大豆发芽过程中抗原蛋白降解及营养特性变化

研究大豆发芽过程中抗原蛋白降解、抗原活性和营养成分的变化规律。结果表明,发芽期间,大豆子叶组织结构变得疏松;主要抗原蛋白β-伴球蛋白的α′-和α-亚基降解较快,而β-亚基降解缓慢。大豆11S球蛋白的酸性链降解快,而碱性肽链降解慢。ELISA分析表明,在发芽的前4 d中,β-伴球蛋白和11S球蛋白的抗原活性剩余率分别为58%和76%,延长发芽时间抗原活性降低较小。整个发芽期间,必需氨基酸和总氨基酸含量变化不大,但天冬氨酸含量显著增加,谷氨酸的含量明显降低。抗坏血酸含量在发芽第3 d时达到最大值,延长发芽时间,其含量降低。综上可知,在发芽4 d时大豆的食用安全性和营养价值较为理想。     

大豆发芽过程中营养成分变化规律的研究

通过对大豆发芽过程中营养成分含量变化进行分析,结果表明脂肪和总糖含量随时间的延长而下降,而蛋白质、还原糖、VC和异黄酮含量在发芽后均较未发芽时增加。其中VC的含量增加最多,到第7天时候,每100 g的大豆芽中含有9.7 mg的VC。大豆在发芽1 d时,蛋白质的含量有所下降,随后缓慢增加,第7天的蛋白质含量比未发芽前增加了11%。还原糖含量在其发芽的过程中平稳地上升,在第7天的时候达到9.38 g/100 g,比未发芽前增加了2.32倍。异黄酮含量在发芽4 d时达到最大值0.51 g/100 g,以后平缓。     

大豆发芽过程中营养成分变化

研究大豆在30℃发芽0d、1d、2d、3d时游离氨基酸含量、游离脂肪酸含量、维生素C含量变化。随着发芽时间延长,游离氨基酸含量增加,发芽3d时含量为2.895g/L,比未发芽大豆中游离氨基酸含量增长10.6%;游离脂肪酸含量在发芽第1天稍下降,随发芽时间增长又增加,到发芽第3天时含量达1.4888%,但仍比未发芽大豆含量稍低:维生素C含量在发芽过程中增加最多,到发芽第3天时含量已达0.131g/L,是未发芽大豆11.42倍。     

乳酸钙处理对发芽大豆植酸降解和主要营养物质含量的影响

研究低浓度乳酸钙对大豆发芽过程中植酸降解以及主要营养物质含量的影响。在大豆发芽4?d期间,施用0.27?mmol/L乳酸钙喷淋对大豆植酸降解效果显著,并且提高锌、铁元素的生物利用率,利于人体对其吸收。此外,可溶性蛋白、可溶性糖含量不断下降,而游离氨基酸的含量随着可溶性蛋白含量下降而上升。总蛋白质含量与氨基酸总量基本保持稳定或略有下降,但氨基酸组成发生较大变化,在17?种氨基酸中,天冬氨酸和组氨酸含量随着发芽时间的延长而增加,其他氨基酸含量均呈下降趋势。乳酸钙处理条件下,促进了天冬氨酸和缬氨酸等氨基酸的累积和其他氨基酸含量的降低。乳酸钙作为优质钙元素补充剂,用低浓度喷淋处理可促进大豆发芽并大量降解抗营养因子植酸,提高营养品质。     

大豆发芽过程中成分变化及营养特性的研究

探究大豆发芽过程中各营养成分的变化。对大豆中各营养成分发芽前后含量进行测定。结果,蛋白质的含量先下降1.64 g/100 g,后又上升至40.80 g/100 g;脂肪的含量先增长了0.52 g/100 g,后又平缓下降;还原糖含量一直平稳上升;VC含量剧增,为未发芽前的13.09倍;氨基酸总量增加;植酸降解率达33.87%;异黄酮含量在72 h时增长到最大值,为0.39 g/100 g;大豆发芽完全时γ-氨基丁酸(GABA)富含量最多。大豆经过发芽后可利用价值更高。     

大豆发芽过程中维生素C、异黄酮含量变化及其抗氧化性的研究

目的研究大豆发芽期间维生素C、异黄酮及抗氧化活性的变化。方法采用2,6-二氯酚靛酚滴定法和紫外分光光度法测定大豆发芽期间不同芽长的维生素C、异黄酮含量及DPPH和超氧阴离子自由基清除率,确定大豆发芽的最佳长度。结果维生素C的含量随着发芽长度的增加而增加,当发芽长度为5 cm时,每100g大豆芽中含维生素C为120.09 mg;大豆异黄酮在芽长3 cm时达到最高值,含量比未发芽前增加了17.28%,之后呈下降趋势,但下降趋势不大;较超氧阴离子自由基,未发芽大豆提取物对DPPH自由基表现出更强的清除能力;发芽后,在芽长为4 cm时对两种自由基的清除能力最强。结论大豆发芽到4 cm时为最佳食用时间。     

不同品种大豆发芽过程中抗坏血酸合成积累的比较研究

测定了鲁豆2号、淮豆l号、吉林3号和楚秀等4种不同品种大豆发芽过程中抗坏血酸含量的变化情况，结果表明供试大豆在发芽过程中抗坏血酸含量均显著增加，说明大豆发芽过程中开始了抗坏血酸的合成代谢。发芽4天后的鲁豆2号和淮豆l号的抗坏血酸含量高于相同发芽条件下的吉林3号和楚秀，表明不同品种发芽大豆中抗坏血酸的合成能力不同。在4种发芽大豆中均检出半乳糖酸内酯脱氢酶(GLDH)，其活性受光照条件的影响，蓝光、白光、紫外光对GLDH活性具有促进作用，紫外光的促进作用最显著。在相同光强和相同时间的紫外光照射下，楚秀和吉林3号的抗坏血酸增加量高于鲁豆2号和淮豆1号，表明不同大豆品种对紫外光的敏感性不同。     

大豆发芽过程中蛋白质的水解作用研究

研究大豆发芽过程中内源蛋白酶的蛋白水解作用,分析大豆种子吸水量、内源蛋白酶活性、发芽长度、游离氨基酸含量及发芽后大豆蛋白质亚基组成的变化。结果发现,大豆在发芽48h以后,大豆芽表现出快速的增长,其内源蛋白酶的活性达到最高,水解物游离氨基酸的含量变化规律与蛋白酶的活性变化规律一致。大豆发芽过程中,内源蛋白酶主要使11S大豆球蛋白的碱性亚基B3发生降解,对贮藏蛋白的主要成分7S和11S几乎没有作用。     

大豆制品文摘

用氯化钙和藻朊酸钠的混合水溶液提取发芽大豆和未发芽大豆的蛋白质,通过测定蛋白质利用率,发现发芽提高了营养价值。含藻朊酸蛋白的利用率低,这是因为胃蛋白酶的蛋白分解作用受到了抑制。发芽三天的大豆中有30%的胰蛋白酶活性受到抑制。发芽后,每百克干豆维生素C含量从0增加到25毫克。     

3种大豆发芽过程中营养成分变化规律研究

研究青豆、黑豆和黄豆发芽过程中营养成分的变化规律,为发芽大豆食品生产和加工提供试验依据。采用一定的温度与湿度对大豆发芽条件进行控制,定期抽样测定发芽大豆中的粗蛋白、粗脂肪、还原糖、Vc和异黄酮的含量。结果表明:与发芽1d后相比,发芽7d后青豆、黄豆、黑豆中蛋白质含量分别比发芽1d后增加了24.03%,24.28%,22.88%,还原糖含量分别增加了129.06%,127.17%,125.73%,VC的含量分别增加了831.37%,663.97%,807.07%,粗脂肪的含量分别减少了37.28%,35.68.28%,36.69%。3种大豆都在发芽4d后异黄酮的含量达到最大值,其中黑豆中异黄酮的含量最高为0.531%。     

Free and bound form bioactive compound profiles in germinated black soybean (<Emphasis Type="Italic">Glycine max</Emphasis> L.)

This study investigated the transition between the free and bound forms of functional compounds in germinated black soybean. Black soybean was germinated at 25°C over 6 days and then the free and bound forms of functional compounds were extracted. Total free polyphenol, flavonoid, and phenolic acid contents in raw black soybean increased from 1.03 mg GAE/g, 0.29 mg CE/g, and 315.67 μg/g to 1.44mg GAE/g, 0.64mg CE/g, and 511.01 μg/g, respectively, by 4 days after germination. Changes to phenolic acid compositions can be divided into four groups, and the germination process can convert compounds to phenolic acid via anabolism and catabolism. The highest total free isoflavone content in germinated black soybean (3,724.40 μg/g) was observed at 4 days. Bound polyphenol, flavonoid, phenolic acid, and isoflavone contents decreased as the germination period increased. These results suggest that the germination process increased compound functionality in black soybean.     

INFLUENCE OF GERMINATION ON SAPONINS IN SOYBEAN AND RECOVERY OF SOY SAPOGENOL I

Soysaponins are considered major bioactive components. Ethanol extractives prepared from mature soybean and germinated seeds (0–4 days) were examined for saponin content (found to be 2.8 and 6.1–8.9%, respectively). The saponin content increased 3.2 times after germination. The predominant hydrolytic product of saponin – soysapogenol I – content increased from 1.8 to 7.3% during the course of germination. Defatted soy flour, soy protein isolate and toasted flour contain saponins at 2.3–3.5%, suggesting that the germinated soybean seeds are the richest source of saponins among soybean products.     

Macronutrients,Phytochemicals, and Antioxidant Activity of Soybean Sprout Germinated with or without Light Exposure

This study examined the macronutrients, phytochemicals, and antioxidant activities of yellow soybean sprout (YSS) and green soybean sprout (GSS) with different germination days. YSS and GSS were obtained by sprouting soybean in darkness or with light exposure at 21 °C. Lipid, protein, carbohydrate, and ash contents were analyzed before and after soybean germination. Phytochemicals (total phenolic compounds, saponin, and isoflavone) were also determined. DPPH, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) were determined to examine the antioxidant activities of soybean sprout. Results showed YSS had a higher yield than GSS. Based on dry mass composition, 7‐d germination of GSS decreased 14% protein, 37% lipid, 22% carbohydrate, and 16% ash, whereas 7‐d germination of YSS decreased 6% protein and 47% lipid. Carbohydrate did not change and ash significantly increased for the 7‐d germinated YSS. Lipid was greatly metabolized in germination, which explained why the protein relative percentage in dried soybean sprout was higher than that in the corresponding soybean. Total phenolic compounds and saponin (mg/g soybean sprout, dry basis) had the same accumulation trend in soybean sprout with the increases in germination days. Aglycone isoflavones (genistein, glycitein, and daidzein) and daidzin showed an increased trend, whereas malonylgenistin and malonylglycitin showed a decreased trend with germination days for both GSS and YSS. The change in other isoflavones did not show definite trends. GSS had 20% more antioxidant activities than YSS (7‐d germinated soybean sprout). The increases in ORAC antioxidant activity suggest eating GSS may be more beneficial than GSS for promoting human health.     

Effect of Germination on Chemical Composition,Biochemical Constituents and Antinutritional Factors of Soya Bean (Glycine max) Seeds

The published scientific data concerning the effects of germination on chemical composition, biochemical constituents and anti-nutritional factors of soya bean are reviewed. The amino acid profile did not change to a great extent; only a noticeable increase in aspartic acid was observed whereas there was a gradual decrease in the available lysine level and lipid content as germination progressed. Both the total protein content and the nonprotein nitrogen increased after 5 days of germination. Dietary fibres are partially degraded in germinated seeds. Germinated soya bean is an excellent source of ascorbic acid and riboflavin. Niacin contents increased distinctly after germination. Germination induced a reduction in lipase inhibitor activity. The galactosyl oligosaccharides drastically decreased in germinated seeds. After 4 days of germination, the activity of certain lectins decreased to 4% of that of ungerminated soya beans. The phytic acid in the seeds was degraded by the phytase activated during germination, thus increasing the availability of the minerals present in the germinated seeds. Germination can degrade both Kunitz soya bean trypsin inhibitor and the major Bowman–Birk soya bean trypsin inhibitor; the degradation is enhanced, if germination process lasts more than 4 days. © 1997 SCI.     

Changes in γ-aminobutyric acid content and related enzyme activities in Jindou 25 soybean (Glycine max L.) seeds during germination

In order to accumulate γ-aminobutyric acid (GABA), soybean seeds (cultivar Jindou 25) were germinated for 102 h at different temperatures (19, 25 and 32 °C). The content of GABA, glutamic acid and the activity of the glutamate decarboxylase (GAD) and GABA transaminase (GABA-T) in soybeans during germination were investigated. The results showed that the germination temperature and germination time had great influences on GABA content and the related enzyme activities in soybean seeds. As compared to raw soybeans, an increase in the content of GABA and glutamic acid was observed, as well as GAD activity in soybeans during germination, while germination at 32 °C was better for accumulating GABA in soybeans. The GABA-T activity first decreased and then increased at 19 °C and 25 °C, on the contrary, it first increased and then decreased sharply during germination at 32 °C. These results indicate that the increase of GABA content can be attributed to the changes of GAD and GABA-T activities rather than enough glutamic acid resulting from the degradation of protein during germination of Jindou 25 seeds. However, more assays need to be further performed with more soybean cultivars.     

Kinetic study of the antioxidant compounds and antioxidant capacity during germination of Vigna radiata cv. emmerald, Glycinemax cv. jutro and Glycine max cv. merit

The purpose of this study was to determine the antioxidant capacity and the content of antioxidant compounds in raw mung bean seeds and sprouts (Vigna radiata cv. emmerald) germinated for 2, 3, 4, 5 and 7 days and of soybean seeds of Glycine max cv. jutro germinated for 2, 3 and 4 days and of Glycine max cv. merit germinated for 2, 3, 4, 5 and 6 days. Antioxidant compounds, such as vitamin C and E, total phenolic compounds and reduced glutathione (GSH) were studied. Antioxidant capacity was measured by superoxide dismutase-like activity (SOD-like activity), peroxyl radical-trapping capacity (PRTC), trolox equivalent antioxidant capacity (TEAC) and inhibition of lipid peroxidation in unilamellar liposomes of egg yolk phosphatidylcholine (PC). The results indicated that changes in the contents of vitamin C, vitamin E and GSH depended on the type of legume and germination conditions. Sprouts of mung bean and soybeans provided more total phenolic compounds than did raw seeds. The SOD-like activity increased after germination of mung bean seeds for 7 days, by 308%, while no change was observed in sprouts of Glycine max cv. jutro and an increase was observed after 5 and 6 days of germination (∼20%) in Glycine max cv. merit. PRTC and TEAC increased during the germination process and retentions of 28–70% and 11–14%, respectively, for soybean, and 248% and 61%, respectively, for mung bean were observed at the end of germination. The inhibition of lipid peroxidation increased by 389% in 5–7 days’ germination of Vigna radiata cv. emmerald sprouts, and 66% in Glycine max cv. merit sprouts whilst, in Glycine max cv. jutro, germination did not cause changes in lipid peroxidation inhibition. According to the results obtained in this study, germination of mung bean and soybean seeds is a good process for obtaining functional flours with greater antioxidant capacity and more antioxidant compounds than the raw legumes.     

Germination improves the functional properties of soybean and enhances soymilk quality

The effects of soybean variety and germination time on structural changes, antinutritional factor content, antioxidant activity of germinated soybean, and on the functional properties of soymilk were comprehensively investigated. The results showed that the antioxidant activity increased with increasing germination time. The content of antinutritional factors decreased with increasing germination time. Soybean varieties with the lowest tannin and trypsin inhibitor content were DN690 and HJ1. Lipoxygenase activity and phytic acid content showed no significant differences among soybean varieties. The content of α-helices and β-turns in soybean protein decreased with increasing germination time, while the content of β-sheets was increased. Soybean protein was progressively broken down into smaller molecular peptides during the germination process. The digestion and content of soluble protein in soymilk increased with germination. In summary, we show that germination is an effective, cheap, and green method that improves the functional properties of soybean and soymilk.     

发芽大豆的营养价值及其复合乳生产技术

研究了大豆籽粒在发芽过程中营养成分变化和用发芽大豆为原料生产豆乳与牛乳复合的工艺。大豆在发芽过程中 ,随着胚根长度的增加 ,可溶性蛋白质呈先升后降的趋势 ,游离氨基酸始终在增加 ,脂肪和植酸则持续下降。大豆胚根长度 2mm时 ,可溶性蛋白质增加量和植酸减少量分别为浸泡结束时的 5 6 88%和 45 99% ;胚根长度 15mm时 ,游离氨基酸比浸泡结束时增加 1 0 3倍。发芽大豆用质量分数 0 2 %的NaHCO3 溶液 80℃下处理 2min ,经清洗、去皮、热磨、滤浆和煮沸等处理 ,发芽豆乳的豆腥味轻微 ;豆乳与牛乳以体积比 4∶6的比例制成的复合乳营养合理 ,风味协调