Effect of hydrothermal treatment of runner bean (Phaseolus coccineus) seeds and starch isolation on starch digestibility

The study investigated the effect of traditional soaking and cooking, storage after cooking and freezing (? 18 °C, 21 days) and autoclaving of two varieties of runner bean on starch digestibility. Results achieved were compared with digestibility of isolated starch subjected to similar treatments. The digestibility of native starch from Nata var. seeds was lower after isolation than in raw flour. This starch was characterized by a higher content of fat and lower values of swelling power (SP) and amylose leaching (AML). After the thermal treatment, a significantly higher content of rapidly digestible starch (RDS) was observed both in seeds and starch. It was accompanied by reduced contents of resistant starch (RS) and slowly digestible starch (SDS). In flours from cooked seeds, the content of RDS was observed to be higher than in flours from autoclaved seeds, despite similar changes in contents of other constituents (ash and protein). It was probably due to better starch gelatinization owing to the long-lasting soaking of seeds. This resulted in a greater decrease of amylose content of starch compared to the other flours. Differences in SP, AML and thermal properties between starches isolated from two bean varieties had no influence on their digestibility after cooking. The storage of starch pastes at a temperature of ? 18 °C, unlike that of seeds, resulted in a significant increase in RS content, which shows the importance of other flour components in the process of starch retrogradation.     

Nutritional value of broad bean seeds. Part 3: Changes of dietary fibre and starch in the production of commercial flours

We report on the impact of flour production from small- and large-seed varieties of broad bean on the quantitative and qualitative distribution of dietary fibre and starch. The experimental material consisted of the seeds of small-seed varieties of broad bean: Gobik and Goral, large-seed varieties of broad bean: Windsor Bialy and Bartom, and pea seeds of Albatros, Karat and Miko varieties (for comparison). The seeds were at full physiological maturity. Soaking and hydrothermal processing were shown to cause multidirectional, statistically significant changes in dietary fibre and starch, depending on both parameters of the process and type of the seeds. The flours of both small-seed broad bean varieties contained 20.15%-28.31%, flours of the large-seed broad bean 23.10%-27.50%, and those from pea seeds 20.13%-22.81% total dietary fibre. Attention should be paid to the considerable, approximately 2-fold increase in the soluble dietary fibre (SDF) content, compared to the raw material. The processing of seeds caused significant changes also with reference to starch. The most considerable changes were observed when the variant with the longest times of soaking (18 h) and heating (45 min) was applied. In the broad bean flours, the content of analytically available starch decreased by 22.94-30.60% and its digestibility was observed to decrease up to 30.25%. The pea flours, however, were characterised by an increased concentration of both forms of starch, especially significant for the digestible starch. The calculated content of resistant starch (RS) differentiated, to a high extent, the flours obtained. Under the same processing conditions, the flours of small-seed Gobik and Goral varieties of broad bean were characterised by a significantly higher RS content than those obtained from the large-seed varieties. A decrease in the starch digestibility rate index (SDRI) values, especially high for the small-seed varieties, should also be emphasised. The results obtained indicate that the nutritional value of flours can be determined by controlled processing parameters.     

Nutritional quality of legume seeds as affected by some physical treatments, Part 1: Protein quality evaluation

The effect of water soaking, boiling, roasting, microwave cooking, autoclaving, fermentation and micronization on the nutritional quality of cowpea, pea and kidney bean was investigated. Pea seeds showed the highest crude fat, crude fiber and the lowest moisture contents while kidney bean had the lowest crude fat and the highest crude protein and ash contents. Glu and Asp were the main amino acids in all legumes while Cys and Met contents were the lowest. The protein efficiency ratio (PER), protein chemical score (CS) and the essential amino acid index (EAAI) of raw seeds ranged from 2.15 to 2.95, 39.07 to 68.30, and 55.49 to 62.84, respectively. Soaking, boiling, microwave cooking and autoclaving increased the total essential amino acids in all samples. Furthermore, raw and treated samples showed higher Lys content than the reference protein. Autoclaving was the most effective in improving protein quality followed by micronization, microwave cooking and fermentation. In addition, in vitro protein digestibility was improved after soaking, boiling, microwave cooking, autoclaving and fermentation but was reduced after roasting and micronization.     

Chemical composition,in vitro starch digestibility and amino acid analysis of a underexplored kidney bean (Phaseolus vulgaris. L.) grown in Chongqing,China

Chemical composition, mineral analysis, in vitro starch digestibility, and amino acid analysis of a kidney bean (Phaseolus vulgaris. L.), grown in Chongqing, China, were carried out in 2011. The results showed that the bean flour contained low reducing sugar (0.79%) and fat (2.72%), but high protein (24.8%) and starch (44.84%). Mineral analysis indicated high Mg and Ca contents with low Na/K ratio (0.04). The proportions of rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) were 39.64%, 41.46% and 18.90% respectively. And the variation in their proportions, along with prolonged heating time, showed increase in RDS, and decrease in SDS and RS, but the SDS + RS amount can still account for major parts (51.63%) of the total starch after a 90‐min pre‐cooking. Comparing the amino acid contents of the bean sample with recommended profile FAO/WHO/UNU (1985), the results fulfil the standard except threonine and lysine, whose contents are slightly lower than the requirements (0.93 and 0.85).     

In vitro starch digestibility,expected glycemic index,and thermal and pasting properties of flours from pea,lentil and chickpea cultivars

In vitro starch digestibility, expected glycemic index (eGI), and thermal and pasting properties of flours from pea, lentil and chickpea grown in Canada under identical environmental conditions were investigated. The protein content and gelatinization transition temperatures of lentil flour were higher than those of pea and chickpea flours. Chickpea flour showed a lower amylose content (10.8–13.5%) but higher free lipid content (6.5–7.1%) and amylose–lipid complex melting enthalpy (0.7–0.8 J/g). Significant differences among cultivars within the same species were observed with respect to swelling power, gelatinization properties, pasting properties and in vitro starch digestibility, especially chickpea flour from desi (Myles) and kabuli type (FLIP 97-101C and 97-Indian2-11). Lentil flour was hydrolyzed more slowly and to a lesser extent than pea and chickpea flours. The amount of slowly digestible starch (SDS) in chickpea flour was the highest among the pulse flours, but the resistant starch (RS) content was the lowest. The eGI of lentil flour was the lowest among the pulse flours.     

加工方法对红小豆碳水化合物消化速度的影响

运用体外模拟消化方法探讨了不同加工方法对红小豆中碳水化合物的消化速度和淀粉组分中快速消化淀粉(RDS)、慢速消化淀粉(SDS)和抗性淀粉(RS)含量的影响。结果表明,烹调压力和颗粒大小对红小豆中淀粉消化率及淀粉组分有较大影响。高压烹调水解率高于常压烹调,烹调前粉碎处理显著提高RDS和淀粉水解指数(SDI),但烹调压力对豆粉的消化速度指标无影响;煮熟的豆在冷藏前后碳水化合物水解率的差异不显著。     

藜麦发芽过程中蛋白质与皂苷及淀粉消化特性的变化规律

发芽是改善谷物质构及其营养价值的一种高效的加工方式。本文研究了藜麦发芽过程中蛋白质与皂苷及淀粉消化特性的变化规律。结果显示,发芽显著地提高了藜麦中粗蛋白和可溶性蛋白含量,分别增加了5.38%和17.55%。随着发芽时间不断增加,藜麦总淀粉、直链淀粉及支链淀粉含量分别减少25.95%、4.86%和29.53%,而还原糖含量增加了26.60%。发芽处理显著改善了藜麦种子的淀粉消化性能。发芽前藜麦种子中快消化淀粉、慢消化淀粉及抗性淀粉的百分含量分别为38.45%、43.64%和17.90%。发芽48h后,快消化淀粉的百分含量显著地增加至53.46%,而慢消化淀粉及抗性淀粉的百分含量分别下降至40.42%和6.11%。此外,发芽后藜麦种子中总皂苷含量显著增加了16.46%。研究表明,发芽的藜麦种子含有更好的营养价值和消化性能,可以用于加工功能性食品,促进人体健康。     

Impact of Process Conditions on Digestibility of Pea Starch

This study investigated how process conditions affect the digestibility of pea starch from pea starch powder (PSP). The factors considered were resistant starch (RS), slow digestible starch (SDS) and rapidly digestible starch (RDS) content. The examined five process factors were: material/water ratio, cooking temperature, cooking time, soaking time, and heat dehydration time. Changes in process conditions mainly altered the content of RS and SDS. Analysis with Sephadex G-200 chromatography and differential scanning calorimetry revealed that RS was mainly from retrograded amylose and amylopectin, while SDS and RDS were mainly derived from amylopectin.     

压力烹调对五种食材中淀粉消化性的影响

目的:探讨不同烹调方法对红小豆、莲子、山药片、芡实、薏米5种富含淀粉的保健食材的碳水化合物消化特性的影响,为科学食用传统食材提供依据。方法:体外模拟消化方法测定各时间点的水解率、快消化淀粉、慢消化淀粉和抗性淀粉等指标。结果:压力烹调显著影响样品的水解速率和淀粉类型,水解指数增大,快消化淀粉含量增加,抗性淀粉含量减少。但所有样品的预期血糖负荷均显著低于粳米样品。红小豆和莲子经过压力烹调仍保持低消化速度和低EGL特性。结论:压力烹调对提高难烹煮碳水化合物消化率有利,需要控制血糖的人可以通过选择慢消化食材和烹调参数来控制淀粉类型和EGL的变化。     

Effect of various processing techniques on digestibility of starch in Red kidney bean (Phaseolus vulgaris) and two varieties of peas (Pisum sativum)

The effect of common domestic processing methods, such as splitting, soaking, boiling and pressure-cooking on the nutritionally significant starch fractions such as rapidly and slowly digestible starches (RDS and SDS), resistant starch (RS) and total starch (TS) in two legumes, Red kidney bean (Phaseolus vulgaris) and Yellow and Green peas (Pisum sativum) were studied. The legumes had comparatively high amount (>30%, dry basis) of RS. Soaking of all legumes resulted in reduced starch fractions, possibly due to leaching of soluble fractions. Ordinary cooking of soaked as well as unsoaked seeds led to a significant (P < 0.01) decrease in RS and increase in RDS, SDS and TS. Pressure-cooking led to even greater reduction in RS and a greater increase in RDS. Cooking of legumes gelatinizes the starch and opens up the starch structure which makes them vulnerable to α-amylase hydrolysis. Splitting of legumes markedly affects the digestibility as well as RS content of raw as well as processed legumes indicating that the seed coat plays a key role in the digestibility of starches in these seeds. Overall, the enzyme resistant starch fraction of legumes was rendered more digestible by all the domestic cooking methods used.     

Effect of debranching and heat‐moisture treatment on the properties of Thai rice flours

High and low amylose Thai rice flours (KC and ML, respectively) were used in this work, to increase the resistant starch (RS) content in the flour. Pullulanase debranching followed by heat‐moisture treatment (DHMT) altered the pasting properties, which increased the shear stability to the flours. The gelatinisation temperature determined by DSC was increased and the more retrogradation occurred in treated flour compared to the native flour. The SEM observation showed that the treatment did not change the morphology of the granules in both flours. The slowly digestible starch (SDS) content in DHMT KC was higher than in the native KC. The RS content in the treated ML flour was increased to 18.31% from 11.59% in native flour. These concluded that the treatment affected the digestibility, while maintaining the granular structure.     

大米淀粉凝胶储藏过程中消化特性的变化

对大米淀粉凝胶储藏过程中消化特性的变化进行了研究，研究结果表明：在储藏早期，直链含量高的大米淀粉凝胶，随着直链凝皎网络的形成和稳定，淀粉体系中慢消化性淀粉和抗性淀粉含量显著增加，表明直链三维凝胶网络对酶有较强抗性。在后期的储藏过程中，随着储藏时间的延长，大米淀粉体系中慢消化性淀粉含量逐步增加，慢消化性淀粉含量增加的主要原因是由于支链淀粉的重结晶所引起。     

黔江肾豆碳水化合物组成及淀粉营养特性研究

以黔江肾豆为材料,对其碳水化合物组成和淀粉营养特性进行了研究。结果显示,肾豆富含碳水化合物(57.25±0.41)%,其中淀粉和粗纤维质量分数分别为(48.16±0.59)%和(3.59±0.11)%,表明肾豆是食物能量和膳食纤维的重要来源。淀粉直/支比0.63,较豌豆和部分绿豆高;肾豆淀粉消化特性分析显示慢消化淀粉(SDS)和抗性淀粉(RS)占比60.24%,可在混合膳食中起降低膳食整体碳水化合物消化速率的作用,对于慢性疾病如心血管等疾病和糖尿病的预防有益。体外血糖指数(GI)分析显示肾豆淀粉GI=88.5,为高GI;肾豆全粉GI=67.2,为中GI食品,肾豆全粉GI值低于肾豆淀粉,与其含蛋白质、纤维素、单宁、植酸和脂肪等成分有关。因此,食用全豆可减慢消化。黔江肾豆淀粉是制备粉丝、粉皮等深加工淀粉食品的良好淀粉来源。     

Nutritional composition and antinutritional factors of mung bean seeds (Phaseolus aureus) as affected by some home traditional processes

The effects of some domestic traditional processes, such as dehulling, soaking, germination, boiling, autoclaving and microwave cooking, on the nutritional composition and antinutritional factors of mung bean seeds were studied. Germination and cooking processes caused significant (p<0.05) decreases in fat, carbohydrate fractions, antinutritional factors and total ash contents. All processes decreased the concentrations of lysine, tryptophan, threonine and sulfur-containing amino acids. However, all treatments were higher in total aromatic amino acids, leucine, isoleucine and valine contents than the FAO/WHO reference. Dehulling, soaking and germination processes were less effective than cooking processes in reducing trypsin inhibitor, tannins and hemagglutinin activity contents. Also, germination was more effective in reducing phytic acid, stachyose and raffinose. Germination resulted in a greater retention of all minerals compared to other processes. In vitro protein digestibility and protein efficiency ratio were improved by all processes. The chemical score and limiting amino acids of mung bean subjected to the various processes varied considerably, depending on the type of process.     

Effect of processing and storage time on in vitro digestibility and resistant starch content of two bean (Phaseolus vulgaris L) varieties

Seeds from two commercial bean varieties were cooked and stored for different times and analysed for chemical composition and in vitro starch digestibility. Parallel portions of cooked seeds were dried at 55 °C, milled and stored as flours. In general, protein and ash contents in both samples did not change with storage time, but statistical differences were shown between the two varieties (p < 0.05). Available starch (AS) contents in flours from the ‘negro’ variety did not change (p < 0.05) with storage time and, in general, were higher than in ‘flor de mayo’ samples, whose AS levels decreased during storage. The lower AS in ‘flor de mayo’ flour could be the consequence of formation of resistant starch due to retrogradation. Samples of whole ‘negro’ seeds did not show differences in AS content at 0, 24 and 48 h of storage compared with the corresponding flours, but at 72 and 96 h the AS increased in the whole samples. ‘Flor de mayo’ showed a similar pattern in flour and whole samples, with slightly higher values in the whole seeds. In general, total resistant starch (RS) content in the two varieties was higher in the flours than in ‘whole’ seeds, a fact that is not easy to explain at present. ‘Negro’ flour presented an RS content around 65.0 g kg^?1, and approximately 55.0 g kg^?1 was recorded in ‘flor de mayo’, with slight changes when storage time increased. Whole ‘flor de mayo’ showed significant levels of the retrograded portion of resistant starch (RRS), which did not change with storage time (p < 0.05). However, values were lower than in the flours. A pattern similar to that of the ‘negro’ variety was obtained for ‘flor de mayo’, since the flour exhibited higher amounts of RRS; however, in this variety, the RRS content in ‘whole’ samples decreased after prolonged storage. Flours presented higher amylolysis rates than whole samples, and the ease of digestion increased with storage time. Copyright © 2003 Society of Chemical Industry     

Reducing the glycaemic index and increasing the slowly digestible starch content in gluten‐free cereal‐based foods: a review

Commercially available gluten‐free (GF) cereal‐based foods are generally characterised by a lower nutritional quality than their gluten‐containing counterparts, relatively lower resistant starch (RS) content, along with higher glycaemic index (GI) often being reported. To overcome this nutritional imbalance, extensive research has been conducted to investigate the preparation of a new generation of staple GF products. This review reported the main strategies currently adopted in GF cereal‐based food recipes to formulate products with overall slowly digestible starch properties. They are mainly obtained by the utilisation of alternative ingredients to be incorporated into standard food formulation (including native starch and GF flours) or by technological treatments that may contribute to impact starch digestibility. Considering data from in vitro digestion trials, indications suggested that, aiming to obtain a RS content of about 5% (dry weight) and lowering the in vitro GI values, the minimum high amylose starch (amylose >60%) replacement level in GF bread and cookie formulations should be in the order of 20% by weight of total flours. Overall, with respect to un‐substituted GF foods, two‐ to three‐times higher RS contents, along with a parallel in vitro GI decrease (up to ?50%), were obtained for GF pasta and ready‐to‐eat snacks enriched with legume flours at inclusion levels from 40% to 100% by weight of total flours. The use of flours from pseudocereals (e.g., quinoa, amaranth and buckwheat) with and without sourdough did not always guarantee favourably slowly digestible starch GF foods.     

Gluten‐free spaghetti made with chickpea,unripe plantain and maize flours: functional and chemical properties and starch digestibility

The development of gluten‐free spaghetti with a low amount of glycaemic carbohydrate was investigated. The goal of this study was to determine the chemical composition, cooking quality and starch digestibility of gluten‐free spaghetti elaborated with mixtures of chickpea, unripe plantain and maize flours. The gluten‐free spaghetti presented a higher protein, fat and ash content than the control semolina spaghetti. The solid loss among all the gluten‐free spaghetti was in the range of 10.04–10.91% and not significantly different from each other. These values were almost at the limit of acceptability to be considered as good cooking quality. Total starch in the gluten‐free spaghetti was lower than the control spaghetti. The lower available starch (AS) and higher resistant starch contents in the gluten‐free spaghetti were associated with their lower rate of hydrolysis and predicted glycaemic index. There is a potential for developing gluten‐free spaghetti with reduced amount of glycaemic carbohydrates from unconventional food ingredients such as chickpea, unripe plantain and maize flours.     

Starch and protein digestibility of newly released moth bean cultivars: Effect of soaking, dehulling, germination and pressure cooking

Effect of soaking (12 h), soaking (12 h) dehulling, germination (60 h) and pressure cooking on starch and protein digestibility of four varieties of moth bean, one Local commonly used by the farmers of the area and three newly released high yielding varieties, Jwala, RMO 225 and RMO 257, was studied. The starch digestibility of raw unprocessed moth bean cultivars differed significantly (P < 0.05) from 25.4-28.2 mg maltose released/g flour being the highest and lowest in RMO 257 and RMO 225, respectively. The protein digestibility differed significantly from 70.3-74.6 per cent among all the unprocessed varieties of moth bean. All the processing treatments namely soaking, dehulling, germination and pressure cooking brought about appreciable enhancement in protein digestibility (1-19%) over the control and starch digestibility (19-115%) of all the four moth bean cultivars. However, out of all the processing treatments, germination (60 h) of soaked seeds (12 h) was the most effective in bringing about improvement in digestibility of starch and protein followed by dehulling and soaking (12 h).     

EFFECT OF PROCESSING ON NUTRITIONAL AND ANTINUTRITIONAL FACTORS OF MOONGBEAN CULTIVARS

Ordinary cooking of presoaked and unsoaked seeds of six cultivars of moongbean (Vigna radiata L.) lowered phytic acid, polyphenols, trypsin inhibitors and improved in vitro digestibility of protein and starch, and availability of Ca, Fe and Zn when compared to unprocessed seeds. However, the effect was more pronounced on ordinary cooking of presoaked seeds followed by cooking of unsoaked seeds and presoaked seeds alone. A significant increase in vitro digestibility of protein (34–48%), and starch (31–62%) may be ascribed to the reduced content of phytic acid (45–65%) polyphenols (34–70%) and trypsin inhibitor activity (42–55%) after ordinary cooking of presoaked seeds of moongbean cultivars. Therefore, ordinary cooking of soaked seeds was the most effective treatment in improving the nutritional quality of moongbean.     

Effects of different cooking methods on chemical compositions,in vitro starch digestibility and antioxidant activity of taro (Colocasia esculenta) corms

The impacts of different cooking methods (boiling, steaming, baking, microwaving and frying) on chemical compositions, starch digestibility and antioxidant activity of taro corms were investigated. Compared with raw taro, boiling and frying reduced crude protein and ash contents. Frying significantly increased crude fat and fibre contents but decreased carbohydrate content. All cooking methods reduced oxalate content, especially frying. Among the cooked products, the boiled taro had the highest rapidly digestible starch (RDS) but the lowest resistant starch (RS) contents. In contrast, the fried taro provided the lowest RDS but the highest RS contents. All cooking methods reduced the total phenolic content and antioxidant activity of taro. The boiled taro had the lowest antioxidant activity but the fired taro provided the highest. Frying was able to retain most of the health-promoting compounds with the lowest oxalate content; however, the high consumption of high-fat fried taro may adversely affect human health.