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This study aimed to evaluate the effect of gamma irradiation at dose levels of 0, 1, 3 and 5kGy on the chemical composition, starch digestibility, pasting properties and cooking properties of two varieties of polished rice (Sakha104 and basmati). The results showed that the highest dose of gamma irradiation decreased the apparent amylose content, peak viscosity water absorption and minimum cooking time; while the fat absorption and solid loss were slightly increased. Irradiation showed increases in rabidly digestible starch (RDS) and slowly digestible starch (SDS), with consequent reductions in resistant starch (RS) for Sakha104variety. Furthermore, basmati rice displays a linear behavior over the range of radiation doses for RDS and SDS with a reduction in RS.

Simiao rice is a variety of long-grain Indica rice popular in South China. However, researches on the milling technology of Simiao rice are limited. The effect of different degrees of milling (DOMs) of Simiao rice (0–12%) were evaluated in terms of the physicochemical properties and in vitro starch digestibility of the rice. The results showed that, as the DOM increased from 0 to 12%, the head rice yield (HRY) and the content of protein, lipid, dietary fiber, vitamin B1, vitamin E and niacin nonlinearly decreased, while the content of total starch and amylose and paste viscosity parameters nonlinearly increased. The differences in chemical constituents between the brown and milled Simiao rice with different DOMs lead to the variation in their pasting properties and in vitro digestibility. Because of lower content of slowly digestible starch (SDS) and resistant starch (RS), milled Simiao rice exhibited greater digestibility and a higher estimated glycaemic index (EGI). The EGI of Simiao rice ranged from 77.98 to 85.55, and remained almost constant (approximately 84) when the DOM was above 4%. Correlation analysis indicated that the EGI had strong negative correlations with lipid, protein, dietary fiber and RS, but a positive correlation with amylose. These results provide theoretical guidance for the production of Simiao rice with desired physicochemical properties and digestibility by adjusting the DOM.

Physicochemical, functional, and nutritional properties of flours from six navy bean varieties cultivated in two different locations in Manitoba, Canada were evaluated. The effect of genotype was found insignificant for protein content, ash content, zeta potential, and surface hydrophobicity among physicochemical properties (p > 0.05). For protein content, total starch content, and zeta potential of navy bean flours, environmental factors were found significant (p 0.05). In vitro protein digestibility results varied by genotype. Although in vitro protein digestibility corrected amino acid score values were significantly affected by genotype, environment, and their interactions similar to slowly digestible starch. The current study established a better understanding of the varietal effects of genotype and environment on a wide range of properties of navy bean flours.

Pea flour was extruded at 50, 70, and 90 °C. The in vitro digestibility and characteristics of native and extruded pea flour were investigated. The in vitro starch digestibility (IVSD) and in vitro protein digestibility (IVPD) of the extruded pea flour were higher than those of the native pea flour and increased with increasing extrusion temperature from 50 to 90 °C. The rapidly digestible starch increased to 28.34% at 90 °C, the highest slowly digestible starch (SDS) content was 22.70% at 50 °C, and resistant starch content decreased to 4.71% at 90 °C. The IVPD increased from 80.94% relative to the native pea flour to 90.21% at 90 °C. Improved swelling power enabled the extruded pea flour to exhibit better performance and higher breakdown viscosity and lower setback viscosity than the native pea flour demonstrated that extrusion reduced the thermal stability and retrogradation tendency. Increasing extrusion temperatures greatly reduced the relative crystallinity (based on X-ray diffraction analysis) from 32.69% relative to the native pea flour to 9.76% at 90 °C. Extrusion treatment also reduced β-sheet content (based on Fourier transform infrared spectroscopy analysis) from 36.40% relative to the native pea flour to 31.79% at 90 °C. IVPD and IVSD improved, and the SDS content increased at 50 °C and 70 °C, thereby indicating that extruded pea flour can be applied to healthy food products.

BACKGROUND: There is a growing interest to increase dietary fiber (DF) consumption due to the health benefits associated with this nutrient. Pulses are considered a good source of non-digestible carbohydrates. The aim of this study was to investigate the possibility of substituting semolina with chickpea flour to increase the indigestible carbohydrate content without altering the texture of the pasta.RESULTS: Pasta was prepared by extruding semolina: chickpea blends. The protein and DF contents in the cooked pasta increased with the chickpea level with an important contribution of resistant starch (RS) to the DF values. The optimum cooking time decreased as the chickpea content increased, which was related to the degree of starch gelatinization of the raw pasta. The in vitro digestible starch content decreased with the chickpea substitution level, concomitant with the increase in the RS content. In general, the texture of the chickpea-containing pasta was similar to that of semolina pasta.CONCLUSIONS: Pending acceptability studies on these pastas may grant their promotion as good fiber sources, probably helpful in the fight against obesity and diet-related non-communicable diseases. This article is protected by copyright. All rights reserved. (Less)

Colored brown rice shows better health benefits than polished rice, and there is great interest in the design of demanded cooking manners for brown rice. This investigation concerns how the change of cooking mode can slow starch digestion of colored brown rice by inspecting mainly starch structural changes during cooking. Compared to cooking Mode 1, the soaking of Mode 2, at higher temperature, probably enhanced water diffusion into rice matrices, thus strengthening starch lamellae without apparently altering rice morphology and ordered structures such as starch polymorphs and helices. The followed heating of Mode 2, with reduced time, more sufficiently disrupted rice structures, causing less prominent nonperiodic molecular organizations. At the final cooking stage, the braising of Mode 2, having faster temperature reduction for prolonged time, leading to similar rice morphology, reduced molecular orders (e.g., helices) and probably denser amorphous regions of nonperiodic organizations. Such features tended to increase packing density of molecular chains (mainly starch) in rice matrices, thus slowing the enzyme diffusion in rice matrices and associated binding and catalysis events. In this way, a reduced starch digestion rate and increased resistant starch (RS) and slowly digestible starch (SDS) were seen for the rice following Mode 2 cooking.

Effects of repeated heat-moisture treatment (RHM) and continuous heat-moisture treatment (CHM) on structural, physicochemical, and digestibility properties of mung bean starch were investigated. Rupture and scallops appeared on the surface of starch granules and some polarization cross disappeared after CHM and RHM. Besides, CHM starch exhibited severe rupture than RHM with the same treatment time. Crystal type of CHM and RHM starch maintained A-type while crystallinity decreased first but then increased as treating time increased. Besides, the relative crystallinity, transition temperatures, ΔH, and slowly digestible starch and rapidly digestible starch content of RHM were significantly higher than CHM whereas solubility, swelling power, and pasting viscosities of RHM samples were lower than CHM under the same treating time. Overall, RHM measures have more advantages than CHM in the modification of the structural, physicochemical, and digestibility properties of starch.

This study was planned to determine in vitro glycemic indices of some traditional foods frequently consumed by Turkish nation and to evaulate their effects on nutrition. Glycemic indices of roasted chickpea, Turkish bagel, tarhana, bulgur, Turkish delight, baklava, pişmaniye and kadayıf species; white bread was taken as reference (70) and analyzed in vitro by taking digestive system model. Glycemic index of Turkish bagels and bulgur was high (> 70), medium (55-70) of tarhana and low (

Aim of this work was to evaluate the impact of bread enrichment with different concentrations of lentil flour (LF) (0 g/100g, 10 g/100g and 20 g/100g) on some physico-chemical, structural, and nutritional features of bread. The addition of LF in formulation affected its properties, leading to a darker appearance and to a more compact structure (e.g., higher density and lower gas bubble area fraction). Besides, it led to a significant rise in the protein, free glucose, and rapidly digestible starch content as well as in the expected glycemic index. Concerning the investigation of nutritional properties, starch and protein digestibility has been evaluated by the combination of different digestion models. Each type of bread was subjected to an in vivo oral phase followed by a semi-dynamic in vitro gastrointestinal digestion. During the oral and the gastric phases of digestion, bread with the greatest LF content (20 g/100g) exhibited an extensive starch digestibility and a partial protein digestibility compared to the other samples, due to its higher protein content. In contrast, during the intestinal phase, control (0 g/100g) showed a stronger starch digestibility compared with the LF samples, while no differences could be observed in terms of protein digestibility investigated by SDS-PAGE., This work has received financial support from project PID2019-107663RB-I00 from the Spanish Ministry of Science and Innovation (MICINN).

Due to nonuniform maturation, some plants may not be at the recommended stage of maturity when preharvest glyphosate is applied. The objective of this study was to determine how preharvest glyphosate timing affects wheat starch physicochemical properties. Two wheat cultivars were grown in three locations, and glyphosate was applied at the soft dough stage (early application) and the ripe stage (commercial standard). Upon harvest, starch chemical characteristics were studied. The proportion of B-type starch granules was lower in treated samples, although the starch molecular weight was not affected. Rapidly digestible starch content was highest when glyphosate was applied at the ripe stage, and lowest in the control, and vice versa for slowly digestible starch. Additionally, flour pasting viscosity was significantly higher in samples treated at the soft dough stage. Overall, the effects on wheat starch physicochemical characteristics were more pronounced when glyphosate was applied at the soft dough stage of maturity.

BACKGROUND Maize tortilla staling is a major drawback that affects its commercialization and consumption, and so novel methods for retarding staling are continuously being explored. The present study evaluated the effect of adding a canola oil/candelilla wax oleogel (CWO; 0. 2, 4 and 6 g 100 g-1 ) to a basic masa formulation (water, 60 g 100 g-1 ; nixtamalized maize flour, 40 g 100 g-1 ) on the texture, staling and in vitro starch digestibility of maize tortillas made using a hot plate (200 °C). RESULTS Textural analysis showed that CWO reduced hardness and increased the tensile strength of tortillas. Fourier transform infrared analysis indicated that the retrogradation of starch chains, quantified in terms of the intensity ratio 1047/1022, was reduced by oleogel incorporation. In vitro starch digestibility tests showed that tortillas containing CWO had lower readily digestible and slowly digestible starch fractions compared to the control tortilla without oleogel. CONCLUSION The formation of amylose-lipid inclusion complexes and the formation of an oily physical barrier around starch granules were postulated as mechanisms underlying the reduced starch digestibility. © 2019 Society of Chemical Industry.

To understand the mechanisms of buckwheat digestion, in vitro and in vivo digestibility of buckwheat flour (BF), buckwheat starch (BS), defatted buckwheat flour (DFBF), and deproteinized buckwheat flour (DPBF) were investigated. The results showed that fat and protein could inhibit the digestion of BS. The resistant starch content of DFBF was decreased from 4.21% to 0.83%, and slowly digestible starch content was increased from 0.66% to 8.16%, compared with BF. The in vivo digestibility results showed that DFBF or DPBF has a shorter glucose release time and higher hepatic glycogen content than BF. Scanning electron microscopy and thermodynamic properties analyses were combined to study the interaction of starch, fat, and protein of buckwheat. These results indicated that proteins could wrap around the starch granules and limit the enzymolysis of starch. Fat-starch complex limited starch hydrolysis. This study could give good guidance for making new health care products.

The use of wholemeal flour and sourdough fermentation in different food matrices has received considerable attention in recent years due to its resulting health benefits. In this study, a semolina-based and a wholemeal semolina-based sourdough were prepared and added to the formulation of gnocchetti-type fresh pasta. Four types of gnocchetti were made, using semolina plus semolina-based sourdough (SS), semolina plus wholemeal semolina-based sourdough (SWS), semolina alone (S), and semolina plus wholemeal semolina (WS). The latter two were used as controls. The digestibility of starch was studied both in vitro and in vivo, and the glycemic response (GR) and glycemic load (GL) were determined. Starch digestibility, both in vivo and in vitro, was higher in wholemeal semolina than semolina pasta and the resulting GR values (mg dL−1 min−1) were also higher (2209 and 2277 for WS and SWS, 1584 and 1553 for S and SS, respectively). The use of sourdough significantly reduced the rapidly digestible starch (RDS) content and increased the inaccessible digestible starch (IDS) content. The addition of sourdough to the formulation had no effect on the GR values, but led to a reduction of the GL of the pasta. These are the first data on the GR and GL of fresh pasta made with sourdough.

To date, how the pH conditions of thermal processing tailor the structure and digestibility of resulting starch-based complexes remains largely unclear. Here, indica rice starch (IRS), stearic acid (SA), and a whey protein isolate (WPI) were used as materials. Increasing the pH value from 4 to 8 during thermal processing (pasting) mainly suppressed the starch digestion of starch-WPI-SA complexes rather than starch-SA counterparts. The starch-SA complexes showed moderate structural changes as the pH value rose, and there was less rapidly digestible starch (RDS) only at pH 8. For the starch-WPI-SA complexes, an increased pH value allowed larger nonperiodic structures and more V-type starch crystallites, with almost unchanged short-range orders but apparently collapsed networks at pH 8. Such ternary complexes displayed more resistant starch (RS) as the pH value rose. The ternary sample at pH 8 contained ca. 29.87% of the RS fractions.

Mixtures of proso millet starch with zein (15%, w/v), soy protein isolate (SPI, 15%, w/v) and whey protein isolate (WPI, 10%, w/v) as starch–protein composites were prepared through heat–moisture treatment, and the effects of protein addition on the physicochemical, structural and digestibility properties of starch were investigated. Rapid Visco Analysis showed that the addition of zein, SPI and WPI gave significantly decreased setback values to 240.7cp, 192.0cp and 83.0cp, respectively, and setback values decreased reflected the excellent cold paste properties. Thermal analysis showed that each protein reduced the enthalpy, but especially WPI (reduced by 94.7%), suggesting that the double helices of the starch granules were decreased. X‐ray diffraction showed that starch crystallinity was decreased after protein addition. The digestibility studies revealed that the addition of zein, SPI and WPI decreased the content of rapidly digestible starch and increased the resistant starch content to 8.4%, 14.6% and 17.5%, respectively. The whey protein displayed a more obvious impact on the digestibility of proso millet starch. These results will help guide the production and processing of starchy foods with desirable properties.

The effect of Clitoria ternatea flower (CTE) incorporated into cooked rice using domestic cooking methods on starch digestibility was determined. The incorporation of 1.25% and 2.5% (w/v) CTE caused a reduction in the starch digestibility of cooked rice using an electric rice cooker. In addition, there was significant alteration on the starch digestibility of cooked rice incorporated with 2.5% CTE using a microwave oven. Moreover, CTE significantly reduced the level of rapidly digestible starch and increased the level of undigested starch in cooked rice using an electric rice cooker. In the textural characteristics, the hardness of cooked rice with CTE remained unchanged, whereas a reduction in stickiness of cooked rice with CTE was observed. The sensory evaluation of cooked rice with CTE given by panelists demonstrated a good overall acceptability. Overall, the results show that CTE is a useful ingredient to incorporate with cooked rice for reduction of starch digestibility.

Wheat flour substituted with potato pulp was applied in steamed bread to improve nutrient value and reduce the energy consumption and the cost. The dough rheology, starch–gluten network, the quality and in vitro starch digestibility of steamed bread containing 0%–50% potato pulp were investigated. The dough sample with 10% potato pulp content exhibited the optimal elastic and viscous modulus values. Scanning electron microscopy (SEM) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that dough samples with potato pulp contents of more than 30% weakened starch–gluten interaction and exhibited discontinuous network structures. Steamed bread with 30%–50% potato pulp contents showed reduced specific volumes and increased hardness. The rapidly digestible starch contents and expected glycaemic indices of steamed bread enriched with potato pulp decreased from 46.98% to 31.40% and from 87.81% to 72.79%, respectively. In conclusion, wheat flour substituted with potato pulp can be used in the energy-efficient and cost-effective production of steamed bread with improved nutritional value.

The effect of heat moisture treatment (HMT), annealing (ANN), and dual retrogradation (DR) on functional and pasting properties, digestibility of starch components of banana flour comprising rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) has been investigated, using native banana flour (NBF) as a control. Crystal type, relative crystallinity and morphological changes were characterised by XRD and SEM. HMT has markedly modified the pasting properties and resulted in the highest SDS content. HMT and ANN increased the relative crystallinity but DR decreased it. HMT and DR altered XRD patterns from B to A and A + B type respectively, while ANN did not change the XRD patterns. The NBF compact granule surface remained unchanged with ANN but changed to a more porous surface with HMT and DR, thereby increasing the digestibility. Crystal type and granule morphology affected the digestibility while relative crystallinity might change the pasting point.

Parboiling is widely used world-wide, but properties of the final products depend upon processing conditions and rice variety yielding complex results. This study intended to understand the formation of amylose lipid complex (ALC) after parboiling combined with heat moisture treatment (HMT). Differential scanning calorimetry (DSC) and X-ray diffraction were utilized to understand the properties of the parboiled rice. In vitro starch hydrolysis was employed to evaluate the digestibility of the products. The distributions of protein and starch in rice kernels were observed using a light microscope. Data from amylose content measurement using iodine indicated the formation of ALC after parboiling and HMT. The presence of type II ALC was confirmed by DSC and X-ray diffraction. Pressure cooking increased the resistant starch (RS) from 1.95 to 7.95%. Resistant starch (RS) and slowly digestible starch (SDS) were further increased to 10.4% and 45.8%, respectively, by HMT after parboiling. The data indicated that pressure cooking and HMT could increase the contents of RS and SDS of rice, along with other potential health benefits.

As part of ongoing efforts to promote millet as a double crop for the American Midwest, four Minnesota-grown proso millet varieties were selected for fresh gluten-free pasta production and compared to commercially available fresh gluten-free and wheat pasta. Raw and cooked pasta were analyzed for starch and protein content, color, and carotenoids. Cooked pasta was assessed for cooking quality, in-vitro starch and protein digestibility, and sensory quality. Millet pasta contained less rapidly digestible starch than commercial gluten-free pasta; however, millet and commercial gluten-free pasta had lower protein digestibility than wheat pasta. Sensory panelists detected more graininess and starchiness in millet samples than in commercial pasta. Millet varieties differed in amylose content and prolamin profile, and both factors influenced pasta properties. Pasta with more amylose and high-molecular weight prolamins had lower cooking loss and lower stickiness scores. Higher amylose contents also corresponded to higher firmness and chewiness among millet pasta samples. The millet sample with the lowest amylose and prolamin content yielded pasta of the lowest quality. Results indicated that select proso millet varieties may be suitable for fresh pasta, yet quality improvement is warranted by recipe or processing optimizations.

The present study compared liquid sourdough technology with baker’s yeast leavening when applied to the production of a semolina-based crispy flatbread. Following in vitro starch digestion, the results revealed the sourdough leavened flatbread to contain a lower percentage of rapidly digestible starch (16%), higher amounts of slowly digestible starch (27%) and inaccessible digestible starch (4.1%) compared with the baker’s yeast leavened flatbread (20, 20, and 2.4%, respectively), making the former nutritionally healthier. The sourdough leavened bread was crispier, stiffer and more solid, as shown by texture analyses, although Raman spectroscopy revealed no differences in the crystallinity status of starch. The descriptive analyses show that the use of sourdough enhances the positive sensory traits, as rated by the consumer panel scores (6.08 vs. 5.56). In summary, the results indicate that the implementation of sourdough technology in the production of flat crispy breads could confer economic advantages to this product. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10068-018-0530-y) contains supplementary material, which is available to authorized users.

Pullulanase (P) and ultrasonication (U) were simultaneously applied to debranch pea starch to enhance slowly digestible starch (SDS) and resistant starch (RS) fractions in the debranched pea starch (DPS). A synergistic debranching effect was found under conditions of pullulanase (40 npun/g) and ultrasonication (100% amplitude in pulse mode, 1 min on followed by 9 min off), which produced 73.5% linear glucans, 18% SDS and 26% RS in the resulting DPS-PU after 6 h of debranching. Even when autoclaving the DPS-PU at 118 °C for 30 min, following cooldown, 11% SDS and 25% RS were retained in the DPS-PU, compared with 0% SDS and 12% RS in autoclaved native pea starch. The SDS fraction in autoclaved DPS-PU further increased to 16% while the RS content remained constant during 14 days of cold storage. In summary, DPS-PU is high in linear glucans, low in starch digestibility and has a thermally stable RS fraction.

Starch digestibility is the dominant factor affecting the nutrition of starchy food. Starch with different digestibility can be obtained through tailoring the starch multi-scale structures by controlling the crop growth period. Here, the multi-scale structure and digestibility of cassava starch obtained from different cassava growth periods were investigated, and the structure-digestibility relationships were revealed. The results indicated that the cassava starch synthesized during different growth periods showed differences in digestibility. The combined total content of slowly digestible starch (SDS) and resistant starch (RS) was highest at the growth period of 7 months, and the individual content of SDS and RS was highest at the growth periods of 10 and 11 months, respectively. The multi-scale structure changes during different growth periods demonstrated that smaller weight-average molecular molar mass, larger molecular density, more ordered short-range structure, and thinner amorphous lamellae decreased starch digestion, while higher amylose content and B2 chain ratio, longer average chain length, thicker crystalline lamellae, and repeated semicrystalline lamellae contributed the formation of RS fractions. Hence, specific starch structures can be tailored by simply controlling the growth period for obtaining slow and resistant digestible cassava starch to improve its nutritional value.

Pasta is a carbohydrate-rich food with a low glycemic index (GI) and is one of the main sources of slowly digestible starch (SDS). The presence of bran fractions (BFs) in pasta may enhance its health potential, owing to the content of fiber, micronutrients, and bioactive compounds, however, at the same time, BF may affect starch digestibility. In this study, the bioaccessibility of starch in pasta made with BF-enriched semolina (BF pasta), or only with micronized debranned kernel (DK pasta), and a control pasta made with traditional semolina was evaluated by applying two different in vitro models. The control pasta showed a percentage of SDS about four-fold higher than that of the BF pasta and 1.5-fold higher than that of the DK pasta (p &lt, 0.05). The amount of starch released during simulated gastrointestinal digestion was slightly lower, but not significantly different, for the control pasta than for both the BF and DK pasta. These results suggest that the presence of a higher amount of dietary fiber in BF pasta can affect the structure of the food matrix, interfering with the formation of the gluten network, water absorption, and starch granule accessibility, while micronization could enhance starch digestibility due to starch gelatinization. These findings emphasize the need to optimize the process for producing fiber-rich pasta without affecting its low starch digestibility and, consequently, its GI.

The functionalities of gluten-free rice noodles are significantly affected by starch hierarchical structures. Identifying the structures that synergistically determine noodle integrated functionalities is vital to designing health-promoting starchy foods with desirable consumer sensory and nutritional qualities. This study reports on the changes in starch structures and functionalities (starch digestibility, texture, and flavor) of rice noodles during household cooking processes (steaming, boiling, and stir-frying), and describes an underlying structure-functionality relationship. Results show that all the cooking processes examined increased starch reassembled ordered structures, especially short-range ordered structures, helical and crystalline structures, and ordered aggregate structures. Steaming and boiling led to a decrease in rapidly digestible starch (RDS) and an increase in slowly digestible starch, while stir-frying yielded a reduction in RDS content and an increase in resistant starch in rice noodles. Steaming and boiling decreased while stir-frying increased the flavor variety of noodles. All cooking processes examined altered noodle textures, with a significant increase in hardness, gumminess, and chewiness. Structure-functionality relationships suggested short-range ordered structures, crystalline structures, and the ordered molecular and aggregate structures of noodles synergistically determined starch digestion, texture, and flavor. By structuring such key structures, the digestion, texture, and flavor of rice noodles can thus be reasonably controlled.

During processing of cereal-based food products, starch undergoes dramatic changes. The objective of this work was to evaluate the impact of food processing on the starch digestibility profile of cereal-based foods using advanced imaging techniques, and to determine the effect of preserving starch in its native, slowly digestible form on its in vivo metabolic fate. Four different food products using different processing technologies were evaluated: extruded products, rusks, soft-baked cakes, and rotary-molded biscuits. Imaging techniques (X-ray diffraction, micro-X-ray microtomography, and electronic microscopy) were used to investigate changes in slowly digestible starch (SDS) structure that occurred during these different food processing technologies. For in vivo evaluation, International Standards for glycemic index (GI) methodology were applied on 12 healthy subjects. Rotary molding preserved starch in its intact form and resulted in the highest SDS content (28 g/100 g) and a significantly lower glycemic and insulinemic response, while the three other technologies resulted in SDS contents below 3 g/100 g. These low SDS values were due to greater disruption of the starch structure, which translated to a shift from a crystalline structure to an amorphous one. Modulation of postprandial glycemia, through starch digestibility modulation, is a meaningful target for the prevention of metabolic diseases.

Pulses are the major source of proteins and other nutrients in the diets of malnourished areas of the world. They are also good sources of slowly digestible starch, the most desirable form of dietary starch that is completely, but more slowly, digested in the small intestine, and attenuates postprandial plasma glucose and insulin levels. The separation of starch from pulses is difficult and generally gives lower yield, particularly when starch with high purity is required. The separation of starch of high purity from certain pulses is difficult because of the presence of highly hydrated fine fiber fractions and insoluble protein. Pulse starches are isolated using aqueous techniques (wet) and dry milling. Pulse starches can be used in processed meat products, particularly, where extensive heating and mechanical stirring is required. Canned foods, cooked sausages, soups, sauces, noodles, and vermicelli prepared using pulse starches have better sensory attributes than those made from starches from traditional sources.

With the increasingly extensive research on starch, its use in food, pharmaceutical and cosmetic industries has widely increased. This chapter summarizes the applications of starch towards edible films and coatings, the film forming abilities and recent advances in nano-composites were discussed. Starch has been used as functional ingredient in various food formulations for so many years, but currently starch from various sources is being studied and modified to improve its behavioral and functional properties. Besides this starch has also been widely used as encapsulating material for delivery of bioactive agents including probiotics, polyphenols minerals and vitamins. The use of starch for nano delivery of biomolecules and characterization of starch nanoparticles is currently of great interest for researchers.

Gluten-free (GF) biscuits were prepared by replacing part of a GF flour mix (GFM) with 0, 15, 30 and 45 g/100 g (total flour) with a novel resistant starch-rich ingredient obtained from annealed white sorghum starch (RSWS). The chemical composition, physical characteristics, in vitro starch digestion and sensory evaluation of biscuits were considered. The chemical composition of samples was influenced by the addition of the RSWS. The highest total dietary fibre and RS contents (p < 0.05) were measured in 45-RSWS biscuits. The starch hydrolysis index values decreased when the level of RSWS increased in the composite. With regard to quality parameters, the use of RSWS influenced the hardness of the biscuits, and the highest value obtained for 45-RSWS. Some of the selected sensory attributes, along with the overall acceptability score, were negatively influenced by the RSWS addition, even if all remained above the limit of acceptability. The use of RSWS in GF biscuit formulation can contribute towards the creation of food products likely having slowly digestible starch properties, and this can be achieved without drastically compromising on the quality and sensory attributes., Gluten-free; Resistant starch; Hydrolysis index; Dietary fiber; Biscuits.

International audience; BACKGROUND AND AIMS: In type 2 diabetes (T2D) patients, the reduction of glycemic variability and postprandial glucose excursions is essential to limit diabetes complications, beyond HbA1c level. This study aimed at determining whether increasing the content of Slowly Digestible Starch (SDS) in T2D patients' diet could reduce postprandial hyperglycemia and glycemic variability compared with a conventional low-SDS diet. METHODS AND RESULTS: For this randomized cross-over pilot study, 8 subjects with T2D consumed a controlled diet for one week, containing starchy products high or low in SDS. Glycemic variability parameters were evaluated using a Continuous Glucose Monitoring System. Glycemic variability was significantly lower during High-SDS diet compared to Low-SDS diet for MAGE (Mean Amplitude of Glycemic Excursions, p \textless 0.01), SD (Standard Deviation, p \textless 0.05), and CV (Coefficient of Variation, p \textless 0.01). The TIR (Time In Range) [140-180 mg/dL[ was significantly higher during High-SDS diet (p \textless 0.0001) whereas TIRs ≥180 mg/dL were significantly lower during High-SDS diet. Post-meals tAUC (total Area Under the Curve) were significantly lower during High-SDS diet. CONCLUSION: One week of High-SDS Diet in T2D patients significantly improves glycemic variability and reduces postprandial glycemic excursions. Modulation of starch digestibility in the diet could be used as a simple nutritional tool in T2D patients to improve daily glycemic control. REGISTRATION NUMBER: in clinicaltrials.gov: NCT03289494.

The industrial utilization of native starches is limited because of their poor qualities and different starch modifications are used to improve functionality of starch. Physical modification of starch is preferred since it is simple, inexpensive, and specially it does not involve any chemical reagents. Physical modifications can be divided into thermal and non-thermal treatments. These techniques alter physicochemical properties of starch including in vitro digestibility, which indicates the nutritional value of starch. Starch nutritional fractions are of three types; RDS (rapidly digestible starch), SDS (slowly digestible starch) and RS (resistant starch). It is important to understand how physical modifications affect starch nutritional fractions as both SDS and RS have beneficial health effects and specially RS has the potential to be used as a natural bioactive compound. This review aims to summarize the recent knowledge regarding the physical modifications and their impact on in vitro digestibility and nutritional fractions of starch.

The effects of the dry heat treatment (DHT) temperature (20, 50, 100, 150, 200 °C) on the structure of wheat flour and on the texture and in vitro starch digestibility of breads were investigated. X-ray diffraction and FTIR showed that increasing temperatures produced reduction of the hydrated starch structures, increased crystallinity and molecular order of starch chains, and had important effects on the gluten secondary structure. High treatment temperatures produced significant reductions in rapidly digestible starch (RDS) (53.21% at 20 °C, 22.24% at 200 °C), and the slowly digestible starch fraction tended to increase (26.12% at 20 °C, 31.48% at 200 °C). On the other hand, bread hardness showed a significant increase from 11.25 N at 20 °C to 49.53 N at 200 °C, the latter value being similar to that reported for bread crusts. Principal component analysis results showed that the flour and bread characteristics were drastically changed by the DHT, with 100 °C representing a critical temperature. Below 100 °C, breads showed textural characteristics close to that of the control bread, with reduced RDS fractions, while at temperatures above 100 °C, hardness was boosted.

A deep-fried dough/batter food (magwinya) consumed across different age groups and social strata in South Africa was investigated in this study for digestibility and estimated glycaemic index (eGI). In this research, we investigated the influence of bran type&mdash, wheat bran (WB) and oat bran (OB), and concentration (0&ndash, 20% w/w) on the starch digestibility and eGI of magwinya. Rapidly available glucose (RAG) of control fried dough (60.31 g/100 g) was 33% less than fried batter (90.07 g/100 g). There was a significant reduction in RAG and an increase in slowly available (SAG) and unavailable glucose (UG) content of the fried products with OB and WB addition. The highest SAG content was observed in WB fried dough. Control fried batter had the highest eGI value (80.02) and control fried dough had medium eGI value (58.11). WB fried dough, fried batter, and OB fried dough were categorised as medium GI foods at eGI range of 56.46&ndash, 58.39, 65.93&ndash, 68.84 and 56.34&ndash, 57.27, respectively. The eGI values of OB fried batter ranged from 73.57 to 80.03 and were thus classified as high GI foods. UG showed significant correlation with eGI (r = &minus, 0.892, &minus, 0.973, p &lt, 0.01) and fat content (r = &minus, 0.590, &minus, 0.661, p &lt, 0.01) for WB and OB fried products. These results reveal that ingredient modification through bran enrichment is effective for the regulation of starch digestion and reduction of eGI of deep-fried dough/batter foods.

In this study, waxy or normal potato starches (WPS or NPS) were blended with waxy, low-amylose or high-amylose rice starch (WRS, LARS or HARS) in different ratios (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100). Pasting profiles of blends were additively between those of the component starches separately except for some mixtures of WRS and potato starches. Twin or even three gelatinization peaks were observed for potato-WRS or potato-HARS blend, while only one peak was observed in potato-LARS blend. Addition of WRS enhanced the nutritional profile of blends containing WPS by decreasing the rapidly digestible starch level. Microscopy revealed that addition of WRS was beneficial for the development of dense and compact structure of gels of blends compared with their counterparts, which may be because few amylose chains leached to inhibit the interaction between swollen potato and rice starch granules. Besides, peak, trough, breakdown and final viscosity as well as gelatinization enthalpy showed significantly negative correlations with amylose leaching. Non-additive behaviours were observed for properties, but more independent behaviour was observed between potato starch and LARS or HARS. Results suggested that properties of blends of potato and rice starches differing in amylose content varied through different extents of amylose leaching.

Faba bean (Vicia faba L.) flour, starch concentrate (60% starch), protein concentrate (~60% protein) and protein isolate (~85% protein) were added to replace one-quarter of durum wheat semolina to enrich the nutritional quality and physiological functions of durum wheat (Triticum turgidum L.) pasta. The raw pasta samples prepared with protein concentrate or isolate had higher (p ≤ 0.001) protein and lower (p ≤ 0.001) total starch concentrations, along with increased total dietary fiber and slowly digestible starch (p ≤ 0.001) than durum wheat semolina control or those with added whole faba-bean flour or isolated starch. The faba bean fortified pasta had altered starch with increased proportion of medium B-type glucan chains and long C-type glucan chains, reduced starch digestibility and were associated with glycaemia related effects in the human diet. The faba bean fortified pasta had increased protein and dietary fiber that influenced food intake and satiety. The results suggest differential contributions of food ingredients in human health outcomes.

Proximate composition and starch nutritional properties of twenty cooked lentils were assessed to identify unique varieties that could be used in value added foods. Significant variations exist among the lentil varieties (p &lt, 0.05) with respect to their energy, fat, protein, carbohydrate, and dietary fiber content, and these are related to lentil type and seed size. Dazil and Greenstar were unique for their high resistant starch content (RS) and lower area under the starch hydrolysis curve (SHAUC) while Proclaim was opposite. SHAUC was positively correlated (p &lt, 0.001) with rapidly digestible starch (RDS) content (r = 0.626) but negatively correlated with RS content (r = &minus, 0.635). Principal component analysis showed that the first three principal components accounted for 62.8% of the total variance and the contribution of SHAUC was 33.2%. These results confirm that in vitro SHAUC and a combination of RDS and RS may be predictive of the digestibility profile of cooked lentils.

Objectives Maltase-glucoamylase (Mgam) and sucrase-isomaltase (Si) are mucosal α-glucosidases required for the digestion of starch to glucose. We hypothesized that a dietary approach to reduce Mgam and Si activities can reduce glucose generation and absorption, and improve glucose control. Methods Rice starch was entrapped in alginate microspheres to moderate in vitro digestion properties. Three groups of 8-wk old mice (n = 8) were conditioned for 7 d with low 13C-starch-based materials differing in digestion rates (fast, slow, and slower), and then given a digestible 13C-labeled cornstarch test feeding to determine its digestion to glucose. Results Conditioning of the small intestine with the slowly digestible starches for 7 d reduced jejunal α-glucosidase and sucrase activities, as well as glucose absorption for the slowly digestible starch slower group (P Conclusions Decreased glucogenesis from a digestible starch feeding was found in mice conditioned on slowly digestible starch diets, suggesting that a dietary approach incorporating slowly digestible starches may change α-glucosidase activities to moderate glucose absorption rate.

This study aimed at designing a&mdash, diet high in slowly digestible starch (SDS) by carefully selecting high-SDS starchy products and to validate its implementation, acceptance, and impact on the postprandial glycemic response in patients with type 2 diabetes (T2D). Starchy products were screened and classified as being either high (high-SDS) or low (low-SDS) in SDS (in vitro SDS method). A randomized controlled cross-over pilot study was performed: Eight patients with T2D consumed randomly a high-SDS or a low-SDS diet for one week each, while their glycemic profile was monitored for 6 days. Based on 250 food product SDS analyses and dietary recommendations for patients with T2D, the high-SDS and low-SDS diets were designed. The high-SDS diet significantly increased SDS intake and the SDS/carbohydrates proportion compared to the low-SDS diet (61.6 vs. 11.6 g/day and 30% vs. 6%, p &lt, 0.0001, respectively). Increasing the SDS/carbohydrate proportion to 50% of the meal was significantly correlated with a 12% decrease in tAUC0&ndash, 120 min and a 14% decrease in the glycemic peak value (p &lt, 0.001 for both). A high-SDS diet can be easily designed by carefully selecting commercial starchy products and providing relevant recommendations for T2D to improve their glycemic profile.

IntroductionGlucose intolerance and type 2 diabetes are increasing worldwide. Current scientific evidence tends to demonstrate that people with an Asian phenotype have a lower glucose tolerance compared to Caucasian phenotype. In addition, in Caucasian population, consumption of products with a high content of Slowly Digestible Starch (SDS) significantly decreases postprandial glycemic and insulinemic responses compared to products with a low-SDS content. The aim of this study was to evaluate the effect of consuming products with varying levels of SDS on postprandial glycemic and insulinemic responses, both in Asian and Caucasian populations.Materials and methodsFive products with varying starch digestibility profiles (determined by the SDS method developed by Englyst) and one glucose solution were tested. A randomized cross-over controlled study was set up in the University of Sydney to study the products’ Glycemic and Insulinemic Indexes (GI and II) and postprandial responses over 2 hours. 12 Caucasian and 12 Asian participants were recruited and consumed 50 g of available carbohydrates from each product (norm ISO-26642(2010)).ResultsAsian participants were 28.0 ± 2.6 yo with a body mass index (BMI) of 21.4 ± 0.3 kg/m2 and Caucasians were 26.0 ± 1.1 yo with a BMI of 22.4 ± 0.5 kg/m2 (no difference between groups). Among the products tested, 3 had a high-SDS content (26 to 28 g SDS / 100g) and 2 had a low-SDS content (0 to 2 g SDS / 100g). GI values for Asian participants ranged between 44 and 54 for high-SDS products (low GI) and were medium (64) or high (90) for low-SDS products. GI values for Caucasian participants ranged between 40 and 48 for high-SDS products (low GI) and between 60 and 79 for low-SDS products. In a statistical model including product effect, ethnicity effect, session effect, and the interaction term product*ethnicity, the product effect was the only significant parameter and products were split according to their SDS content. Furthermore, products with a high-SDS content decrease the glycemic peak value by about 1 mM, both in Asian and Caucasian participants. Consumption of high-SDS products also decreases the insulin demand by 29% and 32% in Asians and Caucasians respectively compared to low-SDS products.DiscussionOur study demonstrates that consumption of products with a high-SDS content similarly decreases the glycemic and insulinemic responses in both Asian and Caucasian participants. This decrease may be beneficial in the long term to prevent metabolic diseases.

Several grains such as wheat, rice, corn, oat, barley and rye are cultivated throughout the world. They are converted to variety of food products using a multitude of processing technologies to quench the growing organoleptic demands and consumers' preferences. Among them, corn, ranking third in wide consumption, is cost-effective and has long-term storability. Herein, ready-to-eat corn flours with variable starch digestion have been developed by processing at high temperature with shear using a twin screw continuous processor. The influence of processing temperature (121, 145 and 160°C) and moisture (25, 30 and 35%) has been studied. Results suggest both processing temperature and moisture modulate the rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) amounts of the flours. The presence or absence of oil in the flour further controls the starch digestion. The outcome is deemed to be helpful to design and develop healthy and palatable functional food products in addition to furthering the current market share for corn and other grains.

Kutki millet (Panicum sumatrense) is presently underutilized, despite its potential to deliver a relatively good source of nutrients. Series of investigations were undertaken to evaluate the functional, structural, textural, flowability, pasting, and in vitro digestibility of Kutki millet starch (KMS) taking corn starch (CS) as a control. Various starch digestibility kinetic models were fitted to the experimental data to determine their best fitting and related model parameters. KMS contains a high amount of amylose and showed better pasting, textural properties and can be explored for its various food applications as thickener, stabilizer, and gelling agent, etc. The digestion kinetic model fitting showed that all the models fitted well (R2 > 0.957) except the Paolucci-Jeabjean model (R2 = 0.923). All the models showed a lower value of an amount of initial digestible and maximum digestible starch in the case of KMS than CS. SEM micrographs of KMS showed large polygonal granules and some spherical ones, but CS showed a mixture of angular, spherical, and oval shapes. The finer particle size of KMS makes it suitable as a fat replacer. Our findings indicate that KMS can find versatile food applications and as an excellent option for industrial utilization in addition to the commonly used starches.

The aim of this study was to investigate the effect of mechanical kneading and ‘absit’ preparation difference on the quality of tef injera, the staple food of Ethiopians. Standard methods were adopted to determine the starch fraction, total phenol, flavonoid, phytate and tannins of injera. Sensory injera quality was assessed using 9-point-hedonic scale. Change in kneading conditions (time/speed) did not significantly affect the free sugar (FSG), slowly digestible starch (SDS), resistant starch (RS), total starch(TS) and starch digestion rate index (SDRI). On the other hand, significant variation was observed in rapidly available glucose and rapidly digestible starch (RAG and RDS). Flavonoids, total phenolics and phytate contents varied significantly at different kneading time- speed combinations. Injera sensory quality was also significantly affected due to change in kneading conditions. Kneading condition 5 (3 min at speed 6) has the highest injera overall acceptability while kneading condition 9 (7 min at speed 12) had the lowest. In addition to kneading conditions, absit preparation (water to fermented dough ratio) was also found to affect the quality of tefinjera. Absit # 3 made from 100 ml of fermented dough and 900 ml of water had the highest injera overall acceptability while, the lowest was observed on Absit # 4 made from 300 ml of fermented dough and 100 ml of water. In conclusion, both kneading and absit preparation significantly influenced starch hydrolysis, flavonoids, total phenolics and phytate contents as well as sensory quality of injera. Key words: Kneading, sensory quality, absit preparation, starch fractions.

This study aimed to investigate functional and thermal properties and digestibility of grass pea starch, and provide information on the effect of hydrothermal modifications - annealing (ANN) and heat-moisture treatment (HMT) on the physico-chemical characteristics of the starch and digestibility, especially after processing (cooking, storage after cooking and freezing). After heat treatment, especially after cooking and storage at a temperature of −18 °C, the total content of slowly digestible starch and resistant starch in grass pea starch was high, which may indicate its great tendency for retrogradation. The HMT and ANN modifications of grass pea starch caused changes in its crystalline structure and increased integrity of its granules, which in turn resulted in a lower swelling power and amylose leaching, however this effect was more pronounced upon HMT which contributed to starch polymorphic type transformation from C to A. Despite greater resistance of granules of modified starches to swelling during cooking their suspensions, after cooking these starches were characterized by a higher predicted glycemic index than the non-modified ones. A similar content of resistant starch determined in modified and non-modified gelatinized starches stored at lowered temperatures indicates that starch modifications, HMT in particular, cause no changes in its susceptibility to retrogradation.

Changes in the properties of cooked rice under various cooking conditions were investigated. Waxy, low-, and high-amylose rice were subjected to treatment with different cooking temperatures (50, 70, 90 °C) for different cooking times (15, 30, 45 min). The results showed that cooking greatly increased the swelling behavior of waxy rice but decreased the swelling behavior and amylose leaching of low- and high-amylose rice. As the cooking temperature increased, rapidly digestible starch increased significantly for all rice products, whereas slowly digestible starch and resistant starch had a certain degree of reduction. Variation in the cooking time produced little effects on starch digestibility. Gelatinization temperature was positively correlated with temperature and time, whereas gelatinization enthalpy was negatively correlated with temperature and time. Pasting properties of all rice products decreased significantly as cooking temperature and time increased. The study showed that both cooking temperature and cooking time had significant impacts on the physicochemical properties and starch digestibility of waxy, low-, and high-amylose rice to various extents. Temperature had a more pronounced impact on the extent of change to the in vitro digestibility than did cooking time.

In this study, the starch structure and digestibility of glutinous rice cakes were investigated. The rice cakes were steamed or fried at different temperatures; the fried cakes were then separated into three parts—crust, middle, and core. Scanning electron microscopy and X-ray diffraction indicated that the starch structure in both the steamed and fried cakes was completely gelatinised and destroyed. As determined through differential scanning calorimetry, the starch structure became more seriously altered with increasing frying temperatures, with the crust tending to be more severely altered than the middle and core. The fried cakes contained 67.48%–73.64% of rapidly digestible starch, comparable to that in the steamed cakes, but higher than that in raw glutinous rice. Moreover, the fried cakes contained 19.89%–27.95% of slowly digestible starch, comparable to that in the steamed cakes and raw glutinous rice. However, the fried cakes 4.57%–6.57% of resistant starch—significantly lower than that in the steamed cakes and raw glutinous rice. Frying temperatures did not lead to significant changes among the three starch categories. The in vivo test results showed that steamed and fried glutinous rice cakes were both medium-glycaemic index foods.