Effects of soluble dietary fibers on the viscosity property and digestion kinetics of corn starch digesta

Influence of mulberry, pectin, rutin, and their combinations on α-amylase activity and glucose absorption during starch digestion

Most studies have primarily focused on the effects of individual sources of pectin or polyphenols on starch digestibility. However, the interactions between pectin and polyphenols in digestive fluids may influence their inhibitory capacity against starch digestion by modulating α-amylase activity (αAA), a relationship that remains poorly understood. This study aims to clarify how pectin affects starch digestion when combined with mulberry fruit powder (MFP), mulberry polyphenol extract (MPE), and rutin (the main phenolic compound in MPE). Results showed that the combination of pectin and MFP initially inhibited αAA but later enhanced it. The combination of pectin and MPE consistently showed stronger inhibition of αAA than MPE alone throughout digestion; similar results were observed for the pectin-rutin combination, though the pectin-MPE pairing exhibited greater inhibition than the latter. Pectin's enhanced inhibitory effect on starch digestion may arise from its interactions with α-amylase, starch, and polyphenols through hydrophobic interactions, hydrogen bonding, and non-covalent forces.

Starch chain-length distributions affect the processing and digestion characteristics of proso millet starch

Starch chain-length distributions play a key role in regulating the processing and digestion characteristics of proso millet starch. Waxy proso millet starch has higher endothermic enthalpy (13.06-16.73 J/g) owing to its higher relative crystallinity (27.83%-32.04%), while nonwaxy proso millet starch has lower peak viscosity (1.0630-1.1930 Pa∙s) and stronger viscoelasticity owing to its higher amylose content (21.72%-24.34%). Non-waxy proso millet starch exhibited two different digestion phases and its resistant starch content (18.37%-20.80%) was higher than waxy proso millet starch. Correlation analysis showed proso millet starch with longer amylopectin B1 chains and more amylopectin B2 chains exhibited excellent thermal ability and retrograde resistance, whereas proso millet starch with shorter and more amylose medium/long-chains not only reduced the digestion rate and increased the resistant starch content but also exhibited stronger viscoelasticity and excellent retrogradation properties. These results could provide more insights into efficient utilization of proso millet starch.

Dietary fiber-rich Lentinula edodes stems influence the structure and in vitro digestibility of low-moisture extruded maize starches

Low-moisture extrusion (LME) can be used to improve the utilization of dietary fiber-rich Lentinula edodes stems (LES). The incorporation of dietary fiber can affect heat-induced interactions of starch molecules, which are critical for modifying starch characteristics via LME. In this work, a blend of LES and maize starch was extruded into a product at low moisture (30 %, w/v). The structure, physicochemical properties, and in vitro digestibility of extruded maize starches were investigated at different LES levels. The results showed that low levels (<7 %) of LES increased the crystallinity of LME-produced starch, while high levels (>7 %) did not. Because of the LES's soluble to insoluble dietary fiber ratios, the increased crystallinity of LES-added starch led to greater molecular ordering and the formation of an elastic gel after LME. At a suitable LES level (~3 %), highly crystallized starches were resistant to enzymolysis and had a high proportion of resistant starch. The obtained findings would contribute to a better understanding of how dietary fiber-rich LES affects starch extrusion and provide an alternative use for boosting the value of LES by-products.

A review of healthy role of dietary fiber in modulating chronic diseases

Dietary fiber (DF) is considered an interventional diet beneficial for human health. High DF intake effectively reduces the incidence of three major chronic diseases, type 2 diabetes (T2DM), cardiovascular disease (CVD), and colorectal cancer (CRC). The health benefits of DF are closely related to their physicochemical properties with major positive roles in human digestion and intestinal health. However, mechanisms linking DF with diseases remain unclear. The development of genomics, metabolomics, and immunology, and the powerful combination of animal models and clinical trials, have facilitated a better understanding of the relationships between DF and diseases. Accumulating evidence suggests that the physical existence of DF and DF-microbiota interaction are the key parameters controlling the action mechanisms of DF in chronic diseases. Therefore, this review discusses the potential mechanism of DF modulating T2DM, CVD, and CRC, therefore providing a theoretical basis for more effective use of DF to intervene in chronic diseases.

Enhancing optimal molecular interactions during food processing to design starch key structures for regulating quality and nutrition of starch-based foods: an overview from a synergistic regulatory perspective

Charting out personalized and/or optimized diets offers new opportunities in the field of food science, although with inherent challenges. Starch-based foods are a major component of daily energy intake in humans. In addition to being rich in starch, starchy foods also contain a multitude of bioactive substances (e.g., polyphenols, lipids). Food processing including storage affects the consistency and interactions between starch and other food components, which can affect the quality and nutritional characteristics of starch-based foods. This review describes the effects of interactions between starch and other components on the structural evolution of starch during food processing. We ponder upon how the evolution of starch molecular structure affects the quality and nutritional characteristics of starch-based foods vis-a-vis the structure-property relationship. Furthermore, we formulate best practices in processing starchy food to retain the quality and nutritional value by rationally designing starch structural domains. Interestingly, we found that inhibiting the formation of a crystalline structures while promoting the formation of short-range ordered structures and nano-aggregates can synchronously slow down its digestion and retrogradation properties, thus improving the quality and nutritional characteristics of starch-based food. This review provides theoretical guidelines for new researchers and food innovators of starch-based foods.

Combined dilute alkali and milling process enhances the functionality and gut microbiota fermentability of insoluble corn fiber

In this study, we developed a process combining dilute alkali (NaOH or NaHCO3) and physical (disk milling and/or ball milling) treatments to improve the functionality and fermentability of corn fiber. The results showed that combining chemical with physical processes greatly improved the functionality and fermentability of corn fiber. Corn fiber treated with NaOH followed by disk milling (NaOH-DM-CF) had the highest water retention (19.5 g/g), water swelling (38.8 mL/g), and oil holding (15.5 g/g) capacities. Moreover, NaOH-DM-CF produced the largest amount (42.9 mM) of short-chain fatty acid (SCFA) during the 24-hr in vitro fermentation using porcine fecal inoculum. In addition, in vitro fermentation of NaOH-DM-CF led to a targeted microbial shifting to Prevotella (genus level), aligning with a higher fraction of propionic acid. The outstanding functionality and fermentability of NaOH-DM-CF were attributed to its thin and loose structure, decreased ester linkages and acetyl groups, and enriched structural carbohydrate exposure.

Effects of soluble dietary fiber from pomegranate peel on the physicochemical properties and in-vitro digestibility of sweet potato starch

The effects of soluble dietary fiber (SDF) from pomegranate peel obtained through enzyme (E-SDF) and alkali (A-SDF) extractions on the structural, physicochemical properties, and in vitro digestibility of sweet potato starch (SPS) were investigated. The expansion degree of SPS granules, pasting viscosity, gel strength and hardness were decreased after adding E-SDF. The setback was accelerated in the presence of A-SDF but E-SDF delayed this effect during the cooling of the starch paste. However, the addition of A-SDF significantly reduced the breakdown of SPS and improved the freeze-thaw stability of starch gels, even at low concentrations (0.1 %), while E-SDF showed the opposite result. The structural characterization of SDF-SPS mixtures showed that A-SDF can help SPS form an enhanced microstructure compared with E-SDF, while polar groups such as hydroxyl group in E-SDF may bind to leached amylose through hydrogen bonding, leading to a decrease in SPS viscoelasticity. In addition, the results of in vitro digestion analysis indicated that A-SDF and E-SDF could decreased the digestibility of SPS and increased the content of resistant starch, especially when 0.5 % E-SDF was added. This study provides a new perspective on the application of SDF from pomegranate peel in improving starch-based foods processing and nutritional characteristics.

Relationship between microstructure formation and in vitro starch digestibility in baked gluten-starch matrices

Increased prevalence of diabetes prompts the development of foods with reduced starch digestibility. This study analyzed the impact of adding soluble dietary fiber (inulin-IN; polydextrose-PD) to baked gluten-starch matrices (7.5-13%) on microstructure formation and in vitro starch digestibility. IN and PD enhanced water-holding capacity, the hardness of baked matrices, and lowered water activity in the formulated matrices, potentially explaining the reduced starch gelatinization degree as IN or PD concentration increased. A maximum gelatinization decrease (26%) occurred in formulations with 13% IN. Micro-CT analysis showed a reduction in total and open porosity, which, along with the lower gelatinization degree, may account for the reduced in vitro starch digestibility. Samples with 13% IN exhibited a significantly lower rapidly available glucose fraction (8.56 g/100 g) and higher unavailable glucose fraction (87.76 g/100 g) compared to the control (34.85 g/100 g and 47.59 g/100 g, respectively). These findings suggest the potential for developing healthier, starch-rich baked foods with a reduced glycemic impact.

Effect of hydrocolloids on starch digestion: A review

Rapidly digestible starch can increase postprandial blood sugar rapidly, which can be overcome by hydrocolloids. The paper aims to review the effect of hydrocolloids on starch digestion. Hydrocolloids used to reduce starch digestibility are mostly polysaccharides like xanthan gum, pectin, β-glucan, and konjac glucomannan. Their effectiveness is related to their source and structure, mixing mode of hydrocolloid/starch, physical treatment, and starch processing. The mechanisms of hydrocolloid action include increased system viscosity, inhibition of enzymatic activity, and reduced starch accessibility to enzymes. Reduced starch accessibility to enzymes involves physical barrier and structural orderliness. In the future, physical treatments and intensity used for stabilizing hydrocolloid/starch complex, risks associated with different doses of hydrocolloids, and the development of related clinical trials should be focused on. Besides, investigating the effect of hydrocolloids on starch should be conducted in the context of practical commercial applications rather than limited to the laboratory level.

The ileal, total tract and postileal digestibility of compound feeds either rich in wheat or rye in an ileo-caecal fistulated minipig model

Environmental issues and concerns about animal welfare display current challenges in animal husbandry and feeding. Rye, a cereal that has scarcely been used in animal feed in recent decades, could help address some of the challenges in pig feeding as a climate friendly and health promoting feed ingredient. Distinct constituents of rye - especially its non-starch-polysaccharides (NSP) - are fermented in the large intestine while short chain fatty acids (SCFA) are produced in that process. This can promote gut health and the feeling of satiety in pigs. To examine the site of the digestion of rye within the digestive tract in comparison to wheat as a widely used ingredient in pig diets, two diets with high shares of either wheat or rye (each 69.0%) were fed to ileo-caecally fistulated, adult minipigs. Ileal digesta and faeces were collected and ileal, total tract and postileal digestibility rates were calculated. In the apparent ileal digestibility (AID), significant differences were only found for organic matter (OM) and Nitrogen-free extract (NfE) with lower values for the rye-rich diets (77.2 ± 2.00 vs. 73.8 ± 2.01% and 79.8 ± 2.56 vs. 75.3 ± 2.61%, respectively). These differences could not be recovered for the total tract digestibility (ATTD - 90.2 ± 2.16 vs. 89.8 ± 1.94% and 93.0 ± 1.69 vs. 92.8 ± 1.37%, respectively), resulting in an elevated postileal digestibility which was significant for NfE (13.2 ± 2.42 vs. 17.5 ± 2.77%). Therefore, rye can be used to promote hindgut fill and fermentation in pig feeding, especially in restrictively fed animals such as pregnant sows.

Interactions of hsian-tsao polysaccharide with corn starch to reduce its in vitro digestibility

Hsian-tsao polysaccharide (HP) with preferable bioactivities was used to produce starchy gel foods. This study elucidated how interactions of HP (0-0.6 %, w/v) with gelatinized corn starch (CS, 6 %, w/v) reduced in vitro digestibility of CS. The CS digestibility (82.85 %, without HP) was reduced to 68.85 % (co-heated) and 74.75 % (non-co-heated) when 0.6 % HP was added, demonstrating that HP reduced the CS digestibility to a larger extent under co-heating by both HP-CS interactions and inhibiting digestive enzyme activities by HP which was dominated under non-co-heating. Moreover, when co-heated, HP bonded to the amylose of CS via physical forces with a composite index of 21.95 % (0.4 % HP), impeded CS swelling and promoted CS aggregation with the average particle size increased to 42.95 μm (0.6 % HP). Also, the HP-CS complexes formed strong association network structures that increased their apparent viscosity and digestive fluid viscosity. Additionally, HP enhanced the short-range ordered structure and crystal structure of CS. These results evidenced that HP-CS interactions significantly reduced the CS digestibility by forming physical barriers, viscosity effects, and ordered structures, to hinder the enzymes from accessing starch matrices. This laid a foundation for applying HP to starchy foods with a low predicted glycemic index.

Psyllium Fibre Inclusion in Gluten-Free Buckwheat Dough Improves Dough Structure and Lowers Glycaemic Index of the Resulting Bread

The demand for gluten-free (GF) bread is steadily increasing. However, the production of GF bread with improved baking quality and enhanced nutritional properties remains a challenge. In this study, we investigated the effects of adding psyllium fibre (PSY) in varying proportions to buckwheat flour on the dough characteristics, bread quality, and starch digestion properties of GF bread. Our results demonstrate that incorporating PSY contributes to the formation of a gluten-like network structure in the dough, leading to an increase in the gas holding capacity from 83.67% to 98.50%. The addition of PSY significantly increased the specific volume of the bread from 1.17 mL/g to 3.16 mL/g. Bread containing PSY displayed superior textural characteristics and colour. Our study also revealed that the inclusion of PSY reduced the digestibility of starch in GF bread. These findings highlight the positive impact of incorporating PSY into GF bread, suggesting its potential in guiding the production of GF bread with a lower glycaemic index. This may be particularly beneficial for individuals seeking to regulate their blood sugar levels or adopt a low-glycaemic diet.

Physicochemical, thermal, pasting, morphological, functional and bioactive binding characteristics of starches of different oat varieties of North-Western Himalayas

Starches were isolated from five oat varieties (SFO-1, SFO-3, Sabzar, SKO-20 and SKO-96) grown in North-Western Himalayas of India. Moisture content of the varieties ranged from 9.25 ± 0.09 to 13.21 ± 0.11 %, indicating their shelf-stability. Results suggested >90 % purity of starches as was evident from values of ash, proteins, and lipids. Amylose content results showed that all starches fall within category of intermediate-amylose starches. Lambdamax, blue value and OD620/550 were found significantly (p ≤ 0.05) higher in SKO-20. Sabzar exhibited higher starch hydrolysis percentage of 85.16 % whereas, lowest was observed in SKO-20 (78.12 %). Degree of syneresis was higher in SKO-20 however, its freeze-thaw stability was lesser. Wide peak in FTIR spectra at 3320 cm-1 confirms nature of starches. SKO-20 exhibited significantly higher onset gelatinization temperature (65.19 ± 1.06 °C) and enthalpy (15.78 ± 0.15 J/g) whereas, Sabzar exhibited lowest enthalpy. Pasting characteristics indicated lowest and highest final viscosity in SKO-20 (341.30 ± 2.11 mPas) and SKO-96 (1470 ± 4.56 mPas), respectively. SEM results indicated irregular and polygonal shape of starches with size <10 μm. SKO-20 exhibited lowest disintegration time of 2.08 ± 0.01 min and Sabzar showed highest (3.31 ± 0.07 min). SKO-20 released more curcumin (71.28 %) whereas, Sabzar released less. This suggests that SKO-20 could be used as better excipient for delivery of curcumin at target site.

Comparison of quinoa and highland barley derived dietary fibers influence on the physicochemical properties and digestion of rice starch

This study investigated the potential of highland barley and quinoa dietary fibers, rich in β-glucan and pectin respectively, as cost-effective and nutritionally valuable physical modifiers for rice starch (RS). HPAEC revealed differences between the monosaccharide composition of soluble and insoluble dietary fibers sourced from highland barley and quinoa (HSDF, HIDF, QSDF and QIDF). Results from both RVA and DSC analysis revealed that the addition of low amounts of dietary fiber significantly modified the pasting properties of RS. Notably, the addition of quinoa soluble dietary fiber (QSDF) significantly inhibits the formation of a stable gel network in rice starch, even at low concentrations (0.1 %), as confirmed by rheological measurements. Furthermore, the incorporation of QSDF effectively reduces the content of rapidly digestible starch in rice starch by 15.6 % and increases the content of slowly digestible starch, from 23.36 % ± 3.02 % to 31.07 % ± 3.98 %. By leveraging the compositional richness of these fibers, this research opens up novel opportunities for developing functional food products with improved nutritional profiles, as well as for improving texture and reducing glycemic index (GI) in starch-based foods.

Recent progress in regulating starch digestibility using natural additives and sustainable processing operations

The development of a healthier and more sustainable food supply is a main concern of consumers, industry, governments, and international institutions. Foods containing high levels of rapidly digestible starches have been linked to a rise in the number of people suffering from diet-related chronic diseases. Consequently, there is interest in reducing the digestibility of starch to improve their healthiness. The ability of natural additives including proteins, dietary fibers, and polyphenols, and sustainable processing technologies such as high-intensity ultrasonic, pulsed electric field, non-thermal plasma, γ-ray irradiation that regulate reduce starch digestibility in foods are reviewed. The potential mechanisms of action, advantages, and disadvantages of each approach at inhibiting starch digestibility is highlighted. The potential for commercializing these technologies is discussed, and areas where further research are required are emphasized. Natural additives and sustainable processing operations can effectively reduce the digestibility of starch and inhibit postprandial sugar "spikes" in the bloodstream by adjusting the structural changes, which can be used to create healthier and more sustainable foods and have broad application prospects.

Comparison and the lipid-lowering ability evaluation method discussion of Dendrobium officinale polysaccharides from different origins based on principal component analysis

As typical acetylated glucomannans, Dendrobium officinale polysaccharides (DOPs) from different origins differ in their structural characteristics and some of their physicochemical properties. To rapidly select D. officinale plants, we systematically investigate the differences among DOPs from different origins and analyzed the structural characteristics, such as the degree of acetylation and monosaccharide composition; the physicochemical properties, such as solubility, water absorption and apparent viscosity; and the lipid-lowering activity of the obtained DOPs. Principal component analysis (PCA), a method for analyzing multiple variables, was used to analyze the relationship between the physicochemical and structural properties, and lipid-lowering activity. It was found that the structural and physicochemical characteristics had significant effects on lipid-lowering activity, and DOPs with a high degree of acetylation, high apparent viscosity and large D-mannose-to-d-glucose ratio were associated with greater lipid-lowering activity. Therefore, this study provides a reference for the selection and application of D. officinale.

Effects of hawthorn addition on the physicochemical properties and hydrolysis of corn starch

Hawthorn powder were mixed with corn starch and heated in water to make corn starch-hawthorn mixtures (CS-Haw) and then the physicochemical properties and hydrolysis characteristics of the mixtures were measured. Results showed that the addition of hawthorn powder decreased the viscosity of corn starch, and prolonged the pasting temperature, while the microstructure analysis indicated that hawthorn particles aggregated on the surfaces of starch granules, reducing the chance of starch contacting with water, then delayed the starch gelatinization. The presence of hawthorn powder also reduced the G' value to varying degrees and the loss tangent of CS-Haw was significantly higher than that of corn starch. The addition of hawthorn powder in large amounts also increased the rapidly digestible starch, while decrease the slowly digestible starch and resistant starch. The present research will provide basic theoretical support for the application of hawthorn in healthy starch food processing.

Enrichment of Wholemeal Rye Bread with Plant Sterols: Rheological Analysis, Optimization of the Production, Nutritional Profile and Starch Digestibility

Bread is one of the staple foods of many countries, and its enrichment with bioactive compounds is trending. This phenomenon is focused on breads with a good nutritional profile, such as wholemeal rye bread (WRB), in which enrichment with plant sterols (PSs) is allowed in accordance with European regulations. The objective of the present study was to optimize the production of a WRB enriched with PS (PS-WRB) and to evaluate the proximate composition and starch digestibility as an indicator of nutritional quality. The rheological analysis showed that the bread dough presents satisfactory farinographic properties (dough development time 6 min; stability 4 min; degree of softening 100 Brabender units) but high water absorption (67%). The PS-WRB is high in dietary fiber and low in protein (20.4 and 7.7% w/w, dry basis, respectively) compared with other cereals reported in the scientific literature. In turn, a low starch proportion was hydrolyzed during the simulated digestion (59.9% of total starch), being also slowly hydrolyzed, as deduced from the rapidly digestible starch value (56.5% of total starch). In conclusion, WRB is a suitable matrix for PS enrichment, which allows for obtaining a product with a good nutritional profile and potential health benefits.

Sheep Milk Symbiotic Ice Cream: Effect of Inulin and Apple Fiber on the Survival of Five Probiotic Bacterial Strains during Simulated In Vitro Digestion Conditions

We conducted a study to determine the survival of bacterial cells under in vitro digestion. For this purpose, ice cream mixes were prepared: control, with 4% inulin, 2.5% inulin and 1.5% apple fiber and 4% apple fiber. Each inoculum (pH = 4.60 ± 0.05), containing 9 log cfu g^-1 bacteria, at 5% (w/w) was added to the ice cream mixes (Lacticaseibacilluscasei 431, Lactobacillus acidophilus LA-5, Lacticaseibacillus paracasei L-26, Lacticaseibacillusrhamnosus, Bifidobacterium animalis ssp. lactis BB-12) and fermentation was carried out to pH 4.60 ± 0.05. The in vitro digestion method simulated the stages of digestion that occur in the mouth, stomach and small intestine under optimal controlled conditions (pH value, time and temperature). At each stage of digestion, the survival rate of probiotic bacteria was determined using the plate-deep method. As expected, in the oral stage, there was no significant reduction in the viability of the probiotic bacteria in any ice cream group compared to their content before digestion. In the stomach stage, Bifidobacterium animalis ssp. lactis BB-12 strain had the highest viable counts (8.48 log cfu g^-1) among the control samples. Furthermore, a 4% addition of inulin to ice cream with Bifidobacterium BB-12 increased gastric juice tolerance and limited strain reduction by only 16.7% compared to the number of bacterial cells before digestion. Regarding ice cream samples with Bifidobacterium BB-12, replacing part of the inulin with apple fiber resulted in increased survival at the stomach stage and a low reduction in the bacterial population of only 15.6% compared to samples before digestion. At the stomach stage, the positive effect of the addition of inulin and apple fiber was also demonstrated for ice cream samples with Lacticaseibacilluscasei 431 (9.47 log cfu g^-1), Lactobacillus acidophilus LA-5 (8.06 log cfu g^-1) and Lacticaseibacillus paracasei L-26 (5.79 log cfu g^-1). This study showed the highest sensitivity to simulated gastric stress for ice cream samples with Lacticaseibacillusrhamnosus (4.54 log cfu g^-1). Our study confirmed that the 4% addition of inulin to ice cream increases the survival rate of L. casei and Bifidobacterium BB-12 in simulated intestinal juice with bile by 0.87 and 2.26 log cfu g^-1, respectively. The highest viable count in the small intestine stage was observed in ice cream with L. acidophilus. The addition of inulin increased the survival of L. rhamnosus by 10.8% and Bifidobacterium BB-12 by about 22% under conditions of simulated in vitro digestion compared to their control samples. The survival rates of L. casei and L. paracasei were also highly affected by the 4% addition of apple fiber, where the increase under gastrointestinal passage conditions was determined to range from 7.86-11.26% compared to their control counterparts. In comparison, the lowest survival rate was found in the control ice cream with L. rhamnosus (47.40%). In our study at the intestinal stage, only five ice cream groups: a sample with 4% inulin and L. acidophilus, a control sample with Bifidobacterium BB12, a sample with 2.5% inulin and 1.5% apple fiber with Bifidobacterium BB12, a control sample with L. rhamnosus, a sample with 4% fiber and L. rhamnosus reported bacterial cell counts below 6 log cfu g^-1 but higher than 5 log cfu g^-1. However, in the remaining ice cream groups, viable counts of bacterial cells ranged from 6.11 to 8.88 log cfu g^-1, ensuring a therapeutic effect. Studies have clearly indicated that sheep milk ice cream could provide a suitable matrix for the delivery of probiotics and prebiotics and contribute to intestinal homeostasis. The obtained results have an applicative character and may play an essential role in developing new functional sheep milk ice cream.

Effects of psyllium fiber on in vitro digestion and structure of different types of starches

BACKGROUND

Starch digestibility in foods strongly depends on the structure, other ingredients and processing conditions used. This study aimed to investigate the effect of psyllium fiber on gelatinization, crystallinity and in vitro digestibility of starches having different crystalline structures (A, B and C). Wheat, potato and tapioca starches with and without added psyllium fiber were heated at 90 °C for 10 min at three different solid:water (w:v) ratios (1:1, 1:2 and 1:5). The added fiber content was 50% (dry base) in the solid fraction for the fiber-added samples.

RESULTS

Wheat, potato and tapioca starches showed different structural, morphological and starch digestibility properties. The effect of cooking and fiber addition on starch digestion differed for the starch types, mainly wheat starch. Psyllium addition during cooking decreased the rapidly digestible starch (RDS) fractions while increasing the slowly digestible starch (SDS) and remaining/resistant starch (RS) fractions. The effect of psyllium fiber addition was not limited to restricting the swelling and gelatinization of starch granules during heating. Psyllium fiber effectively restricted the mobility of digestive enzymes during digestion.

CONCLUSION

Understanding the relationship between psyllium and starch digestibility for different types of starch could assist in designing food formulations with lower starch digestibility. These in vitro data, however, should be confirmed by in vivo studies. © 2021 Society of Chemical Industry.