山西地方自然发酵蔬菜发酵过程中细菌多样性分析

为探究山西地方自然发酵蔬菜发酵过程中细菌菌群结构,采用Illumina HiSeq对不同发酵时期的发酵蔬菜样品中细菌进行测序,且对地方自然发酵蔬菜制作过程中细菌总数及乳酸菌数、基本理化指标进行检测与分析。结果表明,地方自然发酵蔬菜的发酵前期细菌多样性丰富,随着发酵时间的延长细菌种群结构趋于稳定,发酵中后期样品主要菌属为乳杆菌属(Lactobacillus);pH值随发酵时间延长呈下降趋势,总酸反之,成品发酵蔬菜中细菌总数和乳酸菌数分别为1.2×10~7 CFU/g和2.5×10~6 CFU/g,亚硝酸盐含量为0.15 mg/kg,pH值为3.22,总酸含量为1.98 g/kg,乳酸菌数与亚硝酸盐呈彼消此长趋势。本研究揭示了山西地方发酵蔬菜中细菌群落结构及差异,为地方自然发酵蔬菜的商业化生产提供理论依据。

Analysis of Bacterial Diversity during Fermentation of Naturally Fermented Vegetables in Shanxi

Changes in the bacterial community structure during the fermentation of naturally fermented vegetables in Shanxi were studied by Illumina HiSeq sequencing. Bacterial DNAs were extracted from samples collected at different fermentation stages and were sequenced. These samples were analyzed for their aerobic plate counts, lactic acid bacterial counts, and physicochemical indicators. The results showed that the bacterial diversity of the fermented vegetables was rich in the early stage of fermentation. The bacterial community structure became stable with the prolongation of fermentation time. The main genus in both the middle and late fermentation stages was Lactobacillus. During the fermentation period, pH increased and total acid content decreased. The aerobic plate count and lactic acid bacterial count in the finished fermented vegetables were 1.2 × 107 and 2.5 × 106 CFU/g, respectively. The nitrite content was 0.15 mg/kg, the pH was 3.22, and the total acid content was 1.98 g/kg. The number of Lactobacillus and nitrite showed an opposite trend. This study will hopefully provide a theoretical basis for the commercial production of fermented vegetables.