四川老卤泡菜基本理化指标及特征菌群分离鉴定

The physical and chemical properties of Sichuan old brined Paocai and the isolation of characteristic microbes

以8份四川老卤泡菜样品为研究对象,对其理化指标和风味物质进行测定,发现老卤泡菜的pH值平均为3. 59,总酸含量平均为12. 47 mg/g,总糖含量平均为31. 17 mg/g,NaCl含量平均为4. 46 g/100 g,总氮含量平均为0. 17 g/100 g,渗透压在434～2 238 mOsm/kg。GC-MS分析发现,老卤泡菜的挥发性风味物质主要是烷烃和酯类,包括甲基环戊烷、柠檬烯、乙酸乙酯等;主要的非挥发性风味物质包括乳酸、丙二醇、甘油、琥珀酸、草酸、甘露醇、γ-氨基丁酸和果糖等,其中甘露醇和γ-氨基丁酸是主要的活性物质。从8份老卤泡菜样品分离到36株菌,分别为植物乳杆菌32株、布氏乳杆菌2株和耐乙醇片球菌2株,这3种菌是老卤泡菜的特征菌群,对泡菜发酵具有重要作用。

In this study,eight old brined Paocai samples were collected from Sichuan and their physiochemical properties and flavor substances were investigated.The results showed that the average pH of old brined Paocai was 3.59 and the average acid content was 12.47 mg/g.The average sodium chloride content,total nitrogen content and osmatic pressure were 4.46 g/100g,0.17 g/100g and 1 547 mOsm/kg,respectively.According to the GC-MS analysis,the major volatile flavor substances were alkane and esters,including methyl-cyclopentane,limonene and ethyl acetate.The major non-volatile flavor substances were lactic acid,propylene glycol,glycerol,butanedioic acid,mannitol,γ-aminobutanoic acid and fructose,wherein mannitol andγ-aminobutanoic acid were the main bioactive substances of Pacocai.36 strains were isolated from Paocai and were identified as Lactobacillus plantarum,Lactobacillus buchneri and Pediococcus ethanolidurans,which were the characteristic microbes of old brined Paocai and played important roles in paocai fermentation.