Optimal soaking conditions and addition of exogenous substances improve accumulation of γ-aminobutyric acid (GABA) in germinated mung bean (Vigna radiata)

Germinated mung beans have been widely used as fresh vegetable or processed healthy food due to their high amounts of bioactive and nutritional compounds, including γ-aminobutyric acid (GABA). The objectives of this study were to investigate the effects of different soaking conditions (temperature, ratios of seeds to water, soaking time, pH, addition of L-glutamic acid (L-Glu) or gibberellic acid (GA3)) and germination time on accumulation of GABA in the germinated mung bean seeds. The mung bean seeds, soaked at 40°C for 4 h with ratio of seeds to water of 1:4 (g mL⁻¹) and then germinated for 7 h, accumulated higher amount of GABA than other soaking conditions and germination time. The addition of GA3 (0.30 mg L⁻¹) or L-glu (1,000 mg L⁻¹) or acidifying to pH 5.5 of the soaking water had high impact on the GABA accumulation. Among them, the soaking water with pH 5.5 was more effective than adding with the L-Glu or GA3 in the production of GABA (1677 mg/kg powder) and essential amino acids (16.56 g/100g powder) in the germinated mung bean seeds. The findings of this study provide useful information to produce GABA-enriched and healthy foods from mung beans.     

The inhibitory effect of albumin extracts from white beans (Phaseolus vulgaris L.) on in vitro iron and zinc dialysability: role of phytic acid

The role of phytic acid in determining iron and zinc dialysability in albumin extracts from raw, cooked and cooked/dephytinized white beans, has been investigated. Albumin extract from raw beans was characterized by high iron (19mg/100g), zinc (6.9mg/100g) and phytic acid (11.5μmol g⁻¹) contents and a low mineral dialysablity (Fe 0.48%, Zn 2.5%). Cooking did not influence the mineral dialysability from beans but significantly increased the dialysability of iron (1%, p < 0.001) and zinc (5.3%, p < 0.001) from the albumin extract. Slight modifications in the composition of inositol phosphates after cooking, both in beans and in albumin extract, were observed. The improvement in iron and zinc dialysability from cooked/dephytinized samples was strictly dependent on the residual IP(6 + 5) (inositol hexa + pentaphosphates) content. Compared to cooked beans, in cooked/dephytinized bean a reduction of IP(6 + 5) of 49% led to an increase of the iron and zinc dialysability (29% p < 0.05 and 42%, p < 0.001, respectively). Albumin extract from this sample showed a reduction of 58% in iron and of 45% in zinc content, an almost complete reduction in IP(6 + 5) content (0.6 μmol g⁻¹) and a strong increase in the iron and zinc dialysability. The albumin digests showed peptides of similar MW profiles but of different amino acid compositions. In particular, in peptides which derived from digestion of albumin extracted from cooked/dephytinized beans, a strong increase in cysteine content was found, indicating that, after the disruption of phytate-mineral-protein complexes cysteine-rich fragments were released. The study indicates that phytic acid is responsible for the low iron and zinc dialysability from the albumin bean fraction and indicates the significance of the amino acid composition of the protein digestion products for the enhancement of mineral dialysability.     

Effects of dehulling,soaking and germination on chemical composition,mineral elements and protein patterns of faba beans (Vicia faba L.)

The effects of dehulling, soaking and germination on the changes in general chemical composition, nine mineral elements and the protein patterns of whole faba beans were studied. Such pretreatments had a significant effect on the changes in the chemical composition of whole beans. Dehulling of beans significantly increased the contents of copper, zinc and potassium, while it significantly decreased the amounts of iron, manganese, phosphorus, calcium, magnesium and sodium compared with whole beans. Whole beans soaked for 12 h, followed by dehulling, had higher amounts of iron, copper, zinc, calcium and sodium, and quite a lower level of potassium, than unsoaked dehulled beans. All of the mineral elements except zinc were significantly increased on germination. No obvious changes in the electrophoretic pattern of faba bean proteins were observed as the seeds were soaked for up to 12 h. Extending soaking time for a further 4 h led to the disappearance of one band at the region of MW 67 KD. Germination of seeds for 3 days initiated disappearance of some bands while other new bands were observed.     

Effects of soaking whole cereal and legume seeds on iron,zinc and phytate contents

The effects of soaking whole cereal (maize, millet, rice, sorghum) and legume seeds (mung bean, cowpea, soybean) on iron (Fe), zinc (Zn) and phytate (Phy) contents were investigated. In all the above cereals, except millet, the molar ratios of Phy/Fe were above than 14, and ratios of Phy/Zn were above 20 while, in legumes, ratios were lower. Soaking whole seeds for 24 h led to leaching of iron and, to a lesser extent, of zinc ions into the soaking medium. Soaking led to a significant (P⩽0.05) reduction in the phytate content of millet, maize, rice and soybean, but did not improve the Phy/Fe molar ratio, while decreasing the Phy/Zn molar ratio only slightly. Soaking on its own was not found to be a good method for improving mineral bioavailability but the results showed that, in combination with other treatments, or with optimized soaking conditions, it could nevertheless prove useful.     

富含益生菌杂豆粉工艺条件优化及货架期预测

以绿豆为原料制备富含益生菌绿豆粉,对其制备工艺条件进行优化,并验证了该制备工艺条件对不同杂豆的适用性,探索了不同杂豆粉的货架期。采用Plackett-Burman设计从8个影响绿豆粉发酵的因素中筛选出浸泡温度、均质压力、进口温度3个显著因素。采用Box-Behnken设计确定最佳工艺参数为浸泡温度50 ℃,均质压力200 Bar和进口温度115 ℃。该条件下绿豆粉中发酵乳杆菌活力的试验值为2.39×108 CFU/g,与理论值2.46×108 CFU/g相比,两者相差不显著。另外,通过考察该条件对红豆、鹰嘴豆、豇豆、豌豆和虎皮芸豆的影响,发现杂豆粉中的益生菌活性可以超过107 CFU/g,达到益生菌食品要求。其中,虎皮芸豆粉含量最高,达到3.27×108 CFU/g,表明绿豆的优化条件对这些杂豆具有普遍适用性。Arrhenius模型预测该系列杂豆粉产品贮藏1年的温度应低于10 ℃。杂豆粉中水分含量较低,有利于贮藏。     

复配粉理化性质与米线质构性质关系的研究

将粳米粉与绿豆淀粉按照一定比例进行混合,得到粳米粉和绿豆淀粉的复配粉体系,并测定了复配粉体系的溶胀性质、糊化性质、凝胶质构性质和拉伸性质,研究了复配米粉体系的拉伸性质与米线质构性质的关系。结果表明:随着绿豆淀粉添加量比例的增加,复配米粉体系的总直链淀粉含量、可溶性直链淀粉含量和不溶性直链淀粉含量明显增加,峰值黏度、谷值黏度、末值黏度、硬度也显著性增加,咀嚼性、拉伸强度和表观弹性模量显著增加,85℃下的溶解度和膨润力显著上升;糊化温度显著降低;衰减值和回生值分别比粳米粉高了33.73 RVU和50.60 RVU;与单一体系相比,由复配粉体系制成的米线呈现较好的硬度、弹性、韧性、蒸煮性和物理性质。当绿豆淀粉∶粳米粉为1∶1时,其制得的米粉的质构性质最好。     

Effect of Soaking and Germination on Polyphenol Content and Polyphenol Oxidase Activity of Mung Bean (Phaseolus Aureus L.) Cultivars Differing in Seed Color

Five mung bean cultivars varying in seed coat color were analyzed for polyphenol content. The effect of soaking and germination on the polyphenol content and polyphenol oxidase activity was investigated. The level of total polyphenols was found to be in the range of 310–340 mg/100 g in whole seeds. Soaking reduced the total polyphenols, whereas germination for 48 h increased total polyphenol content by 41–76%. The hydrolysable tannins, condensed tannins, and hydrolysable tannins/condensed tannins index increased with an increase in period of germination. The total and percent condensed tannins content slightly decreased while hydrolysable tannins increased during germination. Maximum polyphenol oxidase activity of 102–108 units was observed in 24 h germinated seeds. There was no significant correlation found between the polyphenolic content and polyphenol oxidase activity in germinating mung bean seeds. These findings demonstrated that the mung beans are fair sources of polyphenols, thus having great potential as a source of natural antioxidants.     

蛋清蛋白添加对籼米-绿豆粉粉质特性及挤压米粉丝品质特性的影响

将籼米粉、绿豆粉和蛋清蛋白粉按照一定的比例复配,开发高纤维含量的杂粮米粉丝。研究了绿豆和蛋清蛋白的添加对米粉糊化特性、流变特性以及挤压米粉丝微观结构、蒸煮特性和质构等品质特性的影响。结果显示:添加一定量的绿豆粉和蛋清蛋白粉后,混合粉的峰值黏度、最低黏度、最终黏度、回生值、弹性模量、黏性模量均逐渐下降。随着绿豆粉的添加(25%,50%),米粉的蒸煮时间、断条率、蒸煮损失和吸水率均上升,硬度降低,表明米粉的品质显著降低,由扫描电镜图可以发现,加了绿豆粉之后米粉截面变得越来越粗糙,裂纹和孔洞明显增多。但当加入7.5%的蛋清蛋白后,米粉的蒸煮时间、蒸煮损失和断条率均下降,质构特性有一定程度的改善,表明蛋清蛋白良好的凝胶特性有助于提升高纤维含量挤压米粉丝的品质。     

Hypolipidemic and hypoglycemic potential of raw,boiled, and sprouted mung beans (Vigna radiata L. Wilczek) in rats

This study was carried out to investigate the hypolipidemic and hypoglycemic potential of raw, boiled, and sprouted mung beans in rats. Oven dried mung bean powders; raw, sprouted, and boiled were included at 30% level in the diet of seven weeks old male Wistar rats maintained for 5 weeks on high (0.5%) cholesterol diet in comparison with control diet. Low serum glucose and triglyceride concentrations (p < .05) in raw and processed mung bean diets fed rats were supported by low serum insulin level in both raw mung bean diet and boiled mung bean diet fed rats. Hypoglycemic effect in sprouted mung bean fed rats was supported by higher α‐amylase inhibitory activity and α‐glucosidase inhibitory activity of sprouted mung beans. Increase in serum non‐HDL cholesterol concentration and decrease in HDL cholesterol concentration caused by high cholesterol diet were modulated (p < .05) by both boiled and sprouted mung bean diets.

Practical applications

Mung bean is a green legume rich in protein, fiber, antioxidants, and phytonutrients. Hypocholesterolemic and hypoglycemic potential of raw mung beans have been shown previously. It is well known that cooking and processing modulate nutritional and biochemical parameters of foods. However, very limited information is available on the effect of processing on functional properties of legumes. Results of this study showed that boiling and sprouting improved the soluble fiber content and hypocholesterolemic potential of mung beans. Thus, the processed mung beans may be more suitable for developing food supplements for patients with hypercholesterolemia.     

Potential for increasing the amounts of bioavailable zinc in dry beans (Phaseolus vulgaris L) through plant breeding

A whole‐body radioassay procedure was used to assess the bioavailability to rats of zinc (Zn) in seeds of 18 genotypes of beans (Phaseolus vulgaris L) that were grown hydroponically. Dry beans that were labelled intrinsically with ⁶⁵Zn were added to test meals fed to rats that were marginally Zn‐deficient. The amount of Zn in the seeds varied between genotypes and ranged from 26.7 to 62.4 µg g^?1 (from 0.41 to 0.95 µmol g^?1) dry weight (DW). Similarly, the amount of iron (Fe) in the beans varied nearly twofold (from 52.3 to 96.3 µg g^?1 DW), and Zn and Fe concentrations were positively correlated. Concentrations of myo‐inositolhexaphosphate (IP6) plus myo‐inositolpentaphosphate (IP5) varied from 18.1 to 27.3 µmol g^?1 DW. Cultivars with white‐coloured seeds contained relatively small amounts of tannins varying from 0.12 to 0.16 mg g^?1 DW (determined as catechin equivalents) compared to those with coloured seed coats (up to 2.58 mg g^?1 DW). All rats readily ate the test meals so that Zn intake varied directly with seed‐Zn concentration. As indicated by ⁶⁵Zn absorption, the bioavailability to rats of Zn in the seeds varied between genotypes and ranged from about 78 to 95% of the total Zn in the seeds. The bioavailability of Zn to marginally Zn‐deficient rats was not affected markedly by either IP5 + IP6 or tannin in the dry beans. These results demonstrate that the concentration of Zn in dry beans can be increased through traditional plant‐breeding techniques and that this may result in significant increases in the amount of bioavailable Zn in the beans. Increasing the amount of Zn in beans may contribute significantly to improving the Zn status of individuals dependent on beans as a staple food. © 2002 Society of Chemical Industry     

Nutrients and antinutritional factors in faba beans as affected by processing

 The influence on the nutrients content (soluble sugars, starch, dietary fibre and calcium) and antinutritional factors (α-galactosides and phytic acid) of faba beans (Vicia faba, L. major) of soaking in different solutions (distilled water, citric acid, and sodium bicarbonate solutions), cooking the presoaked seeds, dry-heating and germination have been studied. Soaking brought about a decrease in starch, sucrose, fructose, α-galactoside, dietary fibre and calcium content. Glucose was detected in soaked faba beans and soaking did not modify the phytic acid content. Cooking the presoaked faba beans produced a slight decrease in starch, and caused a general drop in α-galactosides, dietary fibre, calcium and phytic acid, with the exception of seeds presoaked in sodium bicarbonate in which cooking did not cause any appreciable changes in comparison with the unprocessed faba beans. Germination caused a sharp reduction in α-galactoside and phytic acid content after 6 days, whilst starch and dietary fibre decreased slightly. Calcium, however, enjoyed a slight increment during germination which was related to the decrease in the content of hemicellulose and phytic acid. Dry-heating caused a noticeable reduction in all the nutrients and antinutritional factors investigated. Of all the treatments studied, germination appears to be the best processing method to obtain nutritive faba bean flour, since it caused a minor decrease in starch content (15% loss), the largest α-galactoside and phytic acid removal (94% and 45%, respectively) and provided an appreciable amount of dietary fibre. Received: 21 December 1997 / Revised version: 19 February 1998     

In vitro Extractability of Calcium, Iron, and Zinc in Finger Millet and Kidney Beans During Processing

ABSTRACT: Finger millet ( Eleusine coracana ) and kidney beans ( Phaseolus vulgaris ) were processed by soaking, germination, autoclaving, and fermentation for incorporation into a complementary food for children. Extract-ability of calcium, iron, and zinc were determined by in vitro HCl-Pepsin and Pepsin-Pancreatin methods after each processing step. Germination significantly increased the in vitro extractability of these minerals, while soaking, autoclaving and fermentation showed a smaller or insignificant effect. Iron extractability was low in germinated, autoclaved and fermented millet, as determined by the pepsin-pancreatin method, but increased 6.8 times with addition of vitamin C. Phytic acid was reduced by 85 and 66% in finger millet and kidney beans, respectively, during the overall processing. These results show that various processing methods, especially germination, increase mineral extractability. Addition of vitamin C and mango could be used to enhance mineral extractabilities, thereby helping to alleviate micronutrient deficiencies in populations subsisting on these foods.     

添加萌发绿豆粉对面包品质的影响研究

为提高杂粮加工利用途径,开发杂粮新食品,本研究以明绿豆为萌发绿豆粉原料,考察了萌发绿豆粉的添加量对面包品质的影响。通过单因素实验确定萌发绿豆粉添加量最适范围为5%～10%,采用正交试验对面包制作配方进行优化得出:萌发绿豆粉添加量6%,酵母添加量3%,白砂糖添加量16%,黄油添加量9%,此时面包具有良好的品质与风味。与普通面包粉的粉质特性相比,当萌发绿豆粉添加量为6%时,面团的粉质特性差异不大,其吸水率升高为68.4%,面团形成时间缩短4.8min,粉质质量指数达145;且可溶性膳食纤维含量增加58.62%,不可溶性膳食纤维含量减少24.26%。     

HCl-extractability of minerals from ricebean and fababean: influence of domestic processing methods

HCl extractable mineral soluble in 0.03 N HCl the concentration of HCl found in human stomach is an index of its bioavailability from foods. The amount of HCl-extractable calcium, phosphorus and iron in raw and unprocessed seeds of rice bean and fababean were (70.2, 55.2), (78.0, 71.2) and (33.4, 35.1), respectively. Among all the domestic processing methods, sprouting was the best method followed by dehulling and soaking (12 h) for improving the extractability of Ca, P and Fe whereas did not affect the total mineral contents. The husks of these legumes had significantly lower levels of extractable Ca, P and Fe.     

浸泡及萌动对芝麻及芝麻酱品质的影响

研究一定温度和湿度条件下不同浸泡和萌动处理对芝麻及芝麻酱基本组分质量分数、功能性成分、矿物质含量及脂肪酸组成的影响。结果显示：未经萌动处理的芝麻浸泡2、5 h时,粗脂肪、粗蛋白质量分数降低;不同浸泡时间芝麻中灰分质量分数均有所降低,粗纤维质量分数显著增加（P＜0.05）,总糖质量分数先升高后降低。随萌动时间的延长,萌动处理后芝麻酱中粗脂肪、总糖和粗纤维质量分数与芝麻中变化一致,粗蛋白质量分数呈先减后增趋势,草酸质量分数逐渐降低,酸价呈波动变化,甾醇含量逐渐增加。萌动处理后的芝麻酱中VE含量均高于对照组芝麻酱,在浸泡20 min、萌动14 h时VE含量达到最大值（49.96 mg/100 g）,比对照组增加49.36%;萌动24 h时,萌动处理后的芝麻酱中芝麻酚的含量均明显高于未经萌动处理芝麻酱;萌动处理后芝麻酱中的Ca含量明显增加,K含量下降。通过主成分分析,发现影响萌动处理后芝麻酱品质的主要指标为粗脂肪质量分数、VE含量等。经过浸泡和萌动处理的芝麻酱中花生酸不再存在。结果表明萌动处理是制备低脂肪质量分数、高VE含量芝麻酱的一种新途径。     

Effect of blanching and soaking on winged beans (Psophocarpus tetragonolobus)

The effects of blanching and soaking on the properties of two cultivars of winged bean (Psophocarpus tetragonolobus) seeds and flour were investigated. Blanching increased the rate of water uptake, total water absorbed and the percentage of beans rehydrated during soaking, but, decreased the protein solubility of the flour. Blanching for a short time, 1 min for Rajburi TIS 0172 and 10 min for the Suwan farm 2702 cultivars, inactivated almost all the lipoxygenase activity but had little effect on the trypsin inhibitor activity.     

Influence of natural and controlled fermentations on α-galactosides, antinutrients and protein digestibility of beans (Phaseolus vulgaris L.)

The influence of natural fermentation (NF) and controlled fermentation (CF) in diminishing the content of antinutrients, α‐galactosides and increments in in vitro protein digestibility was investigated. The dry bean (Phaseolus vulgaris) flour was the substrate used in this research study. A decrease in raffinose oligosaccharide, antinutritional components and pH was observed in both types of fermentation. The natural lactic fermentation of ground beans produced significant increase (P < 0.05) in protein digestibility. For all varieties of beans, raffinose concentration reduced significantly to an undetectable level after 96 h of NF. CF did not have any significant effect on the reduction of the α‐galactosides content of the flours during fermentation. NF is an inexpensive method by which consumers can obtain good‐quality protein. Both types of fermentation diminish antinutrients and improve the nutritional value of the bean flour, and indicate the potential to use bean flour as an ingredient for fabricated foods.     

贮藏方式对绿豆球蛋白结构与溶解性的影响

为明确不同贮藏方式对绿豆蛋白质结构和溶解性的影响,以新鲜绿豆和在室温及4 ℃气调贮藏18个月的绿豆为原料,利用傅里叶红外光谱、DTNB比色法、Folin酚法等方法,探究发现室温条件下,绿豆球蛋白α-螺旋结构最大增加4.73%,巯基含量最大降低0.00487、表面疏水性最大降低20.78667,二硫键含量最大升高0.00177;4℃条件下,绿豆球蛋白α-螺旋结构最大增加1.65%,巯基含量最大降低0.00174,表面疏水性最大降低5.48667,二硫键含量最大升高0.00048。经过贮藏后,绿豆球蛋白的溶解性降低,不同贮藏方式变化不同。室温贮藏后的绿豆球蛋白结构和溶解性与新鲜绿豆球蛋白差异显著（P>0.05）;而4 ℃气调贮藏后的绿豆球蛋白结构和溶解性与新鲜绿豆差异不显著（P<0.05）。说明4 ℃和气调贮藏可以减少绿豆球蛋白结构的变化与溶解性的变化,从而更好地保持其品质。     

中老年人马铃薯复合米粉的研制及消化性研究

通过不同比例配比优选出最佳的马铃薯与大米的比例,添加不同量的大豆、绿豆、小米,测定其黏度值,并结合感官评分筛选出各单因素的添加量,再采用混料设计确定马铃薯复合米粉的最佳配方,结合中老年人生理特征对制备的马铃薯复配米粉进行体外模拟消化试验。结果表明:马铃薯复配米粉的最佳配方为黄豆12.31%,绿豆20.84%,小米24.36%,马铃薯14.88%,大米27.61%,淀粉消化率为82.48%,符合中老年人对营养的基本需求。     

超声和碳酸氢钠处理对绿豆浸泡特性的影响

为了改善绿豆的质地特性,提高其浸泡效率,本文研究了超声和碳酸氢钠作用下绿豆的吸水动力学、水分分布、水分迁移、硬度、种皮结构以及总酚和植酸含量的变化。超声对绿豆吸水特性、硬度和营养成分含量的影响与绿豆表皮结构变化有关。400 W超声使绿豆表皮形成微孔通道,提高绿豆的吸水速率以及自由水和结合水的含量,降低硬度,总酚和植酸含量也显著降低（P<0.05）。1.5%碳酸氢钠对绿豆浸泡特性的影响可能是通过改变浸泡液的酸碱性发挥作用。碳酸氢钠会提高浸泡液pH,从而减缓吸水速率,降低总酚含量,抑制植酸含量降低,但对绿豆硬度的降低作用不明显,并且碳酸氢钠组的自由水和结合水含量与对照组有一定差异。若以最低硬度为评价指标,则对照组和1.5%碳酸氢钠组的最佳浸泡时间为7 h,而400 W超声组最佳浸泡时间为4 h。本文探明了超声和碳酸氢钠处理对绿豆浸泡特性的影响机制,可为超声波技术以及碳酸氢钠预处理技术在杂粮食品开发中的应用提供理论指导。