清酒乳杆菌对新疆酸驼乳发酵特性的影响

关于新疆酸驼乳研究已经表明,清酒乳杆菌存在于自然发酵酸驼乳中,但清酒乳杆菌的存在是否对酸驼乳发酵产生正面影响还未清楚。为此,本实验首先建立一种基于特有菌落形态与katA基因相结合的清酒乳杆菌检测方法,从而跟踪驼乳的发酵过程,用不含清酒乳杆菌酸驼乳和含有清酒乳杆菌的酸驼乳作为自然发酵剂分别接种新鲜消毒驼乳,结果表明,接种含有清酒乳杆菌的酸驼乳的新鲜驼乳其黏度随着时间延长而逐渐下降;相反接种不含清酒乳杆菌酸驼乳的新鲜消毒驼乳,其黏度随着时间延长而增高。进一步用分离自酸驼乳的清酒乳杆菌与6株其他乳酸菌分别接种新鲜消毒驼乳,结果表明:接种清酒乳杆菌的驼乳黏度均有下降;相反接种其他乳酸菌的驼乳黏度均有不同程度的增加。这一结果初步揭示了在低黏、奶香型传统驼乳发酵中清酒乳杆菌起重要作用。     

添加肉类蛋白对米酒乳杆菌生境适应相关基因表达的影响

米酒乳杆菌是常见的异型发酵乳酸菌,它常常用作肉类工业发酵剂。为了了解其在肉类环境中的生存状况,本文用定量PCR对米酒乳杆菌La22在添加肌浆蛋白和肌原纤维蛋白的培养基中生长时生境适应相关基因表达量进行分析。结果显示,在两种培养基中生长时,p H值均随时间的延长而下降,在添加肌浆蛋白的培养基略高于添加肌原纤维蛋白培养基。与对照相比,在添加肌浆蛋白培养基中的arc A、arc B、arc C、arc T以及添加肌原纤维蛋白培养基中的arc R基因表达量明显上调,其余几个arc基因也均上调,但不明显;压力相关基因lsa00513、usp4以及usp2在肌浆蛋白培养基中均明显上调;有6个ABC转运子基因在添加两种肌肉蛋白的培养基中表达量明显上调。结果表明米酒乳杆菌能通过能量转换与基因表达调节来适应含肉类蛋白的培养环境。     

Lactobacillus acidophilus Group Lactic Acid Bacteria Applied to Meat Fermentation

Lactobacillus acidophilus group bacteria (L. acidophilus, L crispatus, L. amylovorus, L. gallinarum, L. gasseri, L. johnsonii) , probiotic lactic acid bacteria, were applied to meat fermentation. Of six strains, L. gasseri (predominant lacto-bacilli in human intestinal tracts) JCM1131^T exhibited greatest fermentation performance in meats. This strain resisted gastric acid and bile, and would thus have no detrimental effects in the intestinal tract. Inoculation of the strain depressed the propagation of S. aureus cells and their enterotoxin production during meat fermentation. Results suggest probiotic lactic acid bacteria could be effectively utilized for meat fermentation to produce healthy meat products.     

植物乳杆菌和戊糖片球菌复合发酵牦牛肉工艺优化

酸化对鲜肉有一定的嫩化作用,利用植物乳杆菌和戊糖片球菌2 种益生菌复合发酵可以改善牦牛肉的嫩度。采用单因素试验和L9（34）正交试验设计,以pH值、剪切力和可溶性蛋白含量为评价指标,优化植物乳杆菌和戊糖片球菌复合发酵牦牛肉的工艺参数。结果表明：最佳工艺参数为发酵剂接种量1.0×106 CFU/g、发酵温度30 ℃、发酵时间18 h,在此条件下牦牛肉的pH值为5.02,剪切力为76.76 N,可溶性蛋白含量为52.02 mg/g。植物乳杆菌和戊糖片球菌复合发酵使牦牛肉的pH值降低,剪切力下降,可溶性蛋白含量增加,牦牛肉嫩度得到一定程度的改善。     

清酒乳杆菌对发酵风干肠品质的影响

该研究采用清酒乳杆菌（Lactobacillus sakei，L. sakei）作为发酵菌株制备发酵风干肠，研究其对发酵风干肠品质的影响，以自然发酵产品作为对照组，在发酵成熟过程中的第0、3、6、9天测定产品的菌落总数、乳酸菌数、pH值、水分含量、水分分布、嫩度、色差、过氧化物值（Peroxide Value，POV）、硫代巴比妥酸值（Thiobarbituric Acid Value，TBARS）、脂肪酸含量和感官评分等指标，研究发酵菌株对风干肠品质的影响。试验表明，L. sakei接种组的乳酸菌数和菌落总数显著高于对照组（P<0.05），L*值、a*和b*显著低于对照组（P<0.05）；L. sakei接种组在发酵终点时，水分含量降至32.15%，pH值降至4.41，保证了发酵风干肠的安全性；POV值和TBARS值显著低于对照组（P<0.05），表明L. sakei具有较好的抑制脂肪氧化作用；L. sakei接种组的总体可接受性更高，发酵后期酯类物质种类和含量均高于对照组。综上，L. sakei的添加改善了产品的品质和风味。     

臭鳜鱼源清酒乳杆菌的分离鉴定及其在臭鳜鱼发酵中的应用

利用含溴甲酚绿的MRS鉴别培养基,从传统臭鳜鱼中分离筛选到1 株乳酸菌,经形态学、生理生化实验以及16S rDNA序列分析鉴定为清酒乳杆菌,并命名为SMF-L5。清酒乳杆菌SMF-L5在MRS液体培养基中生长良好,14 h进入生长稳定期,活菌数最高可达7.0×109 CFU/mL,培养24 h后乳酸产量达10 g/L,最适培养条件为：培养温度30.9 ℃、初始pH 6.15、接种量1.94%。菌株SMF-L5具有耐受0.08 g/mL NaCl的能力,对大肠杆菌、金黄色葡萄球菌等菌株具有明显的抑制作用。接种清酒乳杆菌SMF-L5发酵的臭鳜鱼,比自然发酵臭鳜鱼具有更好的色泽、质构和风味品质。研究结果表明,臭鳜鱼源清酒乳杆菌SMF-L5可作为优良的乳酸菌发酵剂,在臭鳜鱼工业化生产中具有应用潜力。     

Study of the Lactobacillus sakei protective effect towards spoilage bacteria in vacuum packed cooked ham analyzed by PCR-DGGE

The effectiveness of Lactobacillus sakei B-2 inoculated as a protective culture on the inhibition of spoilage bacteria on sliced vacuum packed cooked ham was investigated by using culture-dependent and -independent approaches. Total microbial DNA was directly extracted from both control and treatment samples, and subjected to a nested PCR protocol, PCR–DGGE analysis was used to identify and monitor the dynamic changes in the microbial population, followed by partial 16S rDNA sequencing. The DGGE profile demonstrated that the protective culture effectively suppressed growth of predominant spoilage bacteria L. sakei, Lactobacillus curvatus and Leuconostoc mesenteroides in cooked ham during storage at 4 °C, however, growth of uncultured Leuconostoc was not inhibited. The shelf-life of this product inoculated with L. sakei B-2, at levels of 5.91 ± 0.04 log₁₀ CFU g⁻¹ was 35 days, compared to 15 days of control samples, when the ham was stored at 4 °C.     

Technological characterization of a bacteriocin-producing Lactobacillus sakei and its use in fermented sausages production

The aim of this paper was the technological characterization of a Lactobacillus sakei strain, able to produce the bacteriocin sakacin P, that was originally isolated from naturally fermented sausages. Experiments were conducted in situ, using MRS-based medium, and in situ, when the strain was inoculated as starter culture in real sausage fermentation. The results obtained underlined that the strain was able to grow in conditions that are commonly used in the production line, and only lactose and high concentrations of NaCl (5% w/v) reduced the capability for bacteriocin production. When inoculated in sausages, the strain showed a good performance, being able to colonize rapidly the ecosystem. A high number of isolates, capable of producing sakacin P, were already isolated after the third day of fermentation, and persisted throughout the course of the fermentation. The inoculated strain also affected other microbial colonization trends; in fact the total bacterial count and fecal enterococci showed a rapid decrease at the end of the fermentation. Moreover, during sensory evaluation, the final sausage product received high scores for the parameters of tenderness and juiciness, with medium acidity and low rancidity. Lastly, the panelists preferred the sausages produced with the L. sakei characterized in this study when compared to a fermented sausage produced with a commercial starter.     

Fermentation of Lye-treated Carrots by Lactobacillus plantarum

Sodium hydroxide treatment of peeled and trimmed carrots was investigated to rid them of natural epiphytic microflora that interferes with fermentation. It also formed a buffered brine by subsequent neutralization with acetic acid. Two lye concentrations (1% and 2% NaOH) and three treatment times (1,15 and 30 min) were evaluated. Inoculation of Lactobacillus pluntarum into NaOH-treated carrot brines resulted in a controlled fermentation yielding lactic acid almost exclusively. Percent carbon recovery varied from 83.7 to 148.3. More than 92% of available glucose and >85% fructose, but <13% sucrose, were utilised after 7 days fermentation. Texture and surface color (L*) of fermented NaOH-treated carrots were affected (p < 0.05) by NaOH concentration and treatment time. The product flavor was not adversely affected by alkaline treatment.     

添加复合发酵剂对发酵猪肉干食品安全性的影响

以清酒乳酸杆菌（Lactobacillus sakei）和木糖葡萄球菌（Staphylococcus xylosus）为复合发酵剂发酵猪肉干,研究复合发酵剂对发酵猪肉干腐败微生物生长增殖、组胺积累、亚硝酸盐残留、脂质氧化及挥发性氨基氮（TVB-N）生成的影响。结果表明:接种复合发酵剂显著（p<0.05）抑制发酵过程中大肠杆菌、李斯特菌、假单胞菌和金黄色葡萄球菌等腐败微生物的生长增殖;发酵结束时,添加复合发酵剂和自然发酵组的组胺含量分别为0.32和8.85 mg/kg,亚硝酸钠残留量分别为8.95和45.6 mg/kg,硫代巴比妥酸（TBA）值分别为0.67和1.54 mg MDA/kg,TVB-N含量分别为1.23和5.25 mg/100 g。添加复合发酵剂组的组织状态、风味和色泽等感官评分均高于自然发酵组,获得了优良的感官特性。      

植物乳杆菌发酵鲜整枣的工艺研究

对植物乳杆菌发酵鲜整枣的工艺进行了探索。即以鲜枣为原料,经植物乳杆菌发酵,使枣内的一部分糖转化成乳酸,提高了枣的保藏性,同时改善了枣的风味,生产出一种新产品。     

鲈鱼肠道LactobacillussakeiLY1-6对荧光假单胞菌抑制作用研究

目的:从海鱼肠道中筛选对荧光假单胞菌具有较强抑制作用的乳酸菌。方法:采用牛津杯琼脂扩散法筛选菌株,通过生理生化反应和16S rRNA测序进行菌株生物学鉴定,利用蛋白酶、p H和温度等因素对抑菌活性进行分析,采用扫描电镜分析乳酸菌无细胞上清液（CFS）对荧光假单胞菌细胞结构的完整性影响。结果:从鲈鱼肠道中筛选出对荧光假单胞菌具有较强抑制活性的菌株LY1-6,经生理生化和16S rRNA测序鉴定为清酒乳杆菌（Lactobacillus sakei）。菌株LY1-6 CFS经胃蛋白酶处理后其抑菌活性完全丧失,经中性蛋白酶、木瓜蛋白酶、胰蛋白酶和碱性蛋白酶处理后其抑菌活性分别丧失了38.22%、38.00%、22.48%和18.46%。在p H2.5⁵.0具有抑菌活性,并具有良好的热稳定性,初步结果表明LY1-6 CFS中抑菌活性物质可能为细菌素。扫描电镜结果表明经LY1-6 CFS处理使荧光假单胞菌细胞结构被破坏并溶解。结论:来自鲈鱼肠道的清酒乳杆菌LY1-6对荧光假单胞菌具有较强抑制作用,其抑菌活性物质为细菌素类,作用机制为破坏细胞的完整性,可作为控制水产品中荧光假单胞菌腐败生物保鲜的出发菌株。      

干酪乳杆菌纯种发酵大豆乳培养基的优化调配

从益生菌乳制品中自行分离选育出的生长繁殖力强、发酵活力高的干酪乳杆菌(05-20)为试验菌株,研究了牛乳和蔗糖在大豆乳中的添加量对干酪乳杆菌在大豆乳中发酵的凝乳时间、凝乳时活菌数、pH值、滴定酸度及产品感官风味的影响,通过方差分析确定了发酵培养基中牛乳和蔗糖的最适添加量分别为20%和7%,完成了以大豆乳作为干酪乳杆菌最佳载体的初步探索,为进一步研制开发益生菌发酵大豆乳制品奠定了基础.     

植物乳杆菌C88发酵特性研究

对一株本实验室筛选的益生菌植物乳杆菌C88的发酵特性进行了研究,以一株商业化益生菌L.rhamnosus GG为参照。结果表明,菌株C88的凝乳活性较弱,蛋白水解活性较高;4℃贮28 d,该菌株表现出良好的存活能力,活菌数高于L.rhamnosus GG。菌株C88对金黄色葡萄球菌的抑制作用较强;丙酸钙对其生长无显著影响;药敏实验表明该菌株对所选10种抗生素均表现出一定的耐药性;本研究对植物乳杆菌C88发酵特性的研究为其进一步应用于益生性发酵乳的研究开发提供实验依据。     

金银花乳杆菌发酵凉茶的研制

该研究的目的在于探究植物乳杆菌发酵金银花凉茶的工艺条件。以金银花为原料,通过单因素试验和正交试验,研究植物乳杆菌PMO接种量、发酵温度、发酵时间和糖添加量对金银花凉茶发酵过程的影响,并对发酵工艺条件进行优化。结果表明,植物乳杆菌PMO经过驯化过程,其在金银花凉茶中具有优良的增殖活性;金银花凉茶中绿原酸含量受发酵过程影响较小,始终稳定在29.20 mg/g左右;金银花凉茶最佳发酵工艺条件为植物乳杆菌PMO接种量3%、发酵温度37 ℃、发酵时间14 h、糖添加量7%。     

乳酸菌在肉制品加工中的应用和研究

本文介绍了乳酸菌的利用现状,着重阐述了乳酸菌在肉制品中的应用研究和工艺操作.     

利用纳豆菌和乳酸菌共同发酵奶液的研究

利用纳豆菌和乳酸菌共同发酵奶液,对发酵过程中发酵乳的外观、口感、酸度、微生物数量以及纳豆激酶酶活力的变化进行了研究。结果表明:接种纳豆菌8h后再接种乳酸菌进行发酵的样品,在外观、口感、乳酸菌以及纳豆激酶酶活力方面都有效好效果。     

副干酪乳杆菌发酵废液的重复利用

以副干酪乳杆菌(Lactobacillus paracasei)R8为研究对象,采用7.5 L及100 L发酵罐对其发酵废液的重复利用进行了初步研究。在7.5L罐上对副干酪乳杆菌发酵废液的可重复利用性进行了验证,并在100 L罐上进行了应用尝试。研究结果表明,副干酪乳杆菌R8的发酵废液可以重复利用1次,在100 L发酵规模下,废液的重复利用可以节约培养基成本8%,节约发酵液用水43%。     

新疆地产干果复合汁乳酸菌发酵饮料的研制

以葡萄干、杏干、酸梅、红枣为原料,利用保加利亚乳杆菌和嗜热链球菌为菌种研制发酵型饮料。采用正交试验,分别确定其最佳发酵液、最佳发酵条件和口感稳定性的工艺配方,用火焰原子吸收法和高效液相法分别测定成品中的微量元素锌、铁及VC。实验结果显示最佳发酵液中杏干、酸梅、红枣、葡萄干与水的浸泡比分别为25%、25%、10%、20%(g/100ml);最佳发酵工艺条件:接种3%,发酵时间36h,发酵温度为40℃,发酵饮料调配最佳配方:在发酵液中加入蔗糖6%,柠檬酸0.04%,CMC-NA0.4%,黄原胶0.03%。微量元素锌、铁和VC含量分别为0.23、0.52、0.344mg/ml。     

自然发酵肉制品中干酪乳杆菌的分离和鉴定

从自然发酵香肠和自制腌肉中分离得到68株乳酸菌,通过对菌株发酵适应性的研究,筛选出2株性能优良,适用于肉制品发酵的乳酸菌C67和R6,初步生化鉴定表明,2株均为干酪乳杆菌。文中还对所获得的菌株的相关发酵性能进行了测试。