浓缩型乳酸菌发酵剂制备中几个技术关键问题的探讨

对浓缩型乳酸菌发酵剂制备中菌株的选择、菌体增殖培养、细胞浓缩分离、生物保藏等技术关键问题进行了探讨，轻期为进一步发展浓缩型乳酸菌发酵剂提供依据。     

浓缩乳酸菌发酵剂的制备

本文着重叙述国外四种制备乳酸菌浓缩发酵剂的方法，即：离心分离法、化学中和法、缓冲盐法及渗析法，其特点及存在的问题，以促进我国开展浓缩乳酸菌发酵剂的研究和生产。     

超浓缩乳酸菌发酵剂研究进展

超浓缩乳酸菌发酵剂研究进展□周晓宏廖永红０前言发酵剂制备对于乳酸菌发酵制品是非常重要的。传统的乳酸菌发酵剂生产利用原始菌种进行活化复壮，再进行扩大培养而成，制备过程比较复杂，且容易造成污染，菌种质量不易控制，特别是中小型发酵乳制品厂，因生产条件简陋...     

乳酸菌冻干发酵剂制备工艺的研究

对乳酸菌冻干发酵剂的制备工艺进行了初步探索，对乳酸菌液体摇瓶培养中的参数和超滤浓缩特性参数进行了测定，确定了发酵剂冻干制备的工艺参数。在培养液中添加适量的碳酸钙，经过40℃、120r／min、15h的摇瓶培养，采用超滤法对摇瓶培养液进行菌体浓缩，然后将浓缩液进行冷冻干燥，即可得到冻干乳酸菌发酵剂。     

提高培养液中乳酸菌数的方法探讨

乳酸菌在发酵食品中应用非常广泛,发酵乳制品主要依靠添加乳酸菌类发酵剂进行发酵.要得到较高含菌量的发酵剂,首先应该提高培养液中乳酸菌数,以保证后续浓缩干燥等工艺的实施.概述了国内外制备直投式发酵荆工艺中提高培养液中乳酸菌菌数的方法,以及行业发展前景及趋势.     

浓缩型乳酸菌发酵剂的工业化生产

对乳品发酵剂工业化生产中的重要技术，诸如高活力菌体的增殖培养、发酵过程控制与分析、细胞富集和生物保存等问题进行了探讨．以期为我国进一步发展浓缩型乳酸菌发酵剂提供理论依据。     

乳酸菌发酵剂浓缩培养的研究

为制备高效浓缩乳酸菌发酵剂,通过综合运用复合生长培养基、缓冲盐法及化学中和法,对乳酸菌的浓缩培养进行了研究。试验结果表明,以 12％ NFM＋ 0.3％酵母膏＋ 0.1％ Tween 80作为复合生长培养基,加 0.5％ K2HPO4作为缓冲盐,接种量为 2％ (嗜热链球菌∶保加利亚乳杆菌 =1∶ 1),培养温度 42℃,培养过程用 30％ Na2CO3溶液作中和剂,将 pH值控制在 6.3,培养 6～ 7 h后,可使乳酸菌的活菌数达到 5.89× 109 mL－ 1。与普通的液体发酵剂相比,获得了显著的浓缩效果。     

可迅速开发新产品的高度浓缩乳酸菌

克里斯契耶享塞公司开发生产并在市场推出了冻结及颗粒状的高度浓缩乳酸菌产品“梯兰克特巴特塞特”。这是一种将乳酸菌发酵剂制成分别供奶酪、酸奶、酒类和面包等生产用的不同类别的发酵型商品，现在在日本由野泽组公司经营专供奶酪、酸奶等乳制品用的高浓度乳酸菌发酵剂；由日本希别尔海戈拿公司经营葡萄酒和面包用制品。     

酸奶发酵剂的研究进展

酸奶发酵剂一般由两种乳酸菌组成：嗜热链球菌和保加利亚乳杆菌。论述了酸奶发酵剂的发展现状、种类及制备方法,并对其前景进行展望。     

发酵香肠乳酸菌发酵剂筛选标准

乳酸菌是发酵香肠最重要的发酵剂菌种。本文介绍了发酵香中乳酸菌的作用,乳酸菌发酵剂的发展历史,着重探讨了发酵香肠乳酸菌发酵剂筛选标准。     

乳酸菌对中国传统主食馒头质量的影响

传统馒头发酵剂由多种微生物群体组成,乳酸菌是馒头传统发酵剂中的重要微生物类群,其种类和数量与馒头的品质存在内在联系。该文针对馒头传统发酵剂中乳酸菌菌群的发展过程以及乳酸菌发酵与馒头品质的关系进行了综述,为馒头发酵剂的研究提供参考。 关键词：中图分类号：TS211.4 文献标识码：A 文章编号：0254-5071（20１5）11-0010-04 doi:     

Lactic acid starter and probiotic bacteria: a comparative “in vitro” study of probiotic characteristics and biological barrier resistance

Probiotic characteristics (deconjugation of bile salts, hydrophobicity and β-galactosidase activity) and the resistance to biological barriers (gastric juice and bile salts) of 24 strains of lactic acid starter bacteria (Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and Lactococcus lactis) and 24 strains of probiotic bacteria (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus and bifidobacteria) were compared. Among the probiotic bacteria tested, Lactobacillus acidophilus was the most interesting species since it showed high values of resistance to gastric juice and bile, hydrophobicity and β-galactosidase and bile salts deconjugation activities. Bifidobacterium bifidum strains showed the same behavior, although the values of the parameters investigated were slightly lower than those obtained for Lactobacillus acidophilus. On the other hand, it was demonstrated that Lactobacillus delbrueckii subsp. bulgaricus was the lactic acid starter species with the best probiotic characteristics among the starter species assessed. It was resistant to gastric juice and bile, and showed high values for β-galactosidase activity. On the other hand, lactic acid starter bacteria showed hydrophobicity values similar to or higher than those obtained for the strains of the Lactobacillus casei . According to the results found, the total probiotic value of a fermented dairy product should take into account not only the intestinal probiotic cultures used in the formulation but also the probiotic contribution of the lactic acid starter microflora.     

直投式发酵剂生产四川泡菜的研究

通过分析接入乳酸菌直投式发酵剂和自然发酵四川泡菜发酵过程中亚硝酸盐含量、乳酸菌菌数和产品品质的动态变化,确定直投式菌剂发酵泡菜时的菌粉添加量和食盐用量。结果表明:添加4%食盐,接入0.04%直投式发酵剂,室温25℃,发酵7d后制得的泡菜酸甜适口,色泽好。添加到直投式发酵剂终产品中的亚硝酸盐含量显著低于自然发酵组,仅为2.11μg/mL,且其乳酸菌菌数远高于自然发酵组,肠膜明串珠菌和植物乳杆菌菌数分别达到6.42×107cfu/mL和3.13×107cfu/mL。     

泡菜乳酸菌生产干酪工艺研究

对泡菜中乳酸菌进行了初步分离纯化,共筛选出4种菌株,对这4种菌株进一步进行了发酵性能研究和凝乳实验,选择出优良两种菌株,并应用于新鲜软质干酪的制作,采用L9(34)正交实验的方法,研究了不同发酵剂菌株添加比例、发酵温度、切割pH值对成品干酪滋味口感、色泽的影响,确定了该产品生产的最佳配方和工艺条件:菌种比为菌株8与菌株12比为1∶1(质量比),发酵剂添加量为3%(质量分数),发酵温度为37℃,切割pH值为4.6。     

甘肃天祝牧区酸奶发酵剂发酵性能的研究

将从甘肃天祝牧区采集的酸奶样品及兰州市几种市售酸奶制作为酸奶发酵剂，对比它们的发酵性能．牧区酸奶发酵剂性能较优。由牧区酸奶发酵剂中分离得到的几株乳酸茵产酸能力及产黏能力较好，其发酵凝乳的温度范围较宽。     

肉制品发酵剂的筛选与发酵特性的研究

以MRS培养基为基础培养基,从自然发酵香肠和自制腌肉中分离、筛选出三株乳酸菌(F1、F2、F3),对其生化特性、发酵特性、生长状况、产酸能力、致死温度及菌株间的拮抗性进行研究,结果表明:3株乳酸菌均符合肉制品发酵剂的要求,可以作为肉制品发酵剂;菌株F1和F3,F2和F3可以作为肉制品的混合发酵剂.     

On-farm implementation of a starter culture for improved cocoa bean fermentation and its influence on the flavour of chocolates produced thereof

Cocoa bean fermentations controlled by means of starter cultures were introduced on several farms in two different cocoa-producing regions (West Africa and Southeast Asia). Two starter culture mixtures were tested, namely one composed of Saccharomyces cerevisiae H5S5K23, Lactobacillus fermentum 222, and Acetobacter pasteurianus 386B (three heaps and one box), and another composed of L. fermentum 222 and A. pasteurianus 386B (seven heaps and one box). In all starter culture-added cocoa bean fermentation processes, the inoculated starter culture species were able to outgrow the natural contamination of the cocoa pulp-bean mass and they prevailed during cocoa bean fermentation. The application of both added starter cultures resulted in fermented dry cocoa beans that gave concomitant milk and dark chocolates with a reliable flavour, independent of cocoa-producing region or fermentation method. The addition of the lactic acid bacterium (LAB)/acetic acid bacterium (AAB) starter culture to the fermenting cocoa pulp-bean mass accelerated the cocoa bean fermentation process regarding citric acid conversion and lactic acid production through carbohydrate fermentation. For the production of a standard bulk chocolate, the addition of a yeast/LAB/AAB starter culture was necessary. This enabled an enhanced and consistent ethanol production by yeasts for a successful starter culture-added cocoa bean fermentation process. This study showed possibilities for the use of starter cultures in cocoa bean fermentation processing to achieve a reliably improved fermentation of cocoa pulp-bean mass that can consistently produce high-quality fermented dry cocoa beans and flavourful chocolates produced thereof.     

甜高粱茎秆袋装青贮研究

采用袋装室温堆放发酵方式,通过测定料温、pH值、乳酸菌数、粗蛋白、残糖等指标,对比4种不同处理对甜高粱秸秆发酵效果的影响。结果表明,用菌剂R2J1处理甜高粱秸秆具有产酸适宜、乳酸菌数、蛋白增量明显等优点。整个发酵过程中,平均发酵料温始终高于环境温度4.3 ℃;发酵18 d时,饲料中乳酸菌数达1.2×1010个/g,此时饲料pH值为4.5,蛋白含量为9.89%,比发酵前增加了27.44%,各项指标均优于其他菌剂发酵结果,表明R2J1菌剂适用于西北高寒区甜高粱秸秆袋装青贮。