降亚硝酸盐乳酸菌筛选及榨菜汁发酵性能评价

Screening of Nitrite-degrading Lactobacillus Strains and Evaluation of Fermentation Performance in Pickled Mustard

高盐、亚硝酸盐含量超标是榨菜生产中常见的问题。筛选降亚硝酸盐乳酸菌,评价其对发酵榨菜性能的影响,是提高榨菜安全和品质的有效方法之一。通过初步筛选,获得多株具降亚硝酸盐能力的乳酸菌菌株,其中植物乳杆菌ZJ316、LZ227和ZFM228有较强的亚硝酸盐降解能力,降解率高于93%。植物乳杆菌ZJ316在榨菜汁培养基中(含4%NaCl)产酸能力最强,产酸速度最快,培养24 h的发酵液pH值降至4.10,可滴定酸度达0.14%。GC-MS分析表明,植物乳杆菌ZJ316在发酵过程中能产生丰富的醇类和酸类化合物,可赋予榨菜优良的发酵风味。榨菜汁培养基中,植物乳杆菌ZJ316对亚硝酸盐的降解率为95.23%,最适耐受范围0~3.60 mg/mL。植物乳杆菌ZJ316具有较好的应用潜力,可望应用于榨菜食品的生产。

The excessive salt and nitrite content are potential risk issues during pickled mustard production.Screening nitrite-reducing lactic acid bacteria(LAB)and evaluating the effect on the performance of fermented mustard are the effective strategies to improve the safety and quality of mustard.In this study,a serial of LAB strains were screened,of which Lactobacillus plantarum ZJ316,LZ227 and ZFM228 showed the best nitrite degrading ability with a degradation rate over 93%.All the three strains exhibited great acid producing ability in pickled mustard juice medium containing 4%NaCl.Lactobacillus plantarum ZJ316 produced acids faster than the other two strains,by which the pH of fermentation broth decreased to 4.10 and the titratable acidity reached 0.14%.GC-MS analysis found that Lactobacillus plantarum ZJ316 was able to produce alcohol and acid compounds during the fermentation process,which could offer excellent flavors to pickled mustard.The nitrite degrading rate of Lactobacillus plantarum ZJ316 in the pickled mustard juice medium is 95.23%,and the strain was tolerant to nitrite at the concentration of 0 to 3.60 mg/mL.In conclusion,the lactic acid bacterial strain ZJ316 has a potential to be used in food industry to develop fermented pickled mustard with great safety and nutritional values.