Starch Fractions Research Articles

A novel method for obtaining high amylose starch fractions from debranched starch

High amylose starch shows wide applications in food and non-food-based industries. Traditional complex-precipitation approach for the amylose fractionation required a large volume of organic reagents and was possibly risky for food safety. The object of this work was to establish a novel method to obtain starch fractions rich in amylose from debranch starch through repeated short-term retrogradation and centrifugation. Four starch fractions were obtained with the amylose content of 52.08% (C1), 62.28% (C2), 63.58% (C3), and 64.74% (C4). The thermograms of samples displayed that multiple endothermic peaks were detected in C1 and C2 and only one endothermic peak with melting temperature over 120 °C were observed in C3 and C4, indicating their differences in retrogradation behavior. The chain length distribution results of sample exhibited that C1 and C2 contained more short chains (DP ≤ 24), while C3 and C4 consisted of mainly long chains (DP ≥ 25). Accordingly, the differences in fine structures could provide more choices for these fractionated high amylose starch to utilize in practical applications.

Application of the IR spectrometry method in the screening study of various oat species

BACKGROUND: The infrared reflection spectroscopy application method for rapid assessment of biochemical parameters in various types of oats is shown. On the basis of the biochemical data obtained in the laboratory of VIR, calibration models of protein, oil and starch content were constructed.
 AIM: The aim of the study is to develop an express method of near-infrared spectroscopy (NIRS) spectroscopy to determine the main biochemical parameters in oat seeds and to build calibration models for the MATRIX-I IR analyser to quantify the mass fraction of protein, oil and starch in oat seeds based on data obtained by traditional methods.
 MATERIALS AND METHODS: Biochemical quality indicators (protein, oil, starch) were studied on seeds of filmy oats (Avena sativa L.) grown in 20152016 in the North-Western Region of the Russian Federation. Calibration models for the determination of protein, oil and starch in oat seeds (98 samples, harvest 20142015) were developed for the MATRIX-I IR analyzer by Bruker Optics (Germany). Values obtained by traditional chemical methods of analysis were used to construct calibration models. Oat seed oil was determined by the Soxlet method, protein by the Kjeldahl method, starch by the Evers polarimetric method. All indicators were recalculated for dry weight.
 RESULTS AND CONCLUSION: The reliability of the developed models was checked by the results of protein, oil and starch determination in the seeds of the test batch according to the indicator of the calibration correctness. The data obtained using the calibration curve on the MATRIX-I device had no significant differences with the results of chemical studies. Therefore, calibration can be used for screening analysis for protein, oil and starch content in oat samples. This method allows you to save valuable material, increase labour productivity due to the speed of obtaining data, does not require reagents and is safe.

Spectroscopic techniques for elucidation of structural changes in temperate cowpea cultivars under germination: A useful tool for quality determination and industrial application

The present study investigated the molecular changes induced by germination in cowpea cultivars by spectroscopic techniques. The ATR FT-IR, Intrinsic fluorescence, and UV spectroscopic techniques revealed that germination shows alteration in cowpea cultivars. The ATR-FTIR showed slight differences in band intensities corresponding to carbohydrates, lipids, and protein regions at 700 to 4000 cm-1 wavenumbers. Starch order structure understanding their functionality showed a reduction of short-range ordered structures in Black cowpea flour and long ordered starch fraction in White cowpea flour under germination. The study quantified the degree of ordered starch and their alteration in amorphous/crystallinity nature concerning germination and cowpea cultivars. The secondary structures revealed a reduction of β-sheets and α-helix content, representing decreased ordered protein structures and their shifting into random coils and turn structures. The germinated flours showed decreased fluorescence intensities with the shift from 347 to 348, reflecting the redshifts due to decreased concentrations of fluorescent compounds during germination in cowpea flour. UV spectrum revealed a similar spectrum with an increase in absorption of cowpea flour under germination. The electrophoresis showed variations in the intensities of high (25 to 225 kDa) and low (19 to 10 kDa) molecular weight proteins in germinated cowpea cultivars than the native one. Overall, this study demonstrated the potential of ATR-FTIR, fluorescence and UV-based spectroscopy as non-destructive techniques to assess the alteration of pulses at the molecular level and structural changes under the germination process.

Phosphorylation and citration of normal corn starch by dry heating with phytic acid and citric acid

Normal corn starch was subjected to dry heating in the presence of phytic acid (PA, 2 %, starch basis) and citric acid (CA, 5 % and 10 %) for modification. Dual treatment with PA and CA induced structural and physicochemical changes in normal corn starch. Phosphorus concentration, degree of substitution, FTIR, and 31P NMR analyses confirmed esterification of starch by dry heating with PA and CA. Both phosphorylation and citration by esterification with PA and CA were observed in PA + 5CA starch, but high CA concentration inhibited covalent interaction between PA and starch in PA + 10CA starch. The degree of phosphorylation and citration resulted in different physicochemical properties in starch treated with PA and CA. The treatment with only PA did not change the crystalline regions of PA starch, but CA treatment induced the disruption of the crystalline structure of PA + 5CA and PA + 10CA starch. PA starch showed high solubility (46.41 %) and transmittance (90.51 %), but dual treatment of PA and CA induced significant decrease in solubility (3.23 %) and transmittance (2.18 %) of PA + 10CA starch. CA treatment increased the fraction of resistant starch in non-cooked (72.44 %) and cooked PA + 10CA starch (42.76 %). Therefore, dual treatment with PA and CA had potential to control physicochemical and functional properties of starch by phosphorylation and citration of starch.

Definition of starch components in foods by first-order kinetics to better understand their physical basis

Starch-based foods frequently contain different starch digestible fractions, with distinct digestion rates and locations in human upper gastrointestinal tract. Understanding the physical basis for these starch components is critical for developing foods with low glycemic index (GI) values. Conducting first-order kinetics analysis has been able to extract information on starch digestion properties, with solid physical basis. However, there is currently no clear procedure in terms of defining different starch fractions by first-order kinetics analysis. This review proposes that starch-based foods can be categorized as structurally homogenous or heterogenous starch systems by fitting their starch digestograms to the first-order kinetics model, which are characterized by a single set or multiple sets of digestion rate constants and the fractions remaining undigested at long times during in vitro digestion. In line with starch hierarchical structures, it helps understand the structural origins for different starch components in foods, which can ultimately help the development of functional foods with low GI. Procedure to identify the starch fractions in starch-based foods to better understand their physical basis. SF is single fraction. RDF represents rapidly digestible starch fraction, while SDF represents slowly digestible starch fraction. • Starch-based foods often contain multiple starch fractions. • These foods can be defined as structurally homogeneous or heterogenous foods. • This definition helps the understanding of physical basis for starch digestibility.

Bifidogenic property of enzymatically synthesized water-insoluble α-glucans with different α-1,6 branching ratio

Bifidobacteria uses insoluble resistant starch (RS) fractions as prebiotics in the colon, consequently improving human intestinal health. In this study, various α-1,6 linkage ratios of insoluble α-glucans were synthesized by amylosucrase from Neisseria polysaccharea and glycogen branching enzyme from Rhodothermus obamensis to investigate the effect of branching patterns on Bifidogenic property. Different ratios (0%–4%) of α-1,6 branched insoluble α-glucans with α-1,4 linked backbones were effectively synthesized. Additionally, the proportions of RS fraction in the synthesized α-glucans were 69.5%–81.9% after the cooking process, which are higher amounts than amylomaize VII (36.8%). As various Bifidobacteria used the insoluble branched α-glucans , the structure with 2.5% of 1,6 linkage showed the highest consumption yield, more than 70%, among all tested strains. Therefore, the insoluble α-glucans with different α-1,6 linkage ratios can be applied as prebiotic ingredients to modulate the Bifidobacterium species to enhance colon health and related outcomes. • Amylosucrase and glycogen branching enzyme was applied to synthesize α-glucans. •Insoluble α-glucans with different α-1,6 linkage ratios were successfully produced. •Insoluble branched α-glucans contain high amounts of resistant starch fraction. •Bifidobacterium species broadly used the insoluble α-glucans as prebiotics.

Effects of moisture content on digestible fragments and molecular structures of high amylose jackfruit starch prepared by improved extrusion cooking technology

The effects of different moisture contents on the digestible fragments and molecular structures of high amylose jackfruit starch were investigated. The digestible fragments and molecular structures of rapidly digestible starch, slowly digestible starch and resistant starch of high amylose jackfruit starch with different moisture contents prepared by improved extrusion cooking technology were analyzed. Decreasing the moisture content resulted in significant decrease in slowly digestible starch and resistant starch content (24.08% and 25.99%–17.59% and 16.60%), indicating that high amylose jackfruit starch with low moisture content was easier to digest. Compared to extruded control starches, the slowly digestible starch + resistant starch fraction and resistant starch samples exhibited higher gelatinization enthalpy, relative crystallinity, and short - range molecular order, but no significant difference was showed in gelatinization temperature. It was also found that the double helix degree, crystallinity and order degree of the extruded controls, slowly digestible starch + resistant starch fractions and resistant starch samples were increased with increasing moisture content, from 1.74 J/g, 1.52% and 0.207–9.52 J/g, 32.54% and 0.779, respectively. The above results were further supported by the microstructural and porosity analysis that the extruded samples were changed from coarser surface structure to more compact structure with increasing moisture content. All these results indicate that moisture content affects the digestible fragments and molecular structures of starch. Therefore, it can provide a theoretical basis for the modification of high amylose starch, especially for the modification of resistant starch. • High amylose jackfruit starch (HA-JFSS) were prepared by improved extrusion cooking technology. • Different moistures content affected the digestible fragment and molecular structure of HA-JFSS. • Decreasing moisture content improved the in vitro digestibility of extruded HA-JFSS. • High moisture content HA-JFSS showed higher double helix, long/short-range molecular order. • The analysis of SEM demonstrated the results of the DSC, XRD and FITR.

Photodegradation of biobased polymer blends in seawater: A major source of microplastics in the marine environment

IntroductionBiobased polymer blends have been recommended as an eco-friendly solution to abate plastic pollution in the environment. However, the formation of microplastics (MPs) by photodegradation of biobased polymer blends in the marine environment is still not well understood. In this study, we investigated the formation of MPs and the changes in the physicochemical properties of three types of biobased polymer blends after photodegradation in seawater.MethodsThe investigated materials included non-biodegradable polyethylene/ thermoplastic starch blends (PE/TPS) and polypropylene/thermoplastic starch blends (PP/TPS), as well as biodegradable polylactic acid/poly (butylene adipate-co-terephthalate)/thermoplastic starch blends (PLA/PBAT/TPS). The control groups were the corresponding neat polymers, including polyethylene (PE), polypropylene (PP), and polylactic acid (PLA).ResultsThe size distribution of the pristine and aged MPs indicated that the polymer blends were more likely to produce small-sized particles after photodegradation due to their poorer mechanical properties and lower resistance to UV irradiation than the neat polymers. Noticeable surface morphology alterations, including cracks, holes, and pits, were observed for polymer blends after photodegradation, while neat polymers were relatively resistant. After photodegradation, the attenuated total reflection Fourier transformed infrared spectroscopy (ATR-FTIR) spectrum of the polymer blends showed a significant decrease in the characteristic bands of thermoplastic starch (TPS), indicating depletion of their starch fractions. The C1s spectra of the polymer blends demonstrated that the aged MPs contained fewer -OH groups than the pristine MPs, further confirming the photodegradation of TPS. The molecular weight distribution curve of the polymer blends shifted significantly towards low molecular weight, suggesting the occurrence of chain scission during photodegradation. These results indicate that the polymer blends have a higher degree of photodegradation than neat polymers, and thereby generate more small-sized MPs than neat polymers. Photodegradation caused changes in the contact angle and surface charge of MPs derived from biobased polymer blends, which may affect the vector effects of MPs on any coexisting pollutants.DiscussionIn summary, polymer blends may pose a higher risk to the marine environment than neat polymers, and caution should be taken in promoting biobased polymer blends.

Changes in Starch In Vitro Digestibility and Properties of Cassava Flour Due to Pulsed Electric Field Processing.

The research aimed to investigate the effect of pulsed electric field (PEF) treatment on cassava flour at mild intensities (1, 2, and 4 kV/cm) combined with elevated levels of specific energy input (250-500 kJ/kg). Influences on starch digestibility, morphological characteristics, birefringence, short-range order and thermal properties were evaluated. Application of PEF at energy input no greater than 250 kJ/kg had negligible influence on the different starch digestion fractions of cassava flour but raised the rapidly digestible starch fraction at a combined electric field strength >1 kV/cm and energy input >350 kJ/kg. Morphological evaluation revealed that at this PEF combination, cassava starch's external structure was consistently altered with swelling and disintegration, albeit some granules remained intact. Consequently, this led to disruption in the internal crystalline structure, supported by progressive loss of birefringence and significantly lower absorbance ratio at 1047/1022 cm-1. These physical and microstructural changes of the inherent starch promoted the shift in gelatinization temperatures to a higher temperature and reduced the gelatinization enthalpy. The study demonstrated that PEF can be utilized to change the starch fraction of cassava flour, which is driven by electric field strength and specific energy input, causing changes in the starch-related properties leading to increased digestibility.

A procedure for determining the number and pattern of digestible starch fractions in multiphasic food digestograms.

Plant-based foods are frequently heterogenous systems, containing multiple starch fractions with distinct digestion rate constants. An unbiased determination of the number and digestion pattern of these fractions is a prerequisite for understanding the digestive characteristics of food. A non-linear least-squares procedure based on a conditional selection of simple first-order kinetics or a combination of parallel and sequential kinetics models was developed. The procedure gave robust results fitting manually generated data, and was applied to in vitro experimental digestion data of retrograded rice starches. By correlating fitting parameters with starch structural parameters, it showed that rice starches with a lower amylose content, longer amylose chains, and amylopectin intermediate chains had more digestible starch fractions after long-term retrogradation. This procedure enables the structural basis of starch digestibility and the development of food products with slow starch digestibility to be better understood. © 2022 Society of Chemical Industry.

Effect of different starch contents on physical, morphological, mechanical, barrier, and biodegradation properties of tapioca starch and poly(butylene adipate‐co‐terephthalate) blend film

AbstractStudy on degradation behaviors of biodegradable poly(butylene adipate‐co‐terephthalate) (PBAT) blended with different compositions of thermoplastic starch (TPS) under soil burial and natural weathering environments is vital in order to predict the product service‐life and planning for in situ biodegradation after product disposal. In this article, different compositions of TPS (0%, 20%, 40%, 50%, and 60%) were compounded with PBAT using single screw extruder. The samples were characterized for their tensile properties, fractured surface morphology, water barrier and surface hydrophorbicity properties in order to investigate the effect of starch fractions in PBAT blends. The degradation behavior under natural weathering and soil burial conditions was also determined during the 9 months duration by observing the change of physical appearance, weight loss, surface morphology, chemical structural, and tensile properties. The findings showed that the addition of TPS (20%, 40%, 50%, and 60%) had led to a reduction in tensile strength (41.47%, 60.53%, 63.43%, and 68.53%), and reduction in elongation at break (42.92%, 92.1%, 92.23%, and 93.22%, respectively) and water barrier properties. The findings also showed that there were distinct degradation behavior under both conditions. Upon exposure to natural weathering, photodegradation and Norrish type I & II occurred whereas under the soil burial condition, hydrolytic, and enzymatic degradation take places. Sample with the highest starch contents underwent the highest weight loss and reduction in tensile properties under both environments. The findings in this study are useful in order to investigate the feasibility of PBAT/Tapioca starch blends for biodegradable plastic film for various industrial applications especially in packaging and agricultural mulch.

Effects of Composition and Strength of Wheat Gluten on Starch Structure, Digestion Properties and the Underlying Mechanism.

To understand the effect of gluten on starch digestion characteristics, the structural characteristics of protein, starch, and starch digestion attributes were explored by using flours of four wheat near-isogenic lines. Protein and starch fractions from the four flours were used to form so-called recombinant flours where glutenin and gliadin protein fractions, in different ratios, were combined with starch and heated in a water slurry at 80 °C for 5 min. We found that starch digestibility of the recombinant flours could be reproducibly modified by altering the long- and short-range molecular order of starch through varying the attributes of the gluten protein by virtue of the gluten strength as well as the proportions of glutenin and gliadins. The gluten composition changes of strong-gluten flour did not improve the starch digestion resistibility, however, for the moderate- and weak-gluten flours, the proportional increase of glutenin improved the resistance of starch to digestion through the increased long- and short-range molecular order of starch. The resistance of starch to digestion could also be enhanced with increasing gliadin, and was associated with the modified short-range molecular order of starch. We propose that flour mixtures can be optimized for specified product quality by manipulating the amounts of both gliadin and glutenin.

Understanding the Mechanism of How Pulsed Electric Fields Treatment Affects the Digestibility and Characteristics of Starch in Oat Flour

The objective of this study was to evaluate the effect of pulsed electric fields (PEF) on the in vitro starch digestibility properties of oat flour. A wide range of PEF process intensity was investigated (electric field strength between 2.1 and 4.5 kV/cm and specific energy inputs between 52 and 438 kJ/kg using 20 μs square wave bipolar pulse at 100 Hz). The results revealed that PEF applied at a high electric field strength and energy <216 kJ/kg was favourable in slowing down the rate of starch digestibility (by 48%) during in vitro gastrointestinal digestion. This is accompanied by a significant decrease (from 15% to 7–10%) in the proportion of rapidly digestible starch (RDS) and a significant increase (from 77% to 84–85%) in resistant starch (RS) fraction. The application of PEF at energy level >421 kJ/kg at any field strength intensities raised the RDS (from 15% to 19–20%), but the rate of starch digestion was not affected (maintained at 3.3–3.7 × 10−2 min−1 vs. untreated at 3.8 × 10−2 min−1). Further analysis of the structure, particle size, and thermal stability of PEF-treated oat flour through fractionation into three distinct flour segments revealed that PEF could cause major modifications in the particle size, damage and aggregation of starch granules, and destruction of the long- and short-range ordered structures of starch. Data gathered in this study indicate that PEF treatment can be a reliable strategy to modulate the in vitro starch digestibility of oat flour, either by reasonably slowing down the digestion rate or enabling a slightly higher amount of starch to be readily accessible by digestive enzymes without affecting the digestion rate.

Effect of High Hydrostatic Pressure Processing on Starch Properties of Cassava Flour

The aim of this study was to utilize high-pressure processing (HPP) to modify cassava flour through altering the starch components. Specifically, the effect of HPP processing variables, i.e., pressure (0.10 or untreated, 300, 400, 500, and 600 MPa), flour concentration (FC; 10, 20, and 30%), and holding time (HT; 10 and 30 min) on starch-related properties was studied. Microstructural integrity, thermal properties, and starch susceptibility to digestive enzymes were determined. A three-way ANOVA was performed to identify the interaction effect between these process variables. In general, 600 MPa consistently transformed the crystalline starch into an amorphous one. HPP-induced gelatinization led to enlarged starches with loss of birefringence, reduced relative crystallinity percentage, and changes in short-range order. The three-way interaction between the process variables was evident in the significant progressive rise in onset gelatinization temperature and degree of gelatinization, and the decline in gelatinization enthalpy from 500 to 600 MPa with decreasing FC and increasing HT. These changes caused an increased percentage of rapidly digestible starch and decreased resistant starch fraction. Overall, this study’s results imply the possibility of using HPP to modify the starch component in cassava flour and potentially create flours with varying levels of functionalities.

Effect of starch and fibre on faba bean protein gel characteristics

Faba bean is a promising alternative to soybean for production of protein-rich plant-based foods. Increased understanding of the gelling behaviour of non-soy legumes can facilitate development of novel plant-based foods based on other legumes, such as faba bean. A mixture design was used in this study to evaluate the effect of different proportions of protein, starch and fibre fractions extracted from faba beans on gelation properties, texture and microstructure of the resulting gels. Large deformation properties, in terms of fracture stress and fracture strain, decreased as fibre and/or starch replaced protein. In contrast, Young's modulus and storage modulus increased with substitution of the protein. Light microscopy revealed that for all gels, protein remained the continuous phase within the region studied (65–100% protein fraction, 0–35% starch fraction, 0–10% fibre fraction in total flour added). Swollen and deformed starch granules were distributed throughout the mixed gels with added starch. Leaked amylose aggregated on starch and fibre surfaces and in small cavities (<1 μm) throughout the protein network. No clear difference between samples in protein network structure was observed by scanning electron microscopy. The reduction in large deformation properties was tentatively attributed to inhomogeneities created by the added starch and fibre. The increase in small deformation properties was hypothesised to be affected by water adsorption and moisture stability through the starch and fibre, increasing the effective protein concentration in the surrounding matrix and enhancing the protein network, or potentially by starch granules and fibre particles acting as active fillers reinforcing the gel structure. • Partly replacing protein with starch and/or fibre reduce the fracture stress. • Partly replacing protein with starch and/or fibre increase the storage modulus. • Addition of starch and/or fibre did not largely alter the protein network structure.

In vitro starch digestibility and estimation of glycemic index in algae‐based couscous

SummaryEnrichment of foods by algae or their derived nutrients is of a great interest to enhance nutritional properties leading to health promotion and disease prevention by a sustainable way. In this context, five Chlorella vulgaris and one micro‐macroalgae blend (Algaessence®) with different biochemical compositions were used (6%) in the formulation of couscous in an attempt to modulate glycemic response and enhance functional aspect. Phytochemicals, such as carotenoids and phenolics were retained to a higher extent in algae‐couscous being the highest (5.58 mg GAE/g and 1.05 mg/g, respectively) in the couscous formulated with autotrophic Chlorella (designated as Organic). Starch fractions and in vitro starch digestion of the products were determined. The highest starch content was found in control couscous (73.83%) which resulted in higher digestible starch (70.55%). The kinetic constant, designative of the hydrolysis rate in the early stage, was the lowest in algae‐couscous (0.022). The lowest hydrolysis index of 70.27% and 71.71% were observed in Organic and White couscous (heterotrophic), respectively; leading to lower glycemic index of 78.21% (Organic) and 79.00% (White). The obtained results evidence the potential use of algae in the formulation of value‐added food products designated for controlled diets.

Non-conventional starch from cubio tuber (Tropaeolum tuberosum): Physicochemical, structural, morphological, thermal characterization and the evaluation of its potential as a packaging material

This work aimed to characterize the physicochemical, structural, morphological, and thermal properties of a non-conventional starch obtained from cubio (Tropaeolum tuberosum), as well as to evaluate the potential use of this native Andean tuber in the preparation of biodegradable packaging. The cubio starch (CUS) showed an intermediated apparent amylose content (31.2 %) accompanied by a high CIE whiteness index (90.8). About the morphology and particle size, the CUS exhibited irregular oval and round shapes and a smooth surface with a mean particle diameter of 14.04 ± 0.1 μm. Although it showed good stability regarding pasting properties, the final viscosity was low. Native CUS exhibits a typical B-type diffraction structure, with a relative crystallinity of 16 %. The resistant starch (RS) fraction of the CUS was 94 %, indicating a low susceptibility to enzymatic hydrolysis. The thermal analysis demonstrated that the CUS showed good thermal stability. Additionally, the films prepared using CUS as raw material showed continuous surfaces without porosities, good thermal stability, and high transparency. The results of this work demonstrate the industrial potential of the CUS as it presents characteristics comparable to commercial potato starch.

Evaluation of various varieties of peas as raw material for deep processing

The article provides an overview of the criteria for choosing pea varieties to evaluate economically valuable traits. For the effective use of peas as raw materials for deep processing, two directions can be considered: a joint increase in the content of protein and starch or the choice of varieties with the required indicators. The results of laboratory studies of processing for starch and protein isolate of 37 variety samples of peas from the collection of the Federal State Budgetary Scientific Institution «Federal Scientific Center of Legumes and Groat Crops» are presented. As evaluation criteria determining high technological properties, providing the most complete extraction of starch and protein isolate there have been selected coefficients of extraction of these components. When selecting a variety of peas, it is also necessary to consider the physicochemical properties of starch, which depend on the mass fraction of amylose. According to the results obtained, the most promising varieties for the processing of grain into starch and protein isolate are Orlovchanin, Alla, Rodnik, Sibirsky 1, Pharaon, Jaguar, Sophia. The most efficient extraction of the main processed products ‒ protein isolate and starch is established for the variety Alla, protein extraction coefficient 81.2 %, starch 90.6 %. Among the wrinkled pea varieties for industrial processing, the Amius 1241 breeding line is the most interesting, with protein isolate and starch extraction coefficients of 70.3 and 69.1 % and a mass fraction of amylose in starch of 81.5 %. It is found that the mass fraction of starch and protein in pea grains does not correlate with the extraction coefficients of protein and starch isolate during processing by two-stage extraction of protein from pea flour using the alkaline method. When processing wrinkled pea varieties, there are difficulties in separating the starch and residual protein undissolved in alkaline medium, since these pea varieties are found to have complex starch granules, which are easily crushed into small irregular and polygonal granules. In smooth pea varieties, the starch granules are oval in shape with a high percentage of large size and therefore there are no problems with separation of the starch-protein suspension. The dependence of viscosity of 3.0 % pea starch paste on the mass fraction of amylose in pea starch has been determined. The choice of pea variety for processing makes it possible to produce starch that has lifetime modification, i.e., that has the required physical and chemical properties and resistance. In addition, depending on the choice of pea variety, it is possible to predict the yield of isolate and protein concentrate.

Influence of sprouted oat flour substitution on the texture and in vitro starch digestibility of wheat bread.

The aim of this study was to investigate the effect of sprouted oats substitutions on the in vitro digestibility of starch in the wheat bread. The physical and nutritional quality of wheat bread enriched with 20% sprouted oat flour was compared. The polyphenols and γ-aminobutyric acid increased, while the content of starch and β-glucan in the mixed bread was gradually decreased. The specific volume of mixed bread reached the maximum with a 19.79% reduction of area fraction and a 31.36% increase cell density when sprouting for 72h. Two digestible starch fractions with different digestion rates were observed from the LOS-CPS fitted starch digestograms. The microstructure revealed that large type A wheat starch was gelatinized after baking, whereas small type B wheat starch and oat starch were wrapped in protein-β-glucan complexes. This study suggests that properly sprouting has the potential to obtain nutritional bread with low starch digestibility.

Research Note: Amylase supplementation improves starch and amino acids digestibility of faba bean for broilers

This study aimed to investigate the effect of amylase on the nutritional value and nitrogen-corrected apparent metabolizable energy (AMEN) of faba bean (FB) seeds in broiler chicken nutrition. The study was conducted on a total of 84, one-day-old male broiler chickens (Ross 308). The birds were fed a reference corn-soybean meal diet form d 1 to 16, and they were divided into three groups (1st day). The first group (1) was fed the same reference diet as in the first part, whereas 50% of the reference diet was replaced by FB seeds in experimental groups (2 and 3). Group 3 was supplemented with amylase, which contained 0.14 g/kg dry matter (DM). At the end of the study period, excreta and digesta samples were collected from all groups to estimate the nutritional value. Some fraction of starch found in the seeds was part of starch which is resistant to digestion (143.9 g/kg DM). The addition of exogenous amylase to the diet increased the apparent ileal digestibility of DM, CP, and starch in FB seeds. The AMEN value increased as a result of enzyme addition (P < 0.05). The group 3 showed higher apparent ileal digestibility of essential amino acids (Lys, Leu, Phe, His) as well as nonessential amino acids (Tyr, Ala, Pro) in FB seeds. It could be concluded that FB seeds supplemented with exogenous amylase have a greater nutrition value for broiler chickens.