other three types. Following 24 h of in vitro fermentation, the total short-chain fatty acid content in HR + Lgc1 was 108.67 mmol/L, which was 60.33, 51.26, and 17.29% that in control, Lgc1, and LowGI, respectively. Moreover, HR + Lgc1 rice displayed an inhibitory effect on the production of harmful branched-chain fatty acid metabolites. Analysis through 16S rDNA sequencing indicated that, after fermentation, HR + Lgc1 significantly enhanced the abundance of beneficial bacteria such as Bifidobacterium, Parabacteroides, and Faecalibacterium in the gut, whereas it reduced the abundance of harmful bacteria such as Escherichia-shigella. Our findings may contribute to the development of new foods rich in dietary fiber to improve the digestive function of patients with multiple comorbidities.

Exploring Scientific Validation of Millets in Contemporary Healthcare: A Traditional Food Supplement.

Millets, small-seeded grasses, are gaining interest for their nutrition and health benefits. This abstract provides a comprehensive overview of millets' pharmacological activities, highlighting their rich bioactive compounds. These compounds, including phenolic compounds, flavonoids, and dietary fibers, contribute to antioxidant effects, safeguarding against chronic diseases. Millets also possess anti-inflammatory properties, potentially alleviating conditions, like arthritis and asthma. They show anti-carcinogenic potential, possibly preventing various cancers' development through mechanisms, like apoptosis induction and inhibiting tumor growth. Moreover, millets offer hypolipidemic and hypoglycemic effects, beneficial for managing conditions, such as dyslipidemia and diabetes. Their high dietary fiber and resistant starch content regulate blood lipids and glucose, reducing the cardiovascular risk. Additionally, millets act as antimicrobials, inhibiting pathogens and serving as natural alternatives to synthetic antimicrobials. They exhibit immunomodulatory effects, enhancing immune function and response. Overall, millets' pharmacological properties, including antioxidant, antiinflammatory, anti-carcinogenic, hypolipidemic, hypoglycemic, antimicrobial, and immunomodulatory traits, position them as functional foods with varied health benefits. Further research can integrate millets into preventive and therapeutic approaches for diverse diseases.

Influence of enzymatic extraction on the properties of corn starch

Corn starch played an important role in the food industries, while traditional extraction method involved using sulfur dioxide that could easily cause environmental pollution and equipment corrosion. Based on these drawbacks, the main objective of this study was to develop a feasible two-step enzymatic extraction method that could isolate starch from corn kernels and evaluate the properties of corn starch. The physicochemical components of steep liquor during enzymatic extraction were researched, the single-factor experiments and response surface methodology were used to optimize the steeping conditions. As a result, optimized steeping parameters of which the first step time was 30 h, the lactic acid solution concentration was 0.45%, the protease content was 480 U/g, the l-cysteine content was 0.45 g, and the second step time was 4 h. The corn starch yield (65.18%) with enzymatic extraction was higher than that of traditional extraction (54.73%). The solubility and swelling power of all starch samples were raised with the temperature increasing. The starch extracted using the enzymatic method had a higher amylose content (35.18%) and mean diameter (30.99 μm). Compared with commercial corn starch, the starch samples presented nearly identical FT-IR spectra, the same A-type crystalline pattern and morphology, furthermore, a higher resistant starch content was detected in corn starch obtained through extraction methods. This finding will provide useful information to food industries for extraction of corn starch.

Changes in Cooking Characteristics, Structural Properties and Bioactive Components of Wheat Flour Noodles Partially Substituted with Whole-Grain Hulled Tartary Buckwheat Flour

The whole-grain, hulled Tartary buckwheat flour (HTBF) with outstanding bioactive functions was prepared, and the effects of partial substitution ratios (0, 30%, 51% and 70%) of wheat flour with HTBF on the characteristics of TB noodles (TBNs) were investigated, mainly including the cooking characteristics, sensory analysis, internal structure, bioactive components, and in vitro starch digestibility. With an increasing replacement level of HTBF, the water absorption index of the noodles decreased, whereas the cooking loss increased. A sensory analysis indicated that there were no off-flavors in all TBN samples. The scanning electron microscope images presented that the wheat noodles, 30% TBNs and 70% TBNs had dense and uniform cross sections. Meanwhile, the deepest color, V-type complexes, and lowest crystallinity (13.26%) could be observed in the 70% TBNs. A HTBF substitution increased the rutin content and the total phenolic and flavonoid contents in the TBNs, and higher values were found in the 70% TBNs. Furthermore, the lowest rapidly digestible starch content (16%) and highest resistant starch content (66%) were obtained in the 70% TBNs. Results demonstrated that HTBF could be successfully applied to make TBNs, and a 70% substitution level was suggested. This study provides consumers with a good option in the realm of special noodle-type products.

Effects of heat moisture treatment on the structure and digestibility of high amylose starch-lauric acid complexes

In this study, we investigated the effects of heat moisture treatment (HMT) on the structure and in vitro digestibility of high-amylose starch-lauric acid complexes, revealing the relationship between the effects of moisture content (MC) and fine structure in vitro digestibility of the complexes. The results showed that HMT changed the structure of the complexes, while MC significantly affected the resistant starch content, complex index, and relative crystallinity of the complexes. Compared with complexes without HMT, complexes prepared at 25% MC had the highest resistant starch content (63.97%), complex index (75.77%), and relative crystallinity (15.28%). The Fourier transform infrared spectroscopy results showed that the short-range order of the complexes was affected by the MC, particularly at 25% MC, which exhibited the highest short-range order among the complexes. Nuclear magnetic resonance spectroscopy results showed that the high amylose starch-lauric acid complexes prepared at an MC of 25% had a high V-shaped single-helix complex, which belonged to the V6-type crystalline structure. Small angle X-ray scattering data further indicated that complexes at this MC displayed a tighter structure with a larger lamellar thickness (dc) in the crystalline region. Therefore, we believe that the MC altered the fine structure of the complexes, which in turn affected their in vitro digestibility.

Synthesis of Pyrodextrins and Enzymatically Resistant Maltodextrins from Makal (Xanthosoma yucatenensis) Starch.

Enzymatically resistant maltodextrins (ERM) are a resistant starch type 4, synthesized from native starch. They are obtained by the sequential application of two processes: pyrodextrinization, which produces pyrodextrins, and enzymatic hydrolysis, which produces ERM. In these processes atypical bonds are formed that confer pyrodextrins and ERM similar properties to dietary fiber, such as resistance to digestion. The aim of this work is to determine and evaluate some physicochemical properties of pyrodextrins and ERM obtained from native starch isolated from makal (Xanthosoma yucatanense) tubers. Pyrodextrinization and complementary hydrolysis were conducted using factorial designs. For pyrodextrinization, factors and their levels were (m(starch):V(HCl))=80:1 and 160:1 (c(HCl)=2.2 M), temperature 90 and 110 °C and reaction time 1 and 3 h, and for CH, α-amylase per pyrodextrin volume fractions 0.5 and 1 µL/mL and reaction time 10 and 30 min. The physicochemical profile included determination of resistant starch content, estimation of color change (ΔE), microscopy and determination of dextrose equivalents (DE). According to the factorial design, the best treatment conditions for pyrodextrinization were: (m(starch):V(HCl))=160:1, 90 °C and 3 h, since they resulted in the highest resistant starch content (84.73 %) and the lowest ΔE (3.742). Due to the low DE (13.89 %), increased amount of resistant starch (90.73 %) and low ΔE (4.24) in the resulting ERM, complementary hydrolysis with α-amylase per pyrodextrin volume fraction 0.5 µL/mL and hydrolysis time 10 min was selected as the best treatment. The results show that the pyrodextrins and ERM obtained from makal can be used as ingredients for the development of functional foods, due to their high content of indigestible material and low degree of browning.

Physiochemical characterization and ameliorative effect of rice resistant starch modified by heat-stable α-amylase and glucoamylase on the gut microbial community in T2DM mice.

In the presented study, natural rice containing high resistant starch content was used as a raw material to produce rice resistant starch (RRS) through enzymatic hydrolysis with heat-stable α-amylase and glucoamylase. The chemical composition, structural characteristics and in vitro glycemic index (GI) of RRS were evaluated. The effects of RRS at different doses on the body weight, serum biochemical levels, pathological indexes, production of short-chain fatty acids (SCFAs) in the gut and the intestinal microbial composition in T2DM mice were investigated. The results of physiochemical characterization indicated that, relative to rice flour, RRS mainly comprising resistant starch had higher crystallinity (25.85%) and a more stable structure, which contributed to its lower digestibility and decreased GI in vitro. Compared with the model control group, 1 g per kg BW and 2 g per kg BW oral gavage dosages of RRS effectively enhanced the SCFA productivity in the T2DM mouse gut, as well as alleviating T2DM symptoms, involving an increase in body weight, reduction in fasting blood glucose, total cholesterol, triglyceride, low-density lipoprotein cholesterol, alanine transaminase and aspartate aminotransferase, and an increase in serum insulin and high-density lipoprotein cholesterol. Besides, 1 g per kg BW and 2 g per kg BW dosages of RRS mitigated T2DM-induced pancreas damage. Furthermore, up-regulation in the abundance of probiotics (Lactobacillus, Ruminococcus, etc.) and down-regulation in the number of harmful bacteria (Desulfovibrio, Prevotella, etc.) were observed in all RRS-treated groups. In summary, this work suggested that RRS prepared using heat-stable α-amylase and glucoamylase could be a potential functional component for amelioration of T2DM applied in the fields of food and pharmaceutics.

Stability of the Broiler Antibody Under Heat Stress Using Dry Rice

Stability of the Broiler Antibody Under Heat Stress Using Dry Rice