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71.
通过米曲霉固态发酵花生粕,结合酶解与冷冻干燥技术,制备花生肽。促生长实验表明,以0.5%添加分子量小于3ku的花生肽对保加利亚乳杆菌的促生长作用更为明显,其中乳杆菌的活菌数可提高1个数量级,凝乳效果改善,乙醛含量增加。比较氨基酸组成结果表明,该技术可有效提高氨基酸含量,改善氨基酸组成,乳杆菌生长必需的氨基酸含量达33.61~226.33mg/g。 相似文献
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采用益生菌混合物AST和TLB分别在42℃进行豆乳的发酵,在发酵豆乳的发酵和贮存过程中(4℃下28d),观察pH值和活菌数的变化情况。在AST益生菌混合物(嗜酸性乳杆菌,双歧杆菌和嗜热链球菌)的培育下,42℃下发酵时间减少到8h。但嗜酸性乳杆菌在冷藏的过程中生存状态较差,其活菌数在冷藏后一周后未达到标准。将豆乳在42℃下用TLB益生菌(嗜热链球菌,保加利亚乳杆菌和动物双歧杆菌乳酸亚种Bb12)进行发酵,结果发酵时间缩短到4h,双歧杆菌活菌数目的对数增加了约一半,而且经过28d的冷藏,细菌数仍然维持在107 CFU/mL以上。 相似文献
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ZAHRA GHASEMPOUR MOHAMMAD ALIZADEH MAHMOUD R BARI 《International Journal of Dairy Technology》2012,65(1):118-125
A Box‐Behnken design was applied to optimise the viability of Lactobacillus acidophilus and Bifidobacterium bifidum in probiotic yoghurt containing a novel exudative Zedo gum. The effect of incubation temperature, probiotic inoculation rate, storage time and Zedo gum concentration on quality indices of the yoghurt were explored. With respect to probiotics viability, probiotic inoculation rate was the most important factor followed by the storage time. Zedo gum did not show any significant effect on probiotics viability. The optimum conditions of probiotic yoghurt production were as follows: probiotic inoculation level, 12.8 g/100 kg of milk; incubation temperature, 41.6 °C; and Zedo gum concentration, 0.13%. 相似文献
77.
Marilsa S. S. Santini Evelyn C. Koga Davi C. Aragon Elsa H. W. Santana Marcela R. Costa Giselle N. Costa Lina C. Aragon‐Alegro 《Journal of food science》2012,77(11):M604-M608
Abstract: A dried tomato‐flavored probiotic cream cheese (P) containing Lactobacillus paracasei Lpc‐37 was developed for the purpose of this study. The same product, but without probiotic addition (C) was used as control. Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris were used as lactic starter cultures. Chemical composition analyses and sensory tests were performed on days 1 and 7, respectively. Titratable acidity, pH value and L. paracasei population were determined every 7 d during the refrigerated storage (21 d) of the cream cheeses. The experiment and analyses were performed in triplicate, using standard methods. Probiotic population remained greater than 107 CFU/g throughout the storage period, thereby characterizing the product as potentially probiotic. Cream cheeses C and P did not differ on the sensory tests, both obtaining good overall acceptance by the consumers, of which 82.6% stated that they certainly or probably would buy the product. Practical Application: Lactobacillus paracasei Lpc‐37 is a probiotic bacterium and clinical studies have shown that this microorganism beneficially affects its host. In general, dried tomato‐flavored products and cream cheese are products with good acceptance by the consumers. Thus, regular consumption of the probiotic cream cheese developed in this study may have positive effects on health and well being of people if incorporated into their diet. 相似文献
78.
A new amylolytic strain of Lactobacillus paracasei able to convert starch directly into L ‐(+)‐lactic acid (LA) was isolated. The identification of the by 16S rDNA sequencing proved that this strain, B41, is the first amylolytic representative of Lactobacillus casei group. The amylase activity assay revealed that L. paracasei B41 produced extracellular amylolytic enzyme, reaching 62 U/mL in the cell‐free supernatants. The optimal conditions for its action were pH 5.0 and temperature 45°C. The gene amy1 (1779 bp) encoding the putative B41 amylopullulanase was cloned, sequenced, and analyzed. The deduced protein contained a leader peptide of 28 amino acids and a mature peptide of 564 amino acids. Compared to the amylases of closely related species, B41 enzyme had several amino acid substitutions. An inducible control at amy1 expression was demonstrated. The starch fermentation abilities of L. paracasei B41 were studied in batch processes performed with and without pH control. The highest amount of LA from starch was obtained during 48 h fermentation from 40 g/L substrate at pH maintained at 5.0–37.3 g/L. In addition, 93.3% starch conversion into LA and the highest reported productivity for 24 h were achieved – 1.30 g/L/h. 相似文献
79.
模拟人体消化道环境,即在人工胃液、肠液的环境下对植物乳杆菌LPb1的耐受性进行研究,结果表明:在37℃条件下,用人工胃液处理3h,收集的菌体再转入人工肠液处理3h,最后测得菌株存活率仍达88.6%。LPb1与一株嗜热链球菌混合发酵脱脂乳,与单菌发酵相比,混合菌产酸效果较好,发酵乳制品具有良好的持水性能,且发酵完成后,4℃冰箱贮存后酸化程度缓慢。通过单因素和响应面分析,混合发酵最佳发酵条件为:接种量4.45%、发酵时间8.53h、发酵温度40.40℃。 相似文献
80.
乳酸杆菌HD11发酵刺五加对紫丁香苷及异嗪皮啶含量的影响 总被引:3,自引:0,他引:3
采用高效液相色谱法对刺五加发酵前后紫丁香苷及异嗪皮啶的含量进行检测,研究乳酸杆菌HD11发酵刺五加对紫丁香苷及异嗪皮啶含量的影响。结果表明:刺五加经乳酸杆菌HD11发酵后紫丁香苷含量显著降低,而在其附近位置出现了新物质;乳酸杆菌HD11发酵刺五加根、茎后异嗪皮啶含量分别由发酵前的0.08、0.05mg/g提高到0.14、0.15mg/g。刺五加发酵后紫丁香苷含量降低,是由于紫丁香苷在乳酸杆菌HD11的作用下降解转化为其他物质,而异嗪皮啶含量的提高有利于提高活性成分的利用度。 相似文献