Characterization of Red Bean (Phaseolus radiatus var. Aurea) Starch and Its Noodle Quality

Red bean (Phaseolus radiatus var. aurea) starch was isolated by a wet-milling process and steeping in 0.1% sodium hydroxide which gave the best starch purity. Physical properties of the starch including granule sizes, gelatinization temperature range, iodine affinity, X-ray diffractogram, swelling and solubility pattern, Brabender amylogram, gel strength and degree of syneresis, were examined. Starch noodles were prepared from red bean starch and compared with those from mung bean. Noodle quality was exmained by solid loss during cooking, tensile strength and organoleptic tests. The results indicated that red bean starch noodles gave fairly good quality, although not as good as mung bean starch noodles.     

Characteristics and Concentrations of α-Amylase Inhibitor in Phaseolus vulgaris Biotypes

Flours from six legume species (lentil, lima bean, field pea, chickpea, fababean, mung bean) were devoid of α-amylase inhibitory activity but five biotypes of Phaseolus vulgaris showed activities of 27 to 40 units/mg protein. Air classification of the pin milled flours yielded fine fractions which contained 37% (black bean) to 61% (navy bean) protein and 38 to 66 units of inhibitor activity/mg protein, respectively. The coarse starch fractions were proportionately depleted in protein content and inhibitor activity. The partially purified amylase inhibitor from navy bean was active towards porcine pancreatic α amylase. The optimum pH for inhibition was 5.6 - 5.7, with the inhibitor being most stable at pH 6.9 after 4 h incubation at 37°C. The inhibition was faster at 37°C than at 25°C. Although retaining most of its inhibitory power between 37°C–60°C, the navy bean inhibitor showed a complete loss of activity after 20min at 90°C.     

Structural and some nutritional characteristics of Velvet bean (Mucuna pruriens) and Lima bean (Phaseolus lunatus) starches

Velvet bean (Mucuna pruriens) and lima bean (Phaseolus lunatus) starches were isolated from seeds and their structural characteristics evaluated using XRD, size‐exclusion chromatography and light scattering analyzes. Total starch, available starch, RS and in vitro digestibility were also determined. Structural and nutritional characteristics of Velvet bean and Lima bean starches were compared to those of commercial corn starch. The legumes starches presented a C‐type XRD pattern and crystallite sizes of 43.1 Å for velvet bean and 48.3 Å for lima bean. Lima bean starch average molar mass (4.9 × 10⁶ g/mol) was slightly higher than the velvet bean starch (3.04 × 10⁶ g/mol). Size‐exclusion chromatography indicated structural similarity between the lima bean and corn starches which differed from that of the velvet bean starch. Hydrodynamic radius (R_H) for the velvet bean and lima bean starches was 45.5 and 55 nm, respectively, and their radius of gyration (R_G) was 67.7 and 82.5 nm, respectively. Total starch content in all three starches was greater than 98%. Their complex crystalline structure provided the legume starches lower in vitro digestibility values than the corn starch. RS content in both the velvet bean starch (7.72%) and lima bean starch (5.66%) was higher than in the corn starch, essentially qualifying these polysaccharides as natural dietary fiber sources, with the associated physiologic advantages.     

The influence of proteolytic and cytolytic enzymes on starch degradation during mashing

The objective of this research was to investigate the impact of proteolysis and cytolysis on starch degradation over the course of the mashing process. A proteolytic enzyme (Neutrase 0.8L, Novozymes) and a number of cytolytic enzymes (barley β‐glucanase from Megazyme, Shearzyme 500L and Ultraflo Max from Novozymes) were used to test their efficiency on starch degradation during mashing. The proteolytic and cytolytic enzymes had positive effects on the levels of starch‐degrading enzymes and starch solubilization during mashing, resulting in higher levels of wort sugar compared with the control, indicating that proteins and residual non‐starchy polysaccharides limited the digestibility of starch during mashing. Moreover, the proteolytic enzyme showed a significantly greater improvement than the cytolytic enzymes, yielding a 57% increase in β‐amylase, a 173% increase in limit dextrinase, rapid starch solubilization during mashing and a higher percentage of fermentable sugars in resultant wort. The increases in limit dextrinase and β‐amylase promoted by the protease suggest that sufficient proteinaceous inhibitor existed in the wort during mashing to inhibit their activities, leading to the unavailability of β‐amylase and especially limiting dextrinase. Furthermore, Ultraflo Max, which contained a β‐glucanase–xylanase mixture, showed a greater improvement than either the individual β‐glucanase or the xylanase on starch hydrolysis. These findings suggest that β‐glucanase is the major enzyme responsible for the degradation of cell walls, and that the complete hydrolysis of the residual cell walls depends on the synergistic effect of β‐glucanase and xylanase. The results suggest that brewers should adjust the degradation of the cell walls and correct the degree of protein modification in order to obtain the desired wort composition. Copyright © 2014 The Institute of Brewing & Distilling     

产纤维素酶海洋菌株的筛选及鉴定

从汕尾一鲍鱼场采集的样品中分离到120株菌，经过刚果红染色，初筛得到产纤维素酶酶活较高的8株菌。对这8株菌进行了纤维素酶和滤纸分解的研究。结果表明，这8株菌所分泌的纤维素酶主要为胞外酶，其中7株能降解滤纸条。在这8株菌中，JK29与GZ-18-2在分泌纤维素酶活力及降解滤纸能力方面均很强，其分解纤维素的酶活分别达到10．3U／ml和11．5U／ml，而分解滤纸的酶活力则分别为6．0U／ml和5．67U／ml。经过鉴定，这两株菌分别为Vibrio alginolyticus与Aeromonas sobria，可用于海洋菌株产纤维素酶的进一步研究。     

Inhibitory Effects of Phenolics and Saponins From Commonly Consumed Food Legumes in China Against Digestive Enzymes Pancreatic Lipase and α-Glycosidase

Total phenolic and saponin components were extracted from 13 commonly consumed food legumes produced in China, and then a systematic comparative study was conducted to investigate their inhibitory effects against digestive enzymes, pancreatic lipase, and α-glycosidase, respectively. Saponin extract (1 mg/mL) from black bean exhibited the highest (41.8%) pancreatic lipase inhibitory effect, followed by phenolic extract from adzuki bean with 36.3%, saponin extract from yellow soybean with 34.1%, saponin extract from pinto bean with 32.6%. It is worth mentioning that both phenolic and saponin extracts from the mung bean, adzuki bean, lima bean, and pinto bean exhibited inhibitory effects against pancreatic lipase. Among four beans, the adzuki bean had the highest inhibitory effects against pancreatic lipase activity. In the α-glycosidase assays, phenolic extracts exhibited stronger α-glycosidase inhibitory activity than that of saponins in general. Phenolic extracts of the adzuki bean, black bean, fava bean, lentil, rock bean, and red kidney bean inhibited over 80% of α-glycosidase activity at the concentration of 1 mg/mL. Both phenolic and saponin extracts from the adzuki bean and rock bean exhibited inhibitory effects against α-glycosidase. The results indicate that adzuki bean is one of the best target beans for further study on their anti-obesity and anti-diabetes effects via cell and animal models.     

HPLC Determination of Sugars and Starch in Green Beans

A reversed-phase HPLC method using a Spherisorb NH₂ column and 85:15 v/v acetonitrile/water as mobile phase was developed for determination of starch and soluble sugars (glucose, fructose and sucrose) in plants. When applied to pure starch samples, the analytical method was as accurate as the official AOAC method and had better precision (coefficient of variation 0.87% vs 1.27%). When applied to green bean (Phaseolus vulgaris L.), recovery was 97.7% for starch, 98.0% for glucose and 98.1% for both fructose and sucrose.     

Microencapsulation of β‐carotene using native pinhão starch,modified pinhão starch and gelatin by freeze‐drying

Beta‐carotene was microencapsulated by freeze‐drying using native pinhão starch, hydrolysed pinhão starch 6 dextrose equivalent (DE), hydrolysed pinhão starch 12 DE and the mixture of these materials with gelatin as coating material. The purpose of this research was to produce and characterize these microcapsules. The capsules’ efficiency, surface content, moisture, morphology, solubility, particle size and glass transition temperature were analysed. The hydrolysed pinhão starch 12 DE showed the highest total β‐carotene content and the lowest surface β‐carotene content, unlike the native starch. Using scanning electron microscopy, it was observed that all microcapsules presented undefined shapes. The samples with gelatin had wider particle size distribution, higher diameters, lower solubility and higher glass transition temperature when compared with other the samples. Results obtained suggest that the modified pinhão starch can be considered as potential wall material for encapsulation of β‐carotene.     

Investigations of the Great Northern Bean (Phaseolus vulgaris L.) Starch: Solubility, Swelling, Interaction with Free Fatty Acids, and Alkaline Water Retention Capacity of Blends with Wheat Flours

The solubility and swelling of Great Northern bean (Phaseolus vulgaris L.) starch was both temperature and pH dependent. Acetylation of starch decreased the solubility while oxidation increased the solubility as a function of temperature. Solubility of purified starch was highest at pH 6.0. Over a temperature range 60–90°C, acetylation increased swelling while oxidation reduced it. Both acetylation and oxidation resulted in reduced swelling of starch over a pH range 2–10. Addition of fatty acids (palmitic, stearic, and linoleic) to the purified starch reduced the Brabender Amylograph viscosity and raised the gelatinization temperature of starch. Replacement of wheat flours by starch increased the alkaline water retention capacity to a similar extent for the two flours tested.     

Physicochemical characterization of mung bean starch

Starch from mung bean (Vigna radiata) was isolated and some of the important characteristics determined. The yield of starch was 31.1% on a whole-seed basis. The shape of the starch granule was oval to round to bean shaped, with granules 7–26 μm in diameter. Scanning electron micrographs revealed the presence of smooth surfaces. The gelatinization temperature range was 58–67–82°C and the enthalpy of gelatinization was 18.5 J/g. The total amylose content was 45.3%, of which 12.1% was complexed by native lipids. The X-ray diffraction pattern was of the ‘C’ type and the X-ray intensities were much stronger than in other legume starches. The starch exhibited a high swelling factor ( 43.6 at 95°C) in water. The viscoamylographic examination of the starch paste (6% w/v) showed the absence of a peak viscosity, a low 95°C viscosity [200 Brabender units (BU)], an increase in consistency ( 140 BU) during the holding cycle at 95°C and a set-back of 220 BU. Native granules were readily hydrolyzed by porcine pancreatic α-amylase (76.4% in 72 h). Retrogradation of mung bean starch (as measured by changes in syneresis, gel strength, enthalpy and X-ray diffraction intensities) appeared to be more severe than in other legume starches.     

CHARACTERISTICS OF STARCH FROM WATER CHESTNUT (TRAPA BISPINOSA ROXB.)

The physicochemical properties of the starch extracted from krajub (Trapa bispinosa Roxb.) were investigated. Scanning electron microscopy of the starch granules showed that they were either oval or round in shape with small horn(s) protruding from the surface. Amylose content of the krajub starch was 29.62% (dry weight basis [dwb]). The pasting temperatures of 6–8% starch suspension were 81–83C. Brabender amylogram showed no peak viscosity and very low breakdown, indicating high heat and shear stability of the starch suspension. The starch pastes highly retrograded and formed an opaque gel. The X‐ray diffraction patterns of the starch revealed a C‐type crystallite. The starch granules were more resistant to acid hydrolysis (2.2 N HCl at ambient temperature) than mung bean starch (C‐type crystallite).     

PROCESSING AND FUNCTIONAL PROPERTIES OF YAM BEANS (SPHENOSTYLIS STENOCARPA)

The proximate and selected functional properties of five flours from yam bean (YB) made after the grains were not processed (raw) and processed as boiled, fermented, roasted and malted, were determined. The functional properties were water and fat absorption, gelation, emulsification and whippability. An improvement was observed for protein content of flours processed beans compared to raw flour. Fermentation improved the oil content of the flour. The emulsifying and foaming capacities (50.7 and 40.20%, respectively) observed for raw flour were significantly higher than those for the flours from processed bean. Gelation was significantly (P < 0.05) increased and decreased by fermentation and malting of the bean, respectively. The water absorption capacities ranged from 131.9% in raw flour to 218.8% in flour boiled beans. There were no significant (P > 0.05) differences in the fat absorption capacities of all flours except for the one of fermented beans (0.40 mL/g), which was significantly lower than the value (0.73 mL/g) obtained for the flour from boiled beans. Although a high foaming capacity was observed for raw flour, it was less stable when compared with that of the processed bean flours. Overall, YB flour was found to exhibit good functional properties, and has a great potential for use as an ingredient in selected food systems.     

AB-8大孔树脂对红腰豆总黄酮纯化工艺的优化及其体外抗氧化活性研究

以红腰豆总黄酮粗提液为原料,研究大孔树脂对红腰豆黄酮的纯化工艺和效果,比较了8种树脂对红腰豆总黄酮的静态吸附和解吸性能,对AB-8型大孔树脂分离纯化红腰豆总黄酮进行了单因素、Box-Benhnken中心组合设计和响应面法优化试验,并考察了红腰豆总黄酮纯化前后体外抗氧效果。结果表明,AB-8树脂为纯化红腰豆总黄酮的最佳树脂,确定了其最佳的吸附工艺条件为：上样质量浓度4.0 mg/mL,上样液pH 6.3,上样流速2.0 mL/min,上样体积5.0 BV,在此条件下吸附率可达(98.03±0.30)%;最佳的解吸工艺条件为乙醇体积分数75%,洗脱流速3.0 mL/min,洗脱体积2.0 BV,在此条件下解吸率可达(94.52±0.24)%。纯化后红腰豆总黄酮纯度提高了约2.85倍,纯化前DPPH.、.OH和O_2-.的清除率IC₅₀值分别为1.18、1.40、6.51 mg/mL,纯化后分别为0.37、0.82、1.77 mg/mL,纯化后红腰豆总黄酮提取物的体外抗氧化活性明显增强。     

Physicochemical and Functional Properties of Dry and Wet Milling Products of Red Cowpeas

Physicochemical and functional properties of dry- and wet-milled red cowpea flour, protein and starch were evaluated. Bulk density of drymilled red cowpea protein was lower than that of wet-milled protein isolate. Dry-milled starch was darker than wet-milled starch. Gelatinization temperature of starch (64–68–74°C) was quite similar to that of mung bean starch. At water to red cowpea starch ratios of 3:1 and 2:1, DSC thermograms showed a single endotherm with T_o of 68.5–69.0°C, T_p of 73.0–73.5°C, T_m of 79.5–80.0°C, and –ΔH of 4.0–4.6 cal/g starch. Pasting properties of red cowpea starch showed a type C amylogram, similar to mung bean starch. By mixing various quantities of red cowpea starch to tapioca starch pasting properties of the latter could be varied. Water and oil absorptions of cowpea flours increased with the increase in protein contents, as did their emulsifying activity and foaming properties. Emulsion and foam stabilities were quite similar among all the red cowpea products, except for protein isolate which were considerably lower, likely due to a greater degree of protein denaturation during precipitation and drying of the isolate. Composite flours made from mixing wheat and red cowpea flours exhibited dough mixing properties indicative of their potential use in baked products.     

Structure and Viscoelastic Properties of Starches Separated from Different Legumes

A comparison between the morphological, structural, thermal and viscoelastic properties of starches separated from pigeon pea, chickpea, field pea, kidney bean and blackgram was made. The shape of the starch granules in the different legumes varied from oval to elliptical or spherical. X-ray diffraction of the legume starches indicated a typical C-pattern (mixture of A- and B-type). Granules of blackgram and pigeon pea starch had a higher degree of crystallinity than those of field pea and kidney bean starches. Apparent amylose content of field pea, kidney bean, chickpea, blackgram and pigeon pea starch was 37.9%, 36.0%, 34.4-35.5%, 32.9-35.6% and 31.8%, respectively. Distribution of isoamylase-branched materials among the starches revealed that the proportions of long and short side chains of amylopectin ranged between 13.6-18.5% and 41.7-46.5%, respectively. Field pea and kidney bean starch had the highest apparent amylose content and the lowest amount of long side chains of amylopectin, respectively. Blackgram and pigeon pea starch possessed higher proportions of both long and short side chains of amylopectin than field pea and chickpea starches. The onset, peak and conclusion temperatures of gelatinization (T_o T_p and T_c, respectively) were determined by differential scanning calorimetry. T_o and T_c ranged from 59.3 to 77.3°C, 66.8 to 79.6°C, 55.4 to 67.6°C and 68.3 to 69.3°C, respectively, for chickpea, blackgram, field pea and kidney bean starch. The enthalpy of gelatinization (ΔH_gel) of field pea, kidney bean, chickpea, blackgram and pigeon pea starches was 3.6, 3.0, 2.6-4.2, 1.6-1.7 and 2.6 J/g, respectively. Pastes of blackgram and pigeon pea starches showed lower storage and loss shear moduli G′ than field pea, kidney bean and chickpea starches. The changes in moduli during 10 h at 10°C revealed retrogradation in the order of: field pea> kidney bean> chickpea> blackgram> pigeon pea starch. In blackgram and pigeon pea starches, the lower proportion of amylose plus intermediate fraction and higher proportion of short and long side chains of amylopectin are considered responsible for the higher crystallinity, gelatinization temperature and enthalpy of gelatinization.     

Effect of the Addition of Common Bean (Phaseolus vulgaris L.) Flour on the In Vitro Digestibility of Starch and Undigestible Carbohydrates in Spaghetti

Abstract: Spaghetti is considered to be a slowly digestible starch food, a feature ruled by the particular physical properties of the product. Several studies have been reported to increase nutritional value of spaghetti, using legumes. We have studied the addition of common bean flour on the starch in vitro digestibility. Spaghetti was prepared with semolina and different concentrations of common bean flour (0%, 15%, 30%, and 45%, w/w). Proximate analysis, optimal cooking time, and cooking loss were estimated in crude spaghetti. Total, available, and resistant starches, indigestible fractions, and in vitro starch hydrolysis kinetics were accomplished in cooked spaghetti. Pasta with 30% and 45% of common bean flour showed higher values of protein. Particularly, the lowest cooking time was observed for composite spaghetti with 45% of common bean flour. There was a significant increase in cooking loss when common bean flour in the composite was added. Composite spaghetti samples with increasing common bean flour showed decreasing values of total starch but an important increase in the resistant starch (RS) level and indigestible insoluble fraction values. Plain pasta made with semolina showed the highest enzymatic hydrolysis rate, which decreased when common bean flour was added to the spaghetti. Spaghetti with a higher level of common bean flour was more slowly available, which may have positive implications for human health.     

十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法测定饮料中红豆含量

目的建立十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)法定量分析植物蛋白饮料中红豆成分含量的方法。方法从8个主要蛋白条带中选取一个蛋白条带作为定量标记蛋白,配制红豆标准品进行SDS-PAGE实验,用Image J软件测量特征蛋白条带的灰度面积值,得到特征蛋白条带灰度面积与红豆含量关系的标准曲线。最后以市售红豆饮料为实际样品,检验该方法对于复杂样品的实用性。结果红豆含量在3~8 g/100 mL范围内,特征蛋白条带灰度面积与红豆含量呈良好的线性关系(r~2=0.9944)。向市售样品中添加2 g/100 mL标品,得到加标回收率为99.2%,相对标准偏差为1.68%(n=3)。结论该方法为红豆饮料中红豆含量的检测提供了一个可行的手段。日后,该方法可推广应用于其他以蛋白为标志物的饮料成分的定量测定。     

杂粮复合豆沙营养及功能品质评价

以薏米、苦荞分别与红小豆、红芸豆制成杂粮复合豆沙,检测其蛋白质、氨基酸、淀粉等宏量营养素以及黄酮、多酚、花青素等微量活性成分含量,并对营养品质及功能成分进行综合评价。结果表明,与红小豆沙和红芸豆沙相比,薏米或苦荞复合豆沙的蛋白质、总淀粉、慢消化淀粉、抗性淀粉、氨基酸总量、必需氨基酸、黄酮、多酚、花青素等营养功能成分含量均显著增加(P0.05)。基于主要营养、功能物质含量,采用主成分分析(PCA),7个豆沙样品营养价值由高到低依次为:苦荞红小豆沙薏米红小豆沙苦荞红芸豆沙薏米红芸豆沙红小豆沙红小豆沙(市售)红芸豆沙,这表明杂粮复合豆沙具有更高的营养功能品质。     

PROCESSING OF LEGUMES: RESISTANT STARCH AND DIETARY FIBER CONTENTS

Resistant starch (RS) and dietary fiber contents of differently processed Bengal gram (chickpea), black gram, green gram and red gram (pigeon pea) dhals were determined. In traditionally cooked dhals, RS increased 1.6 to 9 fold, whereas pressure cooked dhals showed a 2.1 to 8 fold increase over that of uncooked dhals. Deep fat frying of a black gram food product resulted in a 3 fold increase in RS. Germination of the whole legumes resulted in only a small increase in RS; but the content of insoluble dietary fiber was higher. Pressure‐cooking of red gram dhal in the presence of additives showed considerable variation in the yield recovery of RS. Lactic acid and ascorbic acid, added after cooking, enhanced (>100%) RS; addition of hydrocolloids had only marginal effects; whereas addition of spice powder before cooking lowered RS, an effect similar to the one observed upon addition of oils/lipids.