发酵肉制品中乳酸菌的分离鉴定技术的研究

对发酵肉制品中乳酸菌的分离、纯化以及鉴定技术进行了研究,结果从发酵香肠、腊肠、火腿中分离筛选得到2株德氏乳杆菌,并建立了一套发酵肉制品中乳酸菌的分离鉴定方法.     

发酵肉制品中乳酸菌分离鉴定技术的研究

对发酵肉制品中乳酸菌的分离、纯化以及鉴定技术进行了研究,结果从发酵香肠、腊肠、火腿中分离筛选得到2株德氏乳杆菌,并建立了一套发酵肉制品中乳酸菌的分离鉴定方法。     

发酵肉制品中乳酸菌的分离、筛选和鉴定

对发酵肉制品中乳酸菌的分离、纯化以及鉴定技术进行了研究,结果从发酵香肠、腊肠、火腿中分离筛选得到2株德氏乳杆菌,并建立了一套发酵肉制品中乳酸菌的分离鉴定方法.     

自然发酵肉制品中乳酸菌的分离及特性研究

以MRS和改良TJA(改良番茄汁琼脂培养基)培养基为基础培养基,从自然发酵肉品中分离得到8个菌株,其中4株为乳酸菌,3株为杆菌,1株为球状菌。进一步测试表明:4株乳酸菌在30℃培养时,生长最好;在pH3.5～4.0时生长良好;4株乳酸菌在10%NaCl的环境中均能生长,其中以2%～6%的NaCl浓度内生长最适宜;属兼性厌氧菌;对大肠杆菌产生一定的抑制作用。分离出的4株乳酸菌均适宜作为发酵肉制品的发酵剂。     

发酵肉制品乳酸菌菌种筛选研究

在菌种筛选试验中,Lp、La在6%NaCl、1.50×-4NaNO2下能够存活,两株菌种均无分解蛋白质和脂肪的性质,且有一定共生性。所以,Lp、La可以作为肉制品发酵剂:而St、LB不能作为制品发酵剂。     

自然发酵肉制品中乳酸菌的筛选

为获得适合肉制品发酵的优良乳酸菌菌株,对来源于自然发酵肉制品中的25株乳酸菌进行筛选,其中19株在6 g/100 mL NaCl和150 mg/kg NaNO_2液体培养基中生长较好,结合其他发酵特性实验,13株乳酸菌符合肉制品发酵剂标准,挑选其中3株进行产酸能力、生长曲线及不同温度条件下生长情况的研究。结果表明:3株菌均具有较强的增殖及产酸能力;培养12 h时菌株即进入稳定生长期,培养24 h时培养基pH值降到4左右;在肉制品的发酵温度范围内能较好地生长。经形态学和16S rRNA序列分析,3株菌均为弯曲乳杆菌,它们均可作为潜在的开发肉制品发酵剂的出发菌株。     

泡菜中优良乳酸菌的分离鉴定及其发酵性能的研究

从多种泡菜中分离出92株菌，对其在低温下发酵能力进行测试，筛选出了四株产酸较快、发酵风味较好的菌株Leu．1、Leu．2、Lact．1和Lact．2。经API系统鉴定，Leu．1和Leu．2为肠膜明串珠菌肠膜亚种(Leuconostoc mesenteroides subsp.mesenteroides)，Lact．1为干酪乳杆菌干酪亚种(Lactobacillus casei subsp.casei)，Lact.2为植物乳杆菌(Lactobacillus plantarum)。在10℃发酵白菜中，接种发酵的产酸速度和风味明显优于自然发酵，其中Leu．1和Leu．2发酵前期产酸较快，发酵11d白菜汁pH值达3．67，而Lact．1和Lact．2发酵11d pH值达3．30左右。另外还对四株菌的相关发酵性能进行了测试。     

发酵肉制品常见乳酸菌的发酵性能研究

选择发酵肉制品中常见的6株乳酸菌,对其发酵性能进行研究,结果表明:6株菌均有较强的耐亚硝酸盐能力,其中植物乳杆菌、干酪乳杆菌、清酒乳杆菌、发酵乳杆菌能够耐受6%食盐,且无蛋白和脂肪分解能力。发酵乳杆菌产酸能力弱,不能有效控制致病菌的生长,不适合单独作为发酵剂使用。清酒乳杆菌、植物乳杆菌和干酪乳杆菌能够有效降低pH值,抑制致病菌的生长,适合发酵肉制品的生产。     

发酵白菜中乳酸菌的分离及鉴定

利用钙溶圈等方法从5种发酵白菜中分离筛选出了13株菌，确认其中9株为乳酸菌，经过形态学测试及生理生化反应试验，最后确定9株菌中有8株属于乳杆菌属，分别是：植物乳杆菌3株、短乳杆菌2株、微小乳杆菌2株、发酵乳杆菌1株。     

泡菜中乳酸菌的分离、鉴定及其发酵性能研究

目的对从自制泡菜中分离出的3株发酵风味和生长较好的乳酸杆菌进行鉴定和生长特性测试.方法用API系统对菌种进行鉴定,测定不同时间、盐度、pH、温度条件下菌种的生长情况及不同发酵过程中亚硝酸盐含量的变化,并通过感官评价测定泡菜的风味.结果Lab-1为短乳杆菌(Lactobacillus brevis),Lab-2为干酪乳杆菌干酪亚种(Lactobacillus casei subsp.casei),Lab-3为植物乳杆菌(Lactobacillus plantarum).对这3株菌株的生长特性的测试结果表明它们的生长温度范围较宽,在最适生长温度32℃,最适生长pH 6.0,NaCl含量小于4.5%的条件下菌株能够正常生长.发酵实验表明,人工接入混合菌种可以有效降低亚硝酸盐含量,并且泡菜的风味接近于自然发酵,其稳定性比自然发酵的好.结论本实验结果可为人工接种泡菜的工业化生产提供依据.     

不同来源产细菌素乳酸菌的分离筛选及鉴定研究

从自制的发酵胡萝卜汁、泡菜汁、黄瓜汁、黄豆汁、绿豆汁,以及市售的蜂蜜、鲜奶、干酪中,通过琼脂扩散法最终筛选出有1株乳酸菌具有良好的抑制大肠杆菌、金黄色葡萄球菌、单核细胞增生李斯特菌、志贺氏菌以及沙门氏菌的作用.以单核细胞增生李斯特菌为指示菌,通过排出有机酸、过氧化氢的干扰因素后,发酵离心液用胰蛋白酶和胃蛋白酶处理后,发酵液的抑菌活性急剧下降,从而确定产生的抑菌物质具有蛋白质性质,是一种细菌素.经过形态学测试及生理生化反应试验,最后确定这株菌为鼠李糖乳杆菌.     

冷藏鲜肉中腐败乳酸菌的分离及鉴定

利用稀释平板法从冷藏3 d的肉样品中共分离出60株疑似乳酸菌菌株,经过2次划线分离,然后进行革兰氏染色、镜栓、过氧化氢酶试验、明胶液化试验、硝酸盐还原试验和H2S检验,得到36株乳酸菌.将分离出的这36株乳酸菌,经过形态学和生理生化鉴定,确定他们属于5大类,即清酒乳杆菌,13株;马里乳杆菌,8株;消化乳杆菌,7株;口乳杆菌,4株;未知乳杆菌,4株.     

泡菜中乳酸菌优良菌株的分离鉴定及发酵性能的研究

从多种酸、泡菜中分离出86株菌,对其在最适温度和低温下产酸速率及硝酸盐降解能力进行测定,筛选出5株产酸速率快,硝酸盐降解能力强的菌株,经形态学鉴定及生理生化反应试验,初步鉴定其为:植物乳杆菌2株,短乳杆菌1株,戊糖乳杆菌1株,肠膜明串珠菌葡聚糖亚种1株.并对5株菌的发酵性能进行测定.     

乳酸菌的固定化方法及其发酵特性的研究

对乳酸菌固定化工艺参数及发酵特性进行了研究,结果表明,乳酸菌包埋法固定最佳工艺条件为:海藻酸钠的浓度为2%,菌体的稀释比例为1:1,CaCl2溶液的浓度为1.5%,菌种的固定化温度为42℃。固定化菌种胶珠含菌量为4.59×109个/g。固定化乳酸菌产酸和耐酸能力强,菌种活力得到保持,具有持久和可重复利用的特点。     

STUDIES ON SOME TECHNOLOGICAL PROPERTIES OF PREDOMINANT LACTIC ACID BACTERIA ISOLATED FROM NIGERIAN FERMENTED FOODS

In a programme to develop starter cultures for improving the safety and quality of traditional fermented foods in Africa, a study was conducted on lactic acid bacterial (LAB) strains isolated from the traditional selected Nigerian fermented foods kunun-zaki, wara, nono, iru. The LAB strains representing the dominating population of each product, were identified as Enterococcus faecalis (1), Pediococcus pentosaceus (4), and Lactobacillus fermentum (19). All the strains grew at 450°C, an observation which could be attributed to the tropical environment of the fermented foods. They produced a moderate spectrum of enzymes of relevance to food processing, and exhibited similar patterns of enzymatic activity between species, but generally showed weak esterase and lipase activities as compared with peptidases. While no proteinase activity was detected, most strains showed high galactosidase activity. Two strains showed ability to degrade phytic acid. None of the strains produced any detectable bacteriocins or biogenic amines under the test conditions used, and all were unable to hydrolyse bile salt. Eleven (45.8%) of the strains coagulated skim milk at 30°C within 24-36 h, and at 37°C within 12-20 h together with a moderate drop in pH. The results are discussed to highlight the relevance of technological features of starter cultures in food processing in the African environment.     

菜谷系列乳酸发酵饮料工艺与发酵配套工业化条件

在菌种筛选的基础上,进一步对菜谷原料的处理工艺、发酵条件、风味口感以及产品质量稳定性等相关配套条件进行深入研究,优化并建立工艺技术成熟、品种花色多样和色、香、味俱佳的菜谷类乳酸发酵系列产品的生产工艺并具备指导产品的工业化生产的条件.     

FUNDAMENTALS AND PERSPECTIVES FOR THE USE OF BACTERIOCINS PRODUCED BY LACTIC ACID BACTERIA IN MEAT PRODUCTS

Bacteriocins of lactic acid bacteria (LAB) are proteinaceous compounds that may present antimicrobial activity towards important foodborne pathogens and spoilage-related microflora. Due to these properties, bacteriocin-producing strains or purified bacteriocins have a great potential of use in biologically based food preservation systems. Despite the growing number of articles describing the isolation of bacteriocinogenic strains, genetic determinants for production, as well as the purification and biochemical characterization of these inhibitory substances, there are only limited reports of successful application of bacteriocins to meats.

This paper presents a critical review of the methods available for screening of bacteriocin-producing LAB strains from meats and also discusses the proposed mechanisms of action for LAB bacteriocins. Additionally, an overview of the Brazilian experience in the application of LAB bacteriocins to meats and meat products is given.     

FUNDAMENTALS AND PERSPECTIVES FOR THE USE OF BACTERIOCINS PRODUCED BY LACTIC ACID BACTERIA IN MEAT PRODUCTS

Bacteriocins of lactic acid bacteria (LAB) are proteinaceous compounds that may present antimicrobial activity towards important foodborne pathogens and spoilage-related microflora. Due to these properties, bacteriocin-producing strains or purified bacteriocins have a great potential of use in biologically based food preservation systems. Despite the growing number of articles describing the isolation of bacteriocinogenic strains, genetic determinants for production, as well as the purification and biochemical characterization of these inhibitory substances, there are only limited reports of successful application of bacteriocins to meats.

This paper presents a critical review of the methods available for screening of bacteriocin-producing LAB strains from meats and also discusses the proposed mechanisms of action for LAB bacteriocins. Additionally, an overview of the Brazilian experience in the application of LAB bacteriocins to meats and meat products is given.     

乳酸发酵型百合乳饮料工艺的研究

研究了以百合酶解液、鲜牛奶为主要原料，生产出一种纯天然保健乳饮料的工艺，并对加工过程中的护色、酶解和稳定剂的选择等进行了探讨，最终确立了产品的最优配方和生产工艺。