Slowly Digestible Starch Research Articles

Structural characterization and in vitro digestibility of rice starch processed with the combination of ultra‐high pressure homogenization, debranching, and temperature‐cycled crystallization

AbstractThis study examined the structural characterization and in vitro digestibility of rice starch processed with the combination of ultra‐high pressure homogenization (UHPH), debranching, and temperature‐cycled crystallization under various pressures (0–160 MPa). After UHPH treatment, the degree of branching (DB) of processed starches (0.65%–2.03%) was lower than that of the native rice starch (NS, 2.96%). Assessment of chain length distribution suggested that the considerable amylose was produced after treatments. Processed starches exhibited an irregular fragmented structure, and the crystalline structure was transformed from A‐type (native rice starch) into B + V‐type (processed starches). Moreover, the relative crystallinity (RC) and the absorbance ratio of 1047/1022 cm−1 (R1047/1022) of processed starches decreased from NS (RC, 22.99%; R1047/1022, 0.79) to 13.47%–18.21% (RC) and 0.51–0.78 (R1047/1022), respectively. Iodine binding curves revealed that processed starches possessed the higher degree of polymerization (DP). Furthermore, the contents of slowly digestible starch (SDS) and resistant starch (RS) increased in all processed starches, and the RS content of starch treated under 160 MPa (35.33%) was notably greater than that of native starch (9.37%). These results suggested that the UHPH can be used as a pretreatment strategy to reduce the digestibility of starch products.Practical applicationsUHPH pretreatment disrupts starch molecular chains to produce the large amounts of short linear amylose. Debranching followed by temperature‐cycled crystallization can increase the content of resistant starch (RS), yielding a raw material suitable for boosting the health of the digestive system and overall health. Therefore, UHPH pretreatment has a high application value in the field of starch modification.

Effect of Oat Beta-Glucan on Physicochemical Properties and Digestibility of Fava Bean Starch.

The current research examined the impact of different concentrations of oat beta-glucan (OG) on the in vitro digestibility of fava bean starch (FS). Our pasting analysis demonstrated that OG effectively decreased the viscosity and regrowth of FS, suppressing its in situ regrowth while enhancing the in vitro pasting temperature. Moreover, OG markedly diminished amylose leaching and minimized the particle size of the pasted starch. Rheological and textural evaluations demonstrated that OG markedly diminished the viscoelasticity of the starch and softened the gel strength of the composite system. Structural analysis revealed that hydrogen bonding is the primary interaction in the FS-OG system, indicating that OG interacts with amylose through hydrogen bonding, thereby delaying starch pasting and enhancing the gelatinization characteristics of FS gels. Notably, the incorporation of OG resulted in a reduction in the levels of rapidly digestible starch (RDS) and slowly digestible starch (SDS) in FS, accompanied by a notable increase in resistant starch (RS) content, from 21.30% to 31.82%. This study offers crucial insights for the application of OG in starch-based functional foods.

Physicochemical Characterization of In Situ Annealed Starch and Its Application in a Fermented Dairy Beverage

In this study, the aim was to modify the starches of three different sweet potato varieties—Rosada Uruguaiana (RU), Rosada Canadense (RC), and Ligeirinha (L)—through in situ annealing to increase the content of slowly digestible starch (SDS), which has health benefits. The modified carbohydrate was then added to a dairy beverage fermented by Lactobacillus casei 1e (L. casei). After annealing, the starches had different physicochemical properties, and the L variety, which had the highest SDS content, was chosen for the formulation of the fermented dairy beverage. Two concentrations of modified starch (7% and 10.5%) were used in the formulations, and a sensory analysis indicated no differences in acceptance and purchase intention. The beverage containing 10.5% modified starch exhibited good physicochemical and microbiological stability. This study demonstrates the possibility of creating a functional fermented dairy beverage with high SDS content, which could potentially benefit consumers’ health.

Digestion inhibition of potato starch-botanical proteolytic polypeptides complexes subjected to heat moisture treatment based on steric hindrance and enzymatic inhibition

The effects of food components on starch digestibility is a prominent topic within the realms of food and nutritional science. In this study, complexes of potato starch (PS) and botanical proteolytic polypeptides (BPPs), including wheat peptides, maize peptides, rice peptides, and soybean peptides, were subjected to heat-moisture treatment (HMT). The physicochemical, structural, and digestibility variations of the PS-BPPs complexes were analyzed using polarized light microscopy, DSC, X-ray, FT-IR, SAXS, and in vitro simulated digestion. Additionally, we evaluated the inhibitory effects of BPPs on porcine pancreatic α-amylase (PPA). The results showed that the polarization cross of PS-BPPs complexes was weakened after HMT. The gelatinization temperatures (To, Tp, Tc) of the PS-BPPs complexes increased significantly. The starch in the PS-BPPs complexes transitioned from B-type structure to A-type structure after HMT, accompanied by an increase in short-range ordering and semicrystalline lamella thickness. In particular, the complexes exhibited higher contents of slowly digestible starch (SDS) and resistant starch (RS). Furthermore, wheat, rice, and soybean peptides exhibited a mixed type of competitive inhibition against PPA, whereas maize peptides exhibited competitive inhibition. The findings provide valuable insights into the role of BPPs in regulating starch digestion. Moreover, BPPs hold potential for enhancing the nutritional value and health benefits of foods.

Rod-Shaped Starch from Galanga: Physicochemical Properties, Fine Structure and In Vitro Digestibility.

This work investigated the physicochemical properties, structural characteristics, and digestive properties of two non-conventional starches extracted from Galanga: Alpinia officinarum Hance starch (AOS) and Alpinia galanga Willd starch (AGS). The extraction rates of the two starches were 22.10 wt% and 15.73 wt%, which is lower than widely studied ginger (Zingiber officinale, ZOS). But they contained similar amounts of basic constituents. AOS and AGS showed a smooth, elongated shape, while ZOS was an oval sheet shape. AOS and ZOS were C-type starches, and AGS was an A-type starch. AOS showed the highest crystallinity (35.26 ± 1.02%) among the three starches, possessed a higher content of amylose (24.14 ± 0.73%) and a longer amylose average chain length (1419.38 ± 31.28) than AGS. AGS starch exhibits the highest viscosity at all stages, while AOS starch shows the lowest pasting temperature, and ZOS starch, due to its high amylose content, displays lower peak and trough viscosities. Significant differences were also found in the physicochemical properties of the three starches, including the swelling power, solubility, thermal properties, and rheological properties of the three starches. The total content of resistant starch (RS) and slowly digestible starch (SDS) in AOS (81.05%), AGS (81.46%), and ZOS (82.58%) are considered desirable. These findings proved to be valuable references for further research and utilization of ginger family starch.

The impact of slowly digestible and resistant starch on glucose homeostasis and insulin resistance.

This review will summarize recent studies assessing the effect of slowly digestible starch (SDS) and resistant starch (RS) on glucose metabolism in healthy, prediabetic or type 2 diabetic adults. Currently, a particular interest in starch and its digestibility has arisen, with data showing a positive effect of SDS and RS on the glucose homeostasis of healthy, at-risk, prediabetic and type 2 diabetic patients but research is ongoing. Carbohydrates (CHO) and especially starch play a major role in the prevention and management of metabolic diseases such as type 2 diabetes (T2D). This largely depends on the quality and the digestibility (rate and extent) of the ingested starchy products, beyond their quantity. SDS have been poorly studied but display a beneficial effect on reducing glucose excursions in healthy and insulin-resistant subjects and a relevant potential to improve glucose control in type 2 diabetic individuals. As for RS, the results appear to be encouraging but remain heterogeneous, depending the nature of the RS and its role on microbiota modulation. Further studies are needed to confirm the present results and investigate the potential complementary beneficial effects of SDS and RS on long-term glucose homeostasis to prevent cardiometabolic diseases.

Germination-induced modifications of starch structure, flour-processing characteristics, and in vitro digestive properties in maize

Current research on maize germination suffers from long sampling intervals, and the relationship between the starch structure and the processing properties of flour in maize is still unclear. This study observed the effect of germination on the structure and composition of maize starch and the processing properties of maize flour over a 72 h period using a short interval sampling method. At 36 h, the short-range ordered structure, crystallinity, and enthalpy of starch reached the highest values of 1.02, 34.30%, and 9.90 J/g, respectively. At 72 h, the ratios of rapidly-digested starch (RDS) and slowly-digested starch (SDS) enhanced to 29.37% and 28.97%; the RS content reduced to 35.37%; and the flow properties of the starch were improved. This study enhances the understanding of the effects of germination on the processing properties of maize starch and flour, determines the appropriate application, and recommends the use of germination in the food industry.

Improvement of amylose-lipid complex and starch digestibility profiles of corn starch added with rice bran oil or linoleic acid using ultrasonic and microwave treatment.

Different processing conditions can result in the creation of amylose-lipid complexes. This study investigated the effect of ultrasonication (sonication times 0, 15, 30, and 45min) and microwave (SM) heating on the amylose-lipid complex formation of corn starch added with rice bran oil (RBO) or linoleic acid (LA). Microwave heating treatment promoted the formation of starch-lipid complexes displaying V-type crystalline structure, with B + V and V-types present in corn starch treated with RBO or LA. After 30min of sonication, the contents of RBO_SM and LA_SM were greater in resistant starch (RS) and slowly digested starch (SDS), but lower in apparent amylose. Enthalpy measured using a differential scanning calorimeter was enhanced by sonication and microwave heating. The RBO_SM and LA_SM treatments resulted in increased SDS and RS contents, respectively. These findings suggested lipid that ultrasonic and microwave techniques had the potential to improve amylose- complexes and simplify the development process for RS starch preparation.

Characterization of hydrogel beads constructed from gelatinized lotus rhizome starch and sodium alginate by calcium cross-linking

The purpose of this study was to construct calcium cross-linked gelatinized lotus rhizome starch (LRS)/sodium alginate (SA) hydrogel beads of adjustable quality and to reduce the digestibility of gelatinized starch. LRS was mixed with SA, gelatinized by heating and subsequently cross-linked with Ca2+ to form hydrogel beads. The digestibility of the gelatinized LRS could be adjusted by changing the dose of SA in the hydrogel beads. When the LRS/SA ratio was 4/6, the rapidly digested starch (RDS) content in the beads was reduced by 26.9% compared with gelatinized LRS alone, whereas the slowly digested starch (SDS) and resistant starch (RS) contents increased by 12.3-fold and 2.3-fold, respectively. In addition, the water distribution in the Ca2+-crosslinked LRS/SA hydrogel bead samples also showed an SA dose dependence. With increasing SA concentration, the ability of the hydrogel beads to immobilize water increased. The diffusion of Ca2+ into the interpenetrating polymer network that was prepared with gelatinized LRS and SA gradually resulted in gelation dominated by ion bonds, leading to the heterogeneous microstructure of the hydrogel beads, which also involved intermolecular hydrogen bond interactions. Overall, the present study suggested a strategy for developing novel LRS hydrogel bead systems for quality control and gelatinized starch digestibility downregulation by adjusting the SA dose, which provided insights for the innovation of personalized and convenient starchy products in the food industry.

Comparison and inhibition mechanism study on the in vitro digestibility of rice starch complex with soy β-conglycinin and soy glycinin

To inhibit the digestion of indica rice starch (IRS), an excellent strategy was to add exogenous proteins that interact with IRS, which was closely associated with the protein components. Herein, this study compared the effects of soy protein subfractions, soy β-conglycinin (7S) and soy glycinin (11S), on IRS digestion and explored its inhibition mechanisms. This study used hydrothermal processing to prepare IRS complexes with soy protein subfractions (7S and 11S) at different starch-protein ratios. The results found that adding 7S and 11S exhibited different inhibitory patterns on starch digestion. Compared to IRS, a higher slowly digestible starch (SDS) content (40.91%, p < 0.05) was observed at the IRS-7S ratios of 20:8, while the 20:6 IRS-11S complex showed a higher resistant starch (RS) content (15.76%, p < 0.05). Subsequently, the interactions between IRS and soy protein subfractions and their multi-scale structural changes were explored. The rheological results revealed that hydrophobic interaction and hydrogen bonding were the main driving forces. Various structural changes were closely associated with inhibitory modes of soy protein subfractions on IRS digestion. In detail, the increased SDS content in IRS-7S complexes was attributed to the formation of compact protein physical barriers, aggregated structures with more ordered regions, and flexible secondary conformations of 7S. However, the high-density structures and the stable secondary conformations of 11S were responsible for the increased RS content in IRS-11S complexes. Thus, this study could provide directions for developing SDS-enriched or RS-enriched starch-based products.

The effects of fermentation time on sourdough bread: An analysis of texture profile, starch digestion rate, and protein hydrolysis rate.

To ensure the best quality bread, it is important to consider the speed of digestion of starch and proteins, as well as how time fermentation and storage time influence the rate of starch digestion and the texture of the bread. This study compared the effect of fermentation time and days of storage on the texture, physicochemical, protein and starch digestibility of sourdough bread. Texture profile analysis showed that the fermentation time in recently baked sourdough bread affects hardness, chewiness, and springiness. The electrophoretic profile showed a decrease in band thickness with increase in fermentation time, consistent with a higher percentage of protein digestion. While fermentation time did not significantly affect rapidly digestible starch (RDS) and slowly digestible starch (SDS), storage time resulted in a decrease in RDS and an increase in SDS. Sourdough breads had higher levels of resistant starch (RS). The digestibility characteristics of protein and starch, as well as texture properties, are significantly influenced by fermentation and storage time. The evidence suggests that sourdough bread has the potential to improve the digestion of protein and to effectively regulate the glycemic response, which is due to its higher levels of SDS and RS.

Physicochemical, Rheological Properties, and In‐Vitro Starch Digestibility of Flours and Starches from Pigeon Pea, Cowpea, Pinto Bean, and Navy Bean

AbstractThe physicochemical, rheological properties, and digestibility of flours and starches from pigeon pea, cowpea, pinto bean, and navy bean are investigated. Pinto bean flour (PBF) and Pinto bean starch (PBS) show the highest water absorption capacity (WAC), while cowpea flour (CPF) and cowpea starch (CPS) show the highest oil absorption capacity (OAC)‐ than other pulse flour or starches. All pulse flours show higher solubility than all pulse starches. However, the swelling power (SP) of all flours is lower than starches and SP is comparatively different among starches. Paste clarity, and relative crystallinity (RC), are higher in all flours compared to starches. However, pasting properties and consistency index (K) are lower in flour compared to starches. All the flours and starches exhibit CA‐type crystallinity.The Scanning Electron Microscrographs reveals smooth granular surfaces of all starch and flour. Both flours and starches show flow behavior (n &lt; 1) and viscosity decreased with increasing shear rate indicating the non‐Newtonian fluid behavior. All starches show higher rapidly digestible starch (RDS) and resistant starch (RS) content but lower slowly digestible starch (SDS) content than all flours. These flours and starches can be used as valuable ingredients for formulating functional food, soup, and starch gel.

A study on influences of an induced electric field on the Enzymolysis of water caltrop starch by Pullulanase

SummaryOurs is a study on the influences of an induced electric field on the physicochemical properties, structure and in vitro digestion of water caltrop starch by Pullulanase. The distribution range of molecular weight, the average molecular weight of enzyme‐treated starch, and induction electric field decreased gradually. The amylose content and gel strength of starch samples increased gradually when 50 V, 75 V and 100 V induced electric fields were applied, and the solubility and swelling power decreased with the increase of voltage. When the induced voltage was 100 V, amylose content reached 85.78%, gel strength was 198.56 g, the content of slowly digestible starch (SDS) was 41.34%, and the expected glycaemic index (eGI) was the lowest, 1047/1022, and crystallinity was higher than that of other treated samples. When the induced voltage continued to rise to 125 V and 150 V, the amylose content and gel strength of starch began to decrease, corresponding solubility and swelling power began to increase, and the short‐range order and crystallinity of starch were reduced. The content of SDS decreased gradually and eGI increased. This study provides a reference for research on the modification of starch by induction electric field.

Effect of hydrolysis of sweet potato starch by pullulanase enzyme on the formation of slowly digestible starch

The benefits of slowly digestible starch (SDS) are a slow or moderate increase in postprandial blood glucose levels and the maintenance of steady blood glucose levels. These created good conditions for diabetes control, satiety-hunger, physical and mental performance. Therefore, products related to slow digestion have attracted many researchers in recent years. In this research, technological factors affecting the formation of SDS from sweet potato starch (SPS) by the branching enzyme pullulanase were studied. These factors included SPS concentration, pullulanase enzyme concentration, pH, temperature, and hydrolysis time of pullulanase enzyme. The results showed that the maximum SDS yield was obtained by debranching for 5 hrs with an enzyme concentration of 20 ASPU/g, reaction temperature of 55°C, pH of 5.0, and a SPS concentration of 10% (w/w). In these conditions, the SDS content of SPS reached 28.04%. The findings indicated that sweet potato starch can be used as a raw material at a low cost and is feasible in the production of SDS which provides benefits for human health.

Effect of different heat-moisture treatment times on the structure, physicochemical properties and in vitro digestibility of japonica starch

Modified starch was prepared from japonica starch (JS) by heat-moisture treatments (HMT). Under the same moisture content and HMT temperature, the effects of various HMT times on the structural, properties of JS and its in vitro digestibility properties were investigated. The results showed that adhesion occurred between the particles of japonica starch after the HMT, and there were depressions on the surface. The size of the JS particles increased, the short-range ordering and relative crystallinity of the HMT-modified starch increased and gradually decreased, reaching a peak of 36.51 % at 6 h, as the HMT time was extended. The pasting indexes of HMT-modified starch decreased and then increased with the increase of the HMT time; compared with JS, the thermal stability of HMT-modified starch increased while the pasting enthalpy decreased. All the HMT-modified starches were weakly gelatinous systems and pseudoplastic fluids. Following HMT, the amount of resistant starch (RS) and slowly digested starch (SDS) grew initially before declining. The amount of RS in HMT-modified starch peaked at 24.28 % when the HMT time was 6 h. The results of this research can serve as a theoretical foundation for the creation of modified japonica starch and its use in the food industry.

Heat-moisture and acid treatments can increase levels of resistant starch in arrowroot starch without adversely affecting its prebiotic activity in human colon microbiota.

Carbohydrates are an important macronutrient whose processing and digestive fate can have numerous beneficial or adverse effects on consumer health. This study investigated the impact of heat-moisture treatments (HMT) and citric acid treatments (CAT) on arrowroot starch (ARS) with a focus on its physicochemical properties, digestibility, and influence on gut microbiota. The results revealed that HMT and CAT did not alter the colloidal characteristics of ARS but significantly affected the balance between amorphous and crystalline regions. Changes in thermal properties, morphology, and particle size were also observed. These can influence ARS shelf life and functional properties in various food applications. Furthermore, certain treatments in both processing methods increased the resistant starch (RS) content of ARS, with HMT for 16 hours at 80 °C and CAT with 0.6 M citric acid, resulting in the most pronounced effects. These changes coincided with reductions in rapidly digestible starch (RDS) levels and improvements in the ratio of slowly digestible starch (SDS) to RDS, which could potentially improve glycemic control. This study also examined the impact of processed ARS on colonic microbiota composition. It found that ARS-derived RS formed under HMT and CAT did not negatively affect the prebiotic potential of the RS fraction. Both treatments were associated with lowering the Firmicutes to Bacteroidetes ratio (F/B), a marker of gut health, and decreasing the relative abundance of Proteobacteria, microbes associated with adverse health effects. Additionally, CAT-derived RS showed a significant increase in the relative abundance of Roseburia, a beneficial gut bacterium. In conclusion, processing ARS through HMT and CAT techniques has the potential for enhancing its RS content, improving its glycemic impact, and positively influencing the gut microbiota composition, potentially contributing to gut health and metabolic well-being.

Effect of Resistant Starch from Green Banana Flour on Sensorial Properties of Noodles

Starch, a complex carbohydrate found in plants, plays an important role in human and animal nutrition. It comes in a variety of forms, including resistant starch, slowly digestible starch (SDS), and digestible starch (RDS). Resistant starch offers numerous health benefits. Resistant starch fermentation results in short-chain fatty acid production, benefiting the body by reducing cholesterol, inhibiting pathogens, and nourishing colon cells. Innovations in starch processing, like green banana flour, have expanded starch’s applications in the food industry, enhancing its nutritional value. In noodle production, wheat flour can be substituted with green banana flour to provide a healthier and safer alternative. Numerous aspects were examined in the research, including dough characteristics, texture, cooking quality, sensory evaluation, and glycemic index. The findings revealed changes in dough properties, texture, and cooking quality when resistant starch sources were incorporated. This might lead to the production of low-glycemic, healthier food items without compromising sensory attributes.

Effect of retort processing, containers and motion types on digestibility of black beans (Phaseolus vulgaris L.) starch

SummaryWith the growing demand for convenient and shelf‐stable canned beans, understanding the changes in starch digestibility due to retort processing is crucial for optimising nutritional quality and enhancing consumer health. The present study investigated the impact of retort processing, specifically container type and agitation, on the digestibility of black bean starch. Retort pouches exhibited a more rapid heat transfer rate to the enclosed product than cans, which reduced the overall processing duration. Also, the processing time to achieve a Fo = 6 of Clostridium botulinum was almost 2.5 min (pouches) and 3.2 min (cans) faster for the oscillating than the static mode. The in vitro digestibility data revealed that the retort processing of black beans led to an increase in rapidly digestible starch (RDS) from 10.51% to 32.11%. However, slowly digestible starch (SDS) decreased from 15.67% to 7.89%, and resistant starch (RS) decreased from 47.91% to 11.86%, regardless of the container type and motion involved. Processing enhanced starch digestibility in all the combinations of container and motions; nevertheless, black beans in pouches with oscillatory motion still contain a relatively significant amount of SDS and RS than the other combinations. These findings have important implications for the food industry in optimising processing techniques and packaging strategies to preserve the nutritional value of black beans. The findings of this study can have practical implications for food producers engaged in the retort processing of foods contained in pouches and cans. The investigation will provide insights into how the process of retort sterilisation affects digestibility, including slowly digestible starch and resistant starch of different types of starch.

Effects of single and dual modifications with debranching and heat-moisture treatments on physicochemical, rheological, and digestibility properties of proso millet starch

The effects of single and dual modifications with heat-moisture treatment (HMT) and enzymatic debranching on the structural, physicochemical, rheological, and in-vitro digestibility properties of proso millet starch (PMS) were comparatively studied. Amylose content increased after gelatinization and all modification treatments. Debranching and dual modification (debranching followed by HMT) decreased the average chain length and swelling power but increased the solubility of PMS. HMT did not change the average chain length and chain length distribution in native and debranched starches but decreased the swelling power and solubility of native starch. The A-type X-ray diffraction pattern of PMS was converted to the A + V type by HMT and to the B + V type by debranching and dual modification. FTIR investigation showed that the short-range molecular order of all modified starches was disrupted. The viscoelasticity and viscosity of all starch pastes decreased in the following order: PMS > HMT starch > debranched starch > dual modified starch. In-vitro starch digestibility showed that HMT increased slowly digestible starch (SDS) to 32.88 %, while debranching increased resistant starch (RS) to 77.14 %. HMT increased RS to 86.17 % in the dual modified starch. Debranching therefore predominates in the dual modification of starch compared to HMT.

Physicochemical properties of different size fractions of potato starch cultivated in Highland China

Location influences the properties of potato starch. Potato starch granules cultivated in highland of China were separated into three fractions according to the sedimentation time: large- (∼81 μm, large fraction potato starch, LFPS), medium- (∼28 μm, medium fraction potato starch, MFPS), and small-size (∼15 μm, small fraction potato starch, SFPS) fractions. SFPS showed a spherical shape, MFPS showed an ellipsoid shape and LFPS showed an elongated shape. The three fractions showed the similar XRD patterns, while the relative crystallinity decreased with the decrease of granule size (LFPS 23.61%, MFPS 20.74% and SFPS 20.48%). The water solubility was positively corelated with the granule size, while the swelling power showed a negative relationship with the granule size. For the rheological properties, all the three fractions showed a shear-shinning behavior; and SFPS had the highest peak temperature. However, the MFPS showed the lowest storage modulus during the temperature sweep. The granule size didn’t influence the nutritional properties of potato starch and LFPS had the highest slowly digestible starch (SDS) (83.77%) and resistant starch (RS) (13.66%) contents. Some of the properties are different from the previous studies.