Slow Digestion Research Articles

Unveiling the slow digestion and peptide profiles of polymerised whey gel via heat and TGase crosslinking: An in vitro/vivo perspective

Polymerised whey is widely used in dairy products and can affect digestibility when its high-molecular-weight aggregates and gel structure are modified. This study investigated the digestibility, peptide profiles and satiety of modified whey protein isolate (MWPI) pre-heated with transglutaminase. Results showed that 43.06 % of MWPI was digested during the 4-h in vitro digestion, indicating a slow digestion rate. Compared with whey protein isolate (WPI), MWPI yielded 103 peptides with higher abundance following in vitro digestion, including 17 angiotensin-converting enzyme inhibitors and 1 dipeptidyl peptidase-4 inhibitor. Visual analytics indicated differential peptides located at distinct α-helix and β-sheet of β-lactoglobulin, α-lactalbumin and bovine serum albumin. MWPI gavage extended stomach retention time, decreased intestinal propulsion rate from 75.60 % (WPI group) to 33.72 % in 30 min and enhanced satiety within 120 min compared with WPI. Overall, whey polymerisation modulates protein–enzyme interactions, releasing different peptides and enhancing satiety.

Elucidation of the noncovalent interactions driving enzyme activity guides branching enzyme engineering for α-glucan modification

Branching enzymes (BEs) confer to α-glucans, the primary energy-storage reservoir in nature, a variety of features, like slow digestion. The full catalytic cycle of BEs can be divided in six steps, namely two covalent catalytic steps involving glycosylation and transglycosylation, and four noncatalytic steps involving substrate binding and transfers (SBTs). Despite the ever-growing wealth of biochemical and structural information on BEs, clear mechanistic insights into SBTs from an industrial-performance perspective are still missing. Here, we report a Rhodothermus profundi BE (RpBE) endowed with twice as much enzymatic activity as the Rhodothermus obamensis BE currently used in industry. Furthermore, we focus on the SBTs for RpBE by means of large-scale computations supported by experiment. Engineering of the crucial positions responsible for the initial substrate-binding step improves enzymatic activity significantly, while offering a possibility to customize product types. In addition, we show that the high-efficiency substrate-transfer steps preceding glycosylation and transglycosylation are the main reason for the remarkable enzymatic activity of RpBE, suggestive of engineering directions for the BE family.

Texture, swallowing and digestibility characteristics of a low-GI dysphagia food as affected by addition of dietary fiber and anthocyanins

Dysphagia is a common problem in the elderly population, thus texture modifications in foods suitable for dysphagic patients aroused a lot of interest. In the study, low glycemic index (GI) dysphagia foods were designed with adding dietary fiber (DF) and anthocyanins (AS), and their in vitro enzymatic digestion and predicted GI values were investigated by first-order kinetic model and slope log model. Results showed that all samples belonged to dysphagia foods at level 4 (pureed) in the International Dysphagia Diet Standardization Initiative (IDDSI) framework, and exhibited shear thinning behavior. AS reduced the apparent viscosity and storage modulus, increased redness, while DF decreased the hardness and gumminess of dysphagia food masses. DF and AS significantly increased the slowly digestible starch and resistant starch content in food system. With the increased addition of 5 % DF and 3 % AS, the predicted GI value of dysphagia food masses could be decreased to 51.08 ± 2.48, which belonged to the low-GI food, and showed the best water holding capacity and the highest total sensory evaluation score. In addition, a strong correlation was also found between the slow digestion indicators, rheological properties and swallowing ease. This study provides a theoretical foundation for the design of dysphagia food products with slow digestibility and low GI values.

Effect of Polygonatum cyrtonema Hua polysaccharides on gluten structure, in vitro digestion and shelf-life of fresh wet noodle

This study aimed to investigate the effects of raw Polygonatum cyrtonema Hua polysaccharides (RPCPs) and “zhi” P. cyrtonema Hua polysaccharides (ZPCPs) on the gluten structure, in vitro digestion, and shelf life of fresh wet noodles (FWN). The results demonstrated that incorporating PCPs improved the cooking and sensory qualities of FWN. Moreover, the shelf life of FWN was extended by 6 days with 1.5 % RPCPs (w/w) compared with the control FWN. Furthermore, incorporating 1.5 % ZPCPs led to a 1.2- and 0.2-fold increase in the disulfide bond and α-helix content, respectively, compared with the control FWN. This resulted in enhanced gluten structure, improved springiness and viscidity, and reduced cooking loss by 14.47 %–52.19 %. The scanning electron microscopy analysis revealed that the starch particles were entrapped by PCPs, leading to higher gelatinization temperature and lower setback value of FWN, thereby reducing the starch digestion ratio to 55.50 %. In summary, the findings suggested that FWN containing PCPs can extend shelf life, improve taste, and slow starch digestion staple.

Highly Soluble β-Glucan Fiber Modulates Mechanisms of Blood Glucose Regulation and Intestinal Permeability.

β-glucans found in cereal grains have been previously demonstrated to improve blood glucose control; however, current understanding points to their high viscosity as the primary mechanism of action. In this work, we present a novel, highly soluble, low-viscosity β-glucan fiber (HS-BG fiber) and a preclinical dataset that demonstrates its impact on two mechanisms related to the prevention of hyperglycemia. Our results show that HS-BG inhibits the activity of two key proteins involved in glucose metabolism, the α-glucosidase enzyme and the SGLT1 transporter, thereby having the potential to slow starch digestion and subsequent glucose uptake. Furthermore, we demonstrate in a multi-donor fecal fermentation model that HS-BG is metabolized by several different members of the gut microbiome, producing high amounts of short-chain fatty acids (SCFAs), known agonists of GPR43 receptors in the gut related to GLP-1 secretion. The production of SCFAs was verified in the translational gut model, SHIME®. Moreover, HS-BG fiber fermentation produces compounds that restored permeability in disrupted epithelial cells, decreased inflammatory chemokines (CXCL10, MCP-1, and IL-8), and increased anti-inflammatory marker (IL-10), which could improve insulin resistance. Together, these data suggest that the novel HS-BG fiber is a promising new functional ingredient that can be used to modulate postprandial glycemic responses while the high solubility and low viscosity enable easy formulation in both beverage and solid food matrices.

Advances in Extraction, Structure, and Physiochemical Properties of Sorghum Kafirin for Biomaterial Applications: A Review.

Kafirin is an endosperm-specific hydrophobic protein found in sorghum grain and the waste by-product from sorghum biorefineries known as sorghum dried distillers' grain with solubles (DDGS). Because of kafirin's poor nutritional profile (negative nitrogen balance, slow digestibility, and lack of some essential amino acids), its direct human use as a food is restricted. Nevertheless, increased focus on biofuel production from sorghum grain has triggered a new wave of research to use sorghum DDGS kafirin as a food-grade protein for biomaterials with diverse applications. These applications result from kafirin's unique chemical nature: high hydrophobicity, evaporation-induced self-assembling capacity, elongated conformation, water insolubility, and low digestibility. Aqueous alcohol mixtures have been widely used for the extraction of kafirin. The composition, structure, extraction methodologies, and physiochemical properties of kafirin, emphasising its biomaterial functionality, are discussed in detail in this review. The literature survey reveals an in-depth understanding of extraction methodologies and their impact on structure functionality, which could assist in formulating materials of kafirin at a commercial scale. Ongoing research continues to explore the potential of kafirin and optimise its utilisation as a functional biomaterial, highlighting its valuable structural and physicochemical properties. Further studies should focus on covering gaps in the research as some of the current structural understanding comes from data on zein protein from maize.

Improving resistant starch content of cassava starch by pulsed electric field-assisted esterification

This study aims to investigate the effect of pulsed electric field (PEF) assisted OSA esterification treatment on the multi-scale structure and digestive properties of cassava starch and structure-digestion relationships. The degree of substitution (DS) of starch dually modified at 1.5–4.5 kV/cm was 37.6–55.3 % higher than that of starch modified by the conventional method. Compared with native starch, the resistant starch (RS) content of esterified starch treated with 3 kV/cm significantly increased by 17.13 %, whereas that of starch produced by the conventional method increased by only 5.91 %. Furthermore, assisted esterification at low electric fields (1.5–3 kV/cm) promotes ester carbonyl grafting on the surface of starch granules, increases steric hindrance and promotes the rearrangement of the amorphous regions of starch, which increases the density of the double-helical structure. These structural changes slow down starch digestion and increase the RS content. Therefore, this study presents a potential method for increasing the RS content of starch products using PEF to achieve the desired digestibility.

Multi-scale structural insights on starch digestibility of instant rice

Multi-scale structures were investigated to understand starch digestibility of instant rice. A wide range of maximum starch digested ratio, up to about 20%, was observed among instant rice prepared from different rice varieties. Instant rice with a smooth and densely packed cross-section showed slower starch digestibility than those with a porous and loosely packed structure. All samples displayed B + V type crystallinity, with V-type crystallinity negatively correlating with maximum starch digested percentage. After digestion, starch chain-length distributions were significantly altered: rapidly digested starch comprised long amylose and short amylopectin chains, while slowly digested starch comprised chains with a peak degree of polymerization (DP) around 130. These results indicate that instant rice with a compact microstructure, high V-type crystallinity, and DP 130 fractions during digestion can reduce starch digestibility. This study provides insights for food industry to develop instant rice products with slow starch digestibility, potentially improving human health.

Application of supercritical carbon dioxide to enhance the aroma of whole sorghum flour for use in 3D printing of sorghum cookies

Sorghum is a promising ingredient for new food products due to its high fiber content, slow digestibility, drought resistance, and gluten-free nature. One of the main challenges in sorghum-based products is the unpleasant aroma compounds found in grain sorghum. Therefore, in this study, sorghum flour was treated via supercritical carbon dioxide (SC-CO2) to remove undesired aroma compounds. The resulting SC-CO2-treated flours were used to generate dough for 3D food printing. At the optimized conditions, sorghum cookies were 3D-printed using 60 % water and a nozzle diameter of 1.5 mm. All dough samples produced with untreated and SC-CO2-treated sorghum flours exhibited shear-thinning behavior. Changing the treatment pressure (8–15 MPa) or temperature (40–60 °C) did not significantly affect the viscosity of the dough samples. Moreover, the sorghum cookie doughs had higher G′ and G″ values after the SC-CO2 treatments (G′ >G″). Doughs generated from flours treated at 15 MPa − 40 °C and 8 MPa − 60 °C showed lower adhesiveness compared to the ones produced from untreated flour, whereas 15 MPa − 60 °C treatment did not affect the adhesiveness. After baking, the 3D-printed cookies from SC-CO2-treated flour exhibited significantly lower redness (a*), but the hardness of the cookies was not affected by SC-CO2 treatment. Overall, the SC-CO2 treatment of sorghum flour did not negatively affect the quality parameters of the 3D-printed cookies while enhancing the aroma of the flour.

Short-range molecular order is the driving factor for starch digestibility and texture of alginate-encapsulated rice beads.

Rice grain analogues with slow starch digestibility are commonly associated with an unsatisfactory texture, often leading to consumer dissatisfaction. Alginate encapsulation has been applied to reduce the digestibility of corn and potato starch. The fine molecular structures of rice starch can greatly determine its digestibility and texture. However, it remains unclear whether a combination of alginate encapsulation and varied starch molecular structures can be employed to create rice grain analogues that offer both slow starch digestibility and an appealing texture. For the first time, the present study constructed alginate-encapsulated rice beads (as a rice grain analogue). A wide range of starch digestion rates were found among alginate-encapsulated rice beads prepared with different rice varieties, and only certain rice varieties (e.g. Subei and Nanjing) were able to result in rice beads with slower starch digestibility than their parental rice kernels. More importantly, all rice beads showed a relatively softer texture compared to their parental rice kernels. Correlation analysis showed that starch digestion rate, hardness and stickiness were all positively correlated with the ratio of short-range amorphous regions in rice bead samples, as obtained from Fourier transform-infrared spectroscopy, but not with the relative crystallinity. Collectively, these results suggest that rice beads with slower starch digestion rate and softer texture could be obtained by choosing rice varieties that develop more short-range ordered structure after cooking. © 2024 Society of Chemical Industry.

Understanding the influence of β-glucan-based superabsorbent hydrogel on the digestibility of wheat starch: Gelatinization, rheological and structural properties

This study aims to evaluate the effects of β-glucan-based superabsorbent hydrogel (βCHY) on wheat starch digestibility and elucidate the underlying mechanism. The results revealed that the incorporation of βCHY led to a significant reduction in rapidly digestible starch content of wheat starch from 71% to 44%, while concurrently increasing the levels of slowly digestible starch and resistant starch in a dose-dependent manner. From a mechanistic perspective, incorporating βCHY into wheat starch notably affected their pasting behavior and influenced the rheological properties and gel strength of resulting gels. Moreover, the addition of βCHY increased the relative crystallinity, short-range ordered degree (R1047/1024), molecular order (the full width at half maximum at 480 cm−1), and thermal stability of the starch, suggesting the formation of a more stable and ordered structure. Furthermore, the wheat starch-βCHY gel complexes exhibited large, discrete layered structures with thicker layer walls, accompanied by interspersed filament-like structures. These structural alterations may collectively contribute to the reduced digestibility of wheat starch. These findings confirmed the positive effects of βCHY on the starch digestibility, offering valuable insights into the development of innovative starch-based foods with slow digestion characteristics.

Effects of rosemary extract addition on starch bioavailability and antioxidant properties of extruded pet foods

This study aimed to investigate the effects of rosemary extract (RE) addition on the starch digestion and antioxidant properties of extruded pet foods. Pet foods were extruded using rice, round pea (RP), and wrinkled pea (WP) flours as the sole starch sources with RE incorporated at levels of 0 (control), 1.0, 10.0, and 30.0 g/kg (RE0, RE1, RE10, and RE30, respectively). High-amylose WP pet food exhibited lower damaged/gelatinized starch content compared with rice and RP pet foods. The total phenolic contents and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability of the pet foods notably increased after the addition of RE, showing a clear upward trend as the incorporation level was elevated. RE10 (except for rice) and RE30 significantly decreased the starch digestibility of pet foods according to in vitro testing, with the greatest reduction observed for the high-amylose WP sample. Although RE1 did not significantly impact the overall in vitro and in vivo starch digestibility, the treatment consistently postponed the peak times of postprandial blood glucose responses to all the three extruded diets in beagles. The results indicated that RE effectively enhanced the antioxidant properties of extruded pet foods and slowed starch digestion rates.

Persimmon leaf polyphenols as potential ingredients for modulating starch digestibility: Effect of starch-polyphenol interaction

The interaction mode between persimmon leaf polyphenols (PLP) and corn starch with different amylose content and its effect on starch digestibility was studied. Results of iodine binding test, TGA, and DSC revealed that PLP interacted with starch and reduced the iodine binding capacity and thermal stability of starch. High amylopectin corn starch (HAPS) interacted with PLP mainly via hydrogen bonds, since the FT-IR of HAPS-PLP complex showed higher intensity at 3400 cm−1 and an obvious shift of 21 cm−1 to shorter wavelength, and the chemical shifts of protons in 1H NMR and the shift of C-6 peak in 13C NMR of HAPS moved to low field with the addition of PLP. Results of 1H NMR also showed the preferential formation of hydrogen bonds between PLP and OH-3 of HAPS. Different from HAPS, PLP formed V-type inclusion complex with high amylose corn starch (HAS) because XRD of HAS-PLP complex showed characteristic feature peaks of V-type inclusion complex and C-1 signal in 13C NMR of PLP-complexed HAS shifted to low field. Interaction with PLP reduced starch digestibility and HAS-PLP complex resulted in more resistant starch production than HAPS-PLP complex. To complex PLP with starch might be a potential way to prepare functional starch with slower digestion.

Novel Pickering bigels stabilized by whey protein microgels: Interfacial properties, oral sensation and gastrointestinal digestive profiles

In the ongoing quest to formulate sensory-rich, low-fat products that maintain structural integrity, this work investigated the potential of bigels, especially those created using innovative Pickering techniques. By harnessing the unique properties of whey protein isolate (WPI) and whey protein microgel (WPM) as interfacial stabilizers, WPM-based Pickering bigels exhibited a remarkable particle localization at the interface due to specific intermolecular interactions. The rise in protein concentration not only intensified particle coverage and interface stabilization but also amplified attributes like storage modulus, yield stress, and adhesiveness, owing to enhanced intermolecular forces and a compact gel matrix. Impressively, WPM-based Pickering bigels outshone in practical applications, showcasing exceptional oil retention during freeze–thaw cycles and extended flavor release-a promising indication for frozen food product applications. Furthermore, these bigels underwent a sensory evolution from a lubricious texture at lower concentrations to a stable plateau at higher ones, offering an enriched consumer experience. In a comparative digestibility assessment, WPM-based Pickering bigels demonstrated superior prowess in decelerating the release of free fatty acids, indicating slowed lipid digestion. This study demonstrates the potential to fine-tune oral sensations and digestive profiles in bigels by modulating Pickering particle concentrations.

Possible interaction between pectin and gluten alters the starch digestibility and texture of wheat bread

This study incorporated citrus pectin in wheat bread, aiming to develop breads with both desirable texture and slow starch digestibility. Results showed that starch digestibility in wheat bread decreased over the addition of pectin, and the maximum starch digested amount decreased by 6.6 % after the addition of 12 % pectin (wheat flour weight basis). The addition of pectin transferred part of the rapidly digestible starch into slowly digestible starch, and reduced the binding rate constant between slowly digestible starch and digestive enzymes, resulting in overall reduced starch digestibility. Furthermore, the addition of 4 % pectin contributed to the development of wheat bread with softer texture and increased specific volume. Mechanistically, the lowered starch digestibility of wheat bread after the pectin addition was due to (1) residual outermost swollen layer of starch granules, (2) protein and pectin interactions, and (3) increased short-range ordering of starch. This study, therefore, suggests that the addition of an appropriate amount of citrus pectin has the potential to develop bread with both a low glycemic index and desirable texture.

Activity Test of Cassia alata L. Leaf Extract on Kidney Histopathology Damage Score of Diabetes Mellitus Model

Diabetic nephropathy is a disease experienced by diabetic patients. In this disease, damage to the glomerulus occurs. The administration of antidiabetic drugs tends to cause unwanted side effects, so there is a need for alternative treatment from herbs, one of which is Cassia alata L. Cassia alata L. leaves have chemical content such as flavonoids, alkaloids, tannins, and saponins. Flavonoids reduce blood glucose levels by increasing insulin secretion and mimetic agents, tannins slow carbohydrate digestion and saponins repair pancreatic beta cells and increase glycogen in the liver. This study aims to determine the effect of Cassia alata L. ethanol on the histopathology damage score of male white rat kidney (Rattus norvegicus) induced by streptozotocin. The test animals used were 30 male white rats divided into six treatment groups, each group consisting of five male white rats, namely the normal control group, negative control group, positive control group, treatment group with doses of 500 mg/kg BW, 600 mg/kg BW, and 700 mg/kg BW. The parameters evaluated were kidney tissue damage score and histopathology image analysis. The results showed that the ethanol extract of Cassia alata L. leaves contain alkaloids, flavonoids, saponins, and tannins. The ethanol extract of Cassia alata L. leaves in doses of 500 mg/kg BW, 600 mg/kg BW and 700 mg/kg BW has the activity of reducing the score of kidney tissue damage in male white rats and a dose of 700 mg/kg BW is the best dose in reducing the score of kidney tissue damage in diabetes mellitus models with a score of 2.

Investigating the effect of polyphenols from nuts on human carbohydrate digestion in vitro

Recent studies have documented the importance of postprandial hyperglycaemia in the incidence of chronic diseases, including type 2 diabetes. Inhibition of digestive enzymes, including membrane-bound brush-border α-glucosidases, leads to slowed carbohydrate digestion and absorption, and reduced postprandial glycemia. Nuts are widely eaten around the world and have the potential to inhibit α-glucosidases through their content of polyphenols and other bioactive compounds. According to our recent systematic review(1), no study has investigated the inhibitory effects of nut extracts on human α-glucosidase activities. Almost all studies in this area have been conducted on yeast α-glucosidase, with only a few using rat α-glucosidase. While there is no sequence homology between yeast and human α-glucosidase, there is 74% to 78% sequence homology between rat and human α-glucosidases(1). The lack of studies on the effect of bioactive compounds from nuts on human α-glucosidases, along with the growing attention to nuts as an important component of a healthy diet with the potential to reduce the risk of chronic diseases(2), highlights the need for research to evaluate the inhibitory effect of nut extracts on human α-glucosidases. The aim of the current study is to explore the inhibitory effect of extracts from nuts on human carbohydrate digestive enzymes. Walnuts and almonds were ground and defatted with hexane, extracted in 80% (v/v) acetone, and further purified using solid-phase extraction to obtain phenolic-rich extracts. The Folin–Ciocalteu assay was used to approximate the polyphenol content of the samples. Following our recently published detailed protocol(3), cell-free extracts from human intestinal Caco-2/TC7 cells were used as a source of α-glucosidase in enzyme inhibition assays, with sucrose, maltose and isomaltose as substrates and appropriate controls. The assay products were quantified using high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Glucose production in the presence of various concentrations of phenol-rich nut extracts was compared using a one-way ANOVA and half-maximal inhibitory concentration (IC50) values were calculated. The Folin–Ciocalteu data demonstrate that walnut extracts comprise a relatively high polyphenol content, with 18.1 ± 0.23 mg (epigallocatechin gallate [EGCG] equivalent) per gram of fresh weight, while almond extracts contain 0.87 ± 0.03 mg EGCG equivalent/g of fresh weight. The walnut phenolic-rich extract dose-dependently inhibited human intestinal sucrase and maltase activities (both p<0.01), with IC50 values of 1.67 mg/mL and 2.84 mg/mL, respectively. We demonstrate that phenolic-rich walnut extracts can inhibit human α-glucosidases in vitro and therefore walnuts may contribute to slowing carbohydrate digestion in humans. As such, we plan to assess the effects of walnuts on postprandial glycaemia in vivo.

Synergistic impact of ultrasound-high pressure homogenization on the formation, structural properties, and slow digestion of the starch-phenolic acid complex

The modification of starch digestibility can be achieved through the formation of complexes with polyphenols. We studied the combined impacts of ultrasound and high-pressure homogenization (UT-HPH) on the structure and in vitro digestibility of rice starch-chlorogenic acid complexes. The development of V-type complexes was supported by our findings, which also showed that synergistic UT-HPH therapy exhibited the highest absorbance value for the complexing index (0.882). Significant alterations in digestibility were also observed in the complexes, with the content of RDS decreasing from 49.27% to 27.06%, the content of slowly SDS increasing from 25.69% to 35.35%, and the percentage of RS increasing from 25.05% to 37.59%. Furthermore, a high positive correlation was found by applying the Pearson correlation coefficient in our research between RS, weight, PSD, and CI. This study presents a sustainable processing approach for utilizing chlorogenic acid in starch-rich food systems.

Natural Sweetener, Glycyrrhetinic Acid 3-O-Mono-beta-d-glucuronide, for Postprandial Hyperglycemia Management.

This study examines the inhibitory effects of a range of sweeteners on α-glucosidase. Our findings revealed that only one natural sweetener, namely, glycyrrhetinic acid 3-O-mono-beta-d-glucuronide (GAMG), derived from licorice, exhibited a mixed-type inhibition against α-glucosidase with a IC50 value of 0.73 ± 0.05 mg/mL. The fluorescence intensity of α-glucosidase was quenched by GAMG in the formation of an α-glucosidase-GAMG complex. GAMG has been shown to induce conformational changes in α-glucosidase, likely through hydrogen bonding, van der Waals force, and alkyl-alkyl interactions with amino acid residues, including Arg 281, Leu 283, Trp 376, Asp 404, Asp 443, Trp 481, Asp 518, Phe 525, Ala 555, and Asp 616. Additional animal validation experiments demonstrated that GAMG slowed starch digestion, thereby attenuating the postprandial glycemic response. Taken together, these findings provide evidence that GAMG is a natural sweetener with potent inhibitory activity that selectively targets α-glucosidase. This study supports the use of GAMG as a natural sweetener, which holds a high biological value and may be beneficial for managing postprandial hyperglycemia.

Effects of continuous and repeated dry heat treatment on the technological properties of green banana (Musa paradisiaca) starch

Starch is an important ingredient used in numerous industrial applications. The utilization of nonconventional sources of this carbohydrate enables the improvement of functional properties and reduces waste from certain botanical sources such as green bananas. This study aimed to evaluate the effects of dry heat modification with varying cycles (1–3) and times (3–9 h) on the thermal, paste, structural, and morphological properties, and digestibility of green banana starch, comparing them with native starch. The gelatinization enthalpy decreased with the applied treatment, especially for starches treated with repeated cycles. The peak viscosity, as observed in the RVA curve, decreased after treatment. X-ray diffractometry remained unchanged, while relative crystallinity decreased. The morphology exhibited slight alterations after the treatment. The slow digestibility of the treated starches showed a significant increase compared to the digestibility of native starch.