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探讨了反应温度、滴定酸度、胃蛋白酶添加量、CaCl2加入量等因素对胃蛋白酶凝乳作用的影响规律,确定了用胃蛋白酶生产干酪时的主要工艺参数,反应温度39℃;滴定酸度24T;CaCl2加入量0.015%;加酶量随酶活而定。 相似文献
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不同因素对羔羊皱胃酶凝乳活性的影响 总被引:10,自引:1,他引:10
研究结果表明,羔羊皱胃酶最适凝乳温度为45℃;35℃以上热处理对酶凝乳活性有不同程度的损失,60℃热处理10 min活性完全丧失;pH值为5~8时凝乳活性随乳pH值的降低而增强,酶在pH2.5~7.5之间处理20h凝乳活性稳定;Ca2+具有明显的促凝作用;底物浓度对酶活性的影响符合米氏规律。 相似文献
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Mangal S. Rathore S. Shekhawat G. Kaur R. P. Singh N. S. Shekhawat 《Journal of Sustainable Forestry》2013,32(8):727-746
Withania coagulans (Stocks) Dunal (Solanaceae), popularly called vegetable rennet, is a critically endangered and highly valued medicinal plant. Overexploitation and reproductive failure forced the plant species toward the verge of complete extinction. We describe here the development of a simple, rapid, and cost effective in vitro micropropagation system for W. coagulans for mass-scale production of true-to-type plantlets using nodal shoot segments. Exactly 95.5 ± 0.34% explants responded within 8–10 days (d) and produced multiple shoot buds (4.1 ± 0.10 shoots of 2.95 ± 0.15 cm length) on 0.8% agar-gelled Murashige and Skoog's (MS) basal medium supplemented with 8.88 μM 6-benzylaminopurine (BAP), 0.57 μM indole-3-acetic acid (IAA), and additives (100 mg L?1 L-ascorbic acid, 25 mg L?1 each citric acid, adenine sulphate, and L-arginine). The shoots in cultures were multiplied by repeated transfer on MS medium with 4.44 μM BAP, 0.57 μM IAA, and additives. Further cultures were multiplied on a large-scale through the subculturing of shoot clumps differentiated in vitro, on MS medium supplemented with 1.11 μM BAP, 0.57 μM IAA, and additives. Maximum number (19.1 ± 0.28) of healthy (6.15 ± 0.25 cm) and viable shoots differentiated on this medium. The microshoots were rooted both in vitro and ex vitro. Exactly 67.3 ± 1.01% microshoots rooted in vitro within 25–30 d on agar-gelled half-strength MS salts supplemented with 29.52 μM indole-3-butyric acid (IBA) and 200 mg L?1 of activated charcoal (AC). Alternatively, 73.8 ± 0.65% cloned shoots rooted on sterile soilrite (soilless compost and soil conditioner) under ex vitro conditions after pulse treatment with 2.46 mM IBA for 300 s. The clones of W. coagulans were hardened in a greenhouse within 40–45 d by slow and gradual exposure of plantlets from high relative humidity (RH; 70–80%) and low (26 ± 2°C) temperature to low RH (40–50%) and high (34 ± 2°C) temperature. The hardened plantlets were transferred to soil and stored in agro-net house with more than 90% survival rate. Replacement of pure and laboratory grade sucrose with commercial grade sugar, use of less expensive commercial grade agar-agar in culture medium, higher rate of shoot proliferation, single step ex vitro rooting, and hardening of plantlets in the greenhouse are advantageous features of the protocol. The micropropagation protocol defined here is reproducible, easy to follow, and would be helpful in large-scale restoration programs through true-to-type mass-multiplication of W. coagulans. 相似文献
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以西农莎能奶山羊的新鲜奶为原料 ,用微生物酶、牛皱胃酶和胃蛋白酶等 3种凝乳酶加工硬质干酪 ,检测其不同成熟期细菌总数、乳酸菌、大肠菌群、酵母和霉菌含量的变化 ,并对不同成熟期间的干酪进行感官综合评定。结果表明 ,微生物酶加工的干酪 ,在成熟第 60天其品质达到优良 ,而另 2种凝乳酶加工的干酪 ,在成熟第 90天其品质可定为优良。数据统计分析表明 ,不同凝乳酶加工的干酪 ,在其成熟期间各种微生物变化规律以及干酪品质明显不一致 ,并且干酪品质与微生物的数量和种类密切相关 相似文献
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以关中奶山羊羔羊皱胃为原料,分别用pH4.5,5.4和6.0提取液提取羔羊皱胃酶,并用L9(34)正交试验研究了不同pH提取液对皱胃酶提取效果的影响。结果表明,pH5.4提取液的提取活性最高,pH6.0提取液次之,pH4.5提取液最低;其最佳技术参数为:提取液pH5.4,NaCl质量浓度80g/L,提取温度30℃,皱胃质量与提取液体积之比为1∶20;提取时间48h。 相似文献
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介绍了内蒙古骑士股份有限公司切达干酪的生产经验和切达干酪的加工工艺,以及在生产中的关键控制点。对切达干酪的生产工艺在理论上进行了探讨。 相似文献
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牦牛“曲拉”干酪素凝乳酶的选择及工艺参数优化 总被引:1,自引:0,他引:1
以“曲拉”为原料,研究不同酶在凝乳酶干酪素制作中的应用效果,通过L9(34)正交试验对皱胃酶、木瓜凝乳酶、微小毛霉凝乳酶3种酶最佳工艺参数进行筛选,结合生产成本,优选出微小毛霉凝乳酶为生产凝乳酶干酪素的酶制剂,其最佳工艺条件为酶浓度3.75 mL/g,pH 7,温度55℃,CaCl2添加量12 g/kg。制品出品率73.49%,感官得分9.49,蛋白质含量85.25%,灰分7.23%,脂肪0.45%,符合QB/T3780-1999标准要求。 相似文献
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以羔羊皱胃为原料,研究了硫酸铵和食盐盐析法纯化羔羊皱胃酶的工艺条件,系统分析了食盐饱和度、pH、盐析温度以及盐析时间对羔羊皱胃酶纯化效果的影响。结果表明,硫酸铵不适宜用于盐析羔羊皱胃酶,而食盐是羔羊皱胃酶适宜的盐析剂。食盐盐析羔羊皱胃酶的适宜盐析条件为:食盐饱和度55%~65%,pH 4.00~4.60,盐析温度4℃,盐析时间16 h。 相似文献