不同乳酸菌荔枝汁发酵特性及其贮藏稳定性的研究

Study on fermentation characteristics and storage stability of litchi juice with different lactic acid bacteria

目的为荔枝乳酸菌发酵饮料的研发筛选优良菌株。方法比较9种乳酸菌在荔枝汁中发酵48 h的活菌数、 pH值和酸度,并观察发酵液在4℃储存条件下这些指标的变化。结果植物乳杆菌FJAT-13737(LactobacillusplantarumFJAT-13737)和德氏乳杆菌FJAT-43773(Lactobacillusdelbrueckii FJAT-43773)发酵荔枝汁48 h的活菌数最高,达109 CFU·mL-1,但在0~7 d储存期内降至108 CFU·mL-1。嗜热链球菌FJAT-43774 (Streptococcus thermophilus FJAT-43774)、嗜酸乳杆菌FJAT-13772(Lactobacillus acidophilus FJAT-13772)和发酵乳杆菌FJAT-13771(LactobacillusfermentumFJAT-13771)发酵液中的活菌数较低,至储存28 d时,活菌数在107 CFU·mL-1,显著低于其他乳酸菌活菌数(P<0.05)。不同菌株荔枝汁发酵液在储存期的最终pH值在3.74~3.93之间,差异不显著(P>0.05)。短乳杆菌FJAT-43776(Lactobacillus brevis FJAT-43776)的荔枝汁发酵液的酸度最高,为140.9°T。在储存期内,不同菌株发酵的荔枝汁的酸度均呈上升趋势,最终酸度在245.8~165.4°T之间。结论为新型荔枝乳酸菌发酵饮料的研发奠定实践基础。

Objective To screen strains for the development of litchi lactic acid bacteria fermented beverage. Methods Litchi juice was fermented with 9 strains for 48 h, then the fermented juice was determined for the parameters such as the number of lactic acid bacteria, pH value and acidity. The 3 parameters were also detected during the storage of the fermented litchi juice at 4 ℃. Results The number of bacteria in litchi juice fermented by Lactobacillus plantarum FJAT-13737 and Lactobacillus delbrueckii FJAT-43773 for 48 h was the highest, which reached 109 CFU?mL-1, but decreased to 108 CFU?mL-1 within 0-7 d of storage. The bacteria number in fermentation of Streptococcus thermophilus FJAT-43774, Lactobacillus acidophilus FJAT-13772 and Lactobacillus fermentation FJAT-13771 was lower than that of other lactic acid bacteria (P<0.05), which reached 107 CFU?mL-1 at 28 d of storage. The final pH value of fermentation of the 9 tested strains was between 3.74 and 3.93 during storage, with no significant difference (P>0.05). Lactobacillus brevis FJAT-43776 showed the highest acidity of litchi juice fermentation (140.9 oT). During storage, the acidity of litchi juice fermented by different strains showed an upward trend, and the final acidity was between 245.8 oT and 165.4 oT. Conclusion This study lay a practical foundation for the development of a new type of fermented litchi Lactobacillus beverage.