以内蒙古天然风干发酵羊腿为试验对象,基于生理生化、革兰氏染色、16SrDNA测序等筛选鉴定技术,获得符合肉制品发酵剂筛选标准、高耐盐耐亚硝酸盐及较高生长活力的微生物发酵剂菌株,进而探究对发酵猪肉香肠营养品质及安全性的影响.结果表明:经乳酸菌培养基(de Man rogosa sharpe,MRS)、甘露醇氯化钠琼脂培养基(Manitol salt agar,MSA)分离纯化获得的255、142株经初筛后,获得19株乳酸菌、10株葡萄球菌;复筛后,得到具有良好产酸、耐食盐、耐亚硝酸盐特性的乳酸菌(YT-1)、葡萄球菌(YT-2)各一株;经革兰氏染色后形态观察、生理生化、16S rDNA序列分析后确定YT-1、YT-2分别为植物乳杆菌和肉葡萄球菌,2株菌株符合肉制品发酵剂筛选标准要求,且生长活性较高.以植物乳杆菌/肉葡萄球菌(1∶1)为发酵剂发酵猪肉香肠,其显著提高了猪肉香肠中鲜味氨基酸含量、增加了必需脂肪酸比例并降低组胺、酪胺及尸胺等有害胺类的含量.综上表明,YT-1、YT-2是制备发酵肉制品潜在的优良发酵剂.
Screening and Identification of Excellent Fermentation Strains and Their Effects on Nutritional Quality and Safety of Fermented Pork Sausage
The natural air-dried fermented leg of sheep in Inner Mongolia was taken as the test object to isolate and obtain microbial starter strains that meet the screening standards for meat starters,exhibit high salt and nitrite tolerance,and demonstrate high growth activity using physiological and biochemical screening techniques,Gram staining,16S rDNA sequencing,and other screening methods.Then the influence on nutritional quality and safety of fermented pork sausage was explored.The results demonstrated 255 and 142 strains were isolated and purified using lactic acid bacteria medium(de Man rogosa sharpe,MRS)and manitol salt agar(MSA),resulting in the acquisition of 19 lactic acid bacteria strains and 10 Staphylococcus strains.Following re-screening,one strain each of Lactobacillus(YT-1)and Staphylococcus(YT-2)were obtained,both demonstrating good acid production as well as salt and nitrite resistance.Morphological observation,physiological and biochemical analysis,and 16S rDNA sequence analysis after Gram staining confirmed YT-1 as Lactobacillus plantarum and YT-2 as Staphylococcus carnosus.These two strains satisfy the screening criteria for meat product starter culture and exhibit high growth activity.Using Lactobacillus plantarum/Staphylococcus carnosus(1∶1)as starter culture to ferment pork sausage,it significantly increased the content of free amino acids,increased the proportion of essential fatty acids and decreased the content of histamine,tyramine and cadaverine in pork sausage.In conclusion,YT-1 and YT-2 represent potential excellent starters for the preparation of fermented meat products.
万方数据
维普
