Effect of Fermentation by Pure Cultures of Yeasts and Lactobacilli on Phytic Acid and Polyphenol Content of Pearl Millet

Single and mixed pure culture fermentations of pearl millet flour with yeasts and lactobacilli, namely, Saccharomyces diastaticus, Saccharomyces cerevisiae, Lactobacillus brevis and Lactobacillus fermentum, at 30^oC for 72 hr brought about a significant reduction in phytic acid and polyphenols which were present in considerable amounts in pearl millet flour. Reduction in phytic acid was more pronounced than that in the polyphenols.     

Effect of Temperature and Fermentation Time on Phytic Acid and Polyphenol Content of Rabadi— A Fermented Pearl Millet Food

Rnbadi was prepared by fermenting a mixture of pearl millet flour and butter milk for three periods of time (3, 6 and 9 hr) at four temperatures (35°, 40°, 45° and 50°C). Temperature had little influence on degradation of either phytic acid or polyphenol content. At all temperatures the phytic acid and polyphenol content decreased with an increase in fermentation time. Nine hour fermentation resulted in maximum reduction of phytic acid (27–30%) as well as total polyphenols (1–12%) at all temperatures. Phytic acid was reduced to a greater extent than polyphenols.     

工艺参数对发芽糙米中植酸含量的影响

研究发芽糙米生产过程中糙米所含抗营养因子植酸的变化规律,以发芽温度、发芽时间、浸泡时间、赤霉素浓度等工艺参数对产品植酸含量的影响进行了正交试验,试验结果表明:发芽温度和发芽时间对植酸含量的影响显著,发芽温度的提高和发芽时间的持续使糙米中植酸的含量逐步下降;通过发芽降低糙米植酸含量的最佳工艺参数组合为:发芽温度36℃、发芽时间34 h、浸泡时间12 h、赤霉素(GA3)浓度0.30 mg/L,此条件下发芽糙米产品中的植酸含量为3.22 mg/g.     

Effect of Germination and Fermentation on in vitro Starch and Protein Digestibility of Pearl Millet

Germination of pearl millet grain for 24 hr significantly improved its in vitro starch and protein digestibility. Fermentation of pearl millet sprouts by mixed culture combinations of yeasts and bacteria (Saccharomyces diastaticus and Lactobacillus brevis; Saccharomyces diastaticus and Lactobacillus fermentum; Saccharomyces cerevisiae and Lactobacillus brevis; and Saccharomyces cerevisiae and Lactobacillus fermentum) resulted in a significant increase in protein and starch digestibility. The pearl millet sprouts fermented with mixed culture containing S. diastaticus and L. brevis had the highest in vitro starch digestibility, while the sprouts fermented with the culture containing 5. cerevisiae and L. fermentum had the highest in vitro protein digestibility.     

Effect of Germination on Phytic Acid, Protein and Fat Content of Rapeseed

Rapeseed was germinated over a 7-day period and the changes in phytic acid, protein and fat contents were monitored. Two-day germination period reduced the phytic acid by 13% and slightly increased the fat and protein by 6 and 4%, respectively. A 65% decrease in phytic acid, 10% increase in protein and 46% decrease in fat were observed after 7 days of germination. The free fatty acid values increased from 1 to 120. While reduction in phytic acid and increase in protein are desirable, the reduction in fat and its increased hydrolysis to free fatty acids after 7 days may be considered detrimental if rapeseed oil is to be extracted for commercial purposes.     

植酸对黄酒酵母菌607生长和发酵性能影响的研究

添加植酸于黄酒酵母生长发酵基质中，研究植酸对黄酒酵母生长和发酵的影响，得出如下结论：(1)最适植酸添加浓度为0．10％，至主发酵结束，酒精度最大可提高13．16％；(2)植酸能促进黄酒酵母细胞增殖，使酵母提前进入对数生长期，提高出芽率，降低死亡率，并表现出较好的同步性，从而加快发酵速度；(3)植酸使黄酒酵母的耐酒精度从16％提高到20％；(4)黄酒醪中添加植酸，发酵周期缩短且各项理化指标均有较大改善，从而提高了黄酒产量和质量。     

Amino Acid Metabolism by Yeasts and Lactic Acid Bacteria during Bread Dough Fermentation

Metabolism of 22 free amino acids (AA) during fermentation(early and later steps) of wheat dough samples started with pure and associated cultures of yeast and lactic acid bacteria, and commercial compressed yeast (CY) were investigated. Unfermented and fermented straight doughs were studied byReversed-Phase HPLC of their dansyl derivatives. Used as starters were strains of Saccharomyces cervisiae, Lactobacillus brevis, Lactobacillus plantarum and Enterococcus faecium. Statistical data analysis indicated clustering of samples with yeast and samples without yeast (including uninoculated doughs) respectively, based on rate of metabolism of acidiC., basiC., aliphatic and aromatic A A. Differences in AA metabolism during the later fermentation step (DF2) categorized bacterial starters into groups according to balance between degree of assimilation(D F2<0) and exoproteolytic release(DF2>0) of amino acids.     

发酵法降解油菜籽废水中植酸的工艺研究

水酶法提取菜籽油工艺产生了大量废水,其中含有丰富的水溶性蛋白、碳水化合物和抗营养因子。为了降解水中的抗营养物质植酸,利用筛选出的酵母菌对其进行发酵,并通过正交试验优化培养条件,得出K酵母在32℃,pH 7条件下培养36 h,可将废水中植酸降解87%,从而为废水的循环利用或达标排放打下了基础。     

Effects of Germination of Wheat,Oats, and Pearl Millet on Alpha-Amylase Activity and Starch Degradation

Hard red winter wheat, oats, and pearl millet were germinated at 15°C for periods up to 14 days. Endosperm areas in kernels fractured with a razor blade and starches isolated from the malted flours were examined with a scanning electron microscope to determine the morphology of starch granules and the nature of α-amylolytic attack on granules. Free sugars content, damaged starch content, and α-amylase activity of the flours were determined to establish relationships between physical changes in the cereal grains and formation of α-amylase during germination. Starch granules in the three cereals were degraded during germination by α-amylase accompanied by production of free sugars and increases in the damaged starch of flours milled from the germinated grains. The cementing material embedding starch granules in endosperms of wheat and oats decreased and disappeared during germination; these changes were not obvious in germinated millet endosperm. Amorphous-appearing material seemed to cover starch granules in the endosperm of wheat and oats during later stages of germination, but were not observed in the isolated starch granules. Although wheat starch granules had the highest α-amylase activity, this enzymic degradation was less than expected. Enzymic attack was evidenced as channels or pits on the surfaces of wheat and millet starch granules. Compound oat starch granules were relatively resistant to enzymic attack and no evidence of erosion of the granule surface was observed; small granula were released from the compound granules during germination. The most extensive degradation was obtained with millet starch, appearing as discrete holes leading to the interior of the granule. Concentric shells were visible in the interior of wheat and millet starch granules, but were not observed in oat starch granules.     

植酸对辣椒保鲜效果的研究

以鲜辣椒为试材,用浓度0.4%、0.6%、0.8%的植酸溶液浸泡30s,取出晾干,室温下袋装贮藏,研究植酸对辣椒的保鲜效果。结果表明,经过植酸涂膜处理,能降低辣椒的失重率、红果率、腐烂率,减缓辣椒VC和可溶性固形物的损失,具有良好地保鲜效果。其中浓度为0.6%的植酸溶液涂膜处理辣椒保鲜效果较好,室温下贮藏可延长辣椒的货架期。     

酶法降低糙米植酸含量工艺条件的优化

以糙米为研究对象，借助超声波强化传质过程，利用植酸酶降低糙米中植酸的含量，研究液料比、温度、pH值对植酸水解反应的影响，采用中心组合试验方案设计和响应面分析方法对植酸水解的工艺条件进行优化。研究结果表明，植酸水解工艺的优化条件为：pH值6．5，温度为53℃，液料比为10。     

Mixed Culture Fermentation of Cucumber Juice with Lactobacillus plantarum and Yeasts

Saccharomyces cerevisiae and Saccharomyces rosei were tested for use in mixed culture fermentation of cucumber juice with Lactobacillus plantarum. Extent of sugar utilization and the ratio of products formed (lactic acid:ethanol) were influenced by time of inoculation and cell numbers of each microorganism. Sugar fermentation was complete within 6 days at 28°C when similar numbers of bacteria and yeasts were added simultaneously, or when yeasts were added before the bacteria. Sugar remained when only L. plantarum was added, or when yeasts were added in low numbers. Glycerol was produced when yeasts were present, the concentration being directly related to NaCl concentration. Results suggest advantageous uses of yeasts to complete fermentation and to modify acidity.     

四株乳酸菌纯种发酵泡椒的研究

以红圆椒为原料,选用植物乳杆菌、嗜酸乳杆菌、食果糖乳杆菌和肠膜明串珠菌等4株乳酸菌纯种发酵泡椒,对比自然发酵.以发酵周期、产乳酸量、pH值、OD值作为考察菌株发酵特性的指标,利用质构仪测定泡椒硬度,并结合感官评价对泡椒品质进行评定.结果表明:较自然发酵泡椒组而言,5％接种量的食果糖乳杆菌组发酵周期最短,发酵到第3天时的OD值为0.851,比自然发酵高出近1倍,对于泡椒硬度的保持也相对较好;发酵5天后,其硬度仍能保持在41.327 N,并且产生了良好的发酵风味.通过感官评价,接种量为5％的食果糖乳杆菌发酵泡椒具有风味较好,品质优良,口感上佳,色泽自然等特点.     

不同浓度植酸处理对油桃保鲜效果的影响

将油桃分别浸入浓度为0．05％、0．10％、0．15％的植酸溶液中30s,晾干装袋后置于室温下贮藏,定期测定油桃的理化指标,研究不同浓度植酸溶液涂膜处理对油桃的保鲜效果。结果表明,植酸用于油桃保鲜,可以延缓VC降解、降低糖酸损失、减少失重、防止腐烂、保持硬度、抑制呼吸、延长油桃的贮藏期,其中浓度为0．10％的植酸溶液涂膜处理保鲜效果较明显。     

发芽条件提高南瓜籽中亚油酸含量的研究

以发芽率为80%的南瓜籽为原料,采用超临界CO2萃取法提取南瓜籽油,采用气相色谱法对南瓜籽油中的亚油酸含量进行测定,研究发芽条件对南瓜籽中亚油酸含量的影响,通过对发芽前后提取的南瓜籽油中亚油酸的含量进行对比.结果表明:南瓜籽发芽条件为:当发芽温度为28℃,发芽时间为4 d,浸泡时间为5 h,其游离脂肪中的亚油酸含量提高了13.23%.     

大豆植酸分离方法对测定结果的影响

探讨了大豆植酸的浸提、离心和离子交换条件对其测定结果的影响。大豆经磨粉、过筛后 ,用 0 3 5mol/LHCl 0 7mol/LNa2 SO4溶液能充分提取出大豆的植酸 ;沸水浴后40 0 0r/min离心 10min可除去蛋白质 ;阴离子交换时 ,依次用 15mL蒸馏水、15mL 0 0 5mol/LNaCl淋洗 ,而后用 2 0mL 0 7mol/LNaCl以 1 0mL/min的速度洗脱 ,洗脱液的植酸加标回收率达到 98%以上 ;4个大豆样品中植酸测定结果的相对标准偏差分别为 1 2 3 %、4 0 5 %、1 5 3 %和 1 83 %。     

不同酵母对面团发酵特性及馒头品质的影响

就不同酵母对面团发酵特性和馒头品质的影响进行了试验.通过比较不同酵母发酵面团的产气量和面团膨发状态,进而确定相同条件38℃,88%RH,酵母添加量0.8%,不同酵母的最适发酵时间,然后对其发酵的馒头进行感官评价和质构测定,结果显示:不同酵母发酵面团时的产气量和面团膨发状态不同,Y-1、Y-2、Y-3和Y-4的最适发酵时间依次为40、30、25和30 min.由感官评价和质构测定结果还得出结论:不同酵母显著影响馒头产品的感官评价总分,且感官评价和质构测定参数与其面团发酵性能相一致.     

Effect of Soda Leavening on Phytic Acid Content and Physical Characteristics of Middle Eastern Breads

The effect of soda (sodium bicarbonate) as a leavening agent on pH, phytic acid hydrolysis and physical quality of a fermentation model system and two popular Middle Eastern breads, Iranian taftoon and Pakistani naan (Arabic) were studied. Supplementing 0.2 and 0.4% soda invariably decreased phytic acid hydrolysis. In sour starter supplemented dough, phytic acid was reduced by 82% after 3 hr. However, when 0.4% soda and sour starter were added loss of phytic acid did not exceed 29%. Supplementing soda in taftoon and naan bread formula significantly lowered phytic acid hydrolysis during fermentation. Soda had no apparent improvement on physical quality of breads but increased the dough water absorption and lengthened the mixing time.     

A Research Note Effect of Natural Fermentation on the Extractability of Minerals from Pearl Millet Flour

Natural fermentation of pearl millet flour was carried out at 20°, 30°, 40°, and 50°C for 24, 48, 72, and 96 hr. The fermentation improved the HCI-extractability of minerals including calcium, zinc, iron, manganese and copper in pearl millet flour. The highest extractability of minerals was observed at 96 hr at all the temperatures.     

植酸对黄曲霉菌糖化酶活力的影响

通过添加不同浓度的植酸于黄曲霉菌（Aspergillus flavus)02-6-58培养基中,于不同生长时间、不同添加方式测定黄曲霉菌糖化酶活力,研究植酸对黄曲霉菌糖化酶活力的影响。结果表明：(1)加入植酸后其糖化酶活力均有很大提高。其最佳作用浓度范围是0．20％-0．25％,最大可提高44．32％;(2)在黄曲霉菌生长麸曲中添加植酸比在连续培养3代的斜面培养基中加入植酸糖化酶活力提高幅度更大;(3)比较黄曲霉菌生长曲线及产酶曲线,加入植酸后,其对数生长期提前3～4h,平衡期延长,从而提前进入产酶高峰期。