优良乳酸菌的筛选及对腌制茭白品质的影响

Screening of Lactic Acid Bacteria and Its Effect on the Quality of Cooked-pickling Zizania aquatica L.

为获得最适腌制茭白启动发酵剂,缩短腌制茭白生产周期、提高质量品质,从分离筛选保藏的4种乳酸菌菌株(植物乳杆菌、短乳杆菌、嗜柠檬酸明串球菌和戊糖片球菌)中优选出植物乳杆菌和戊糖片球菌2种优良乳酸菌,采用5种不同配比方式分别接种发酵,研究茭白腌制过程中p H、酸度、亚硝酸盐和微生物指标的变化,并对成品的色泽、质地和挥发性风味物质进行分析。结果表明,配比方式对茭白腌制过程中p H、酸度、乳酸菌数和细菌总数的影响不大;在不同配比方式接种中,接种1%植物乳杆菌和2%戊糖片球菌复合菌作为茭白腌制发酵剂,其腌制茭白的"亚硝峰"值最小,为1.62 mg·kg-1,色泽与鲜茭白最为接近,质地口感最好;不同配比方式接种茭白腌制共检测出挥发性风味物质118种,1%植物乳杆菌和2%戊糖片球菌腌制的茭白成品所含风味物质种类和相对含量均较高。因此,最终确定的最佳发酵剂为1%植物乳杆菌和2%戊糖片球菌。本研究结果为茭白的腌制及干制加工的工业化生产提供了理论依据。

For obtaining the starter culture contributes to reduce the fermentation time and improve the quality of pickled Zizania aquatica L, two kinds of lactic acid bacteria （LAB） L. plantarum and P. pentosaceus were selected from L. plantarum, L. brevis, L. citreum, and P. pentosaceus stored, pH, total acidity, nitrite concentration and microbial populations were investigated by inoculated fermentation of Zizania aquatica L. with 5 different kinds of preception, meanwhile, the color, texture and volatile flavor compounds of final product were analyzed. The results indicated that ,i. the parameters of pH, acidity and bacteria counts among different samples had little variation, during the pickling process. In different proportion of inoculation, using 1% Lp and 2% Pp as starter cultures, got the lowest hitrite peak value at reached 1.62 mg·kg^- 1. The color and texture of pickled products were significantly changed. The color was the most close to fresh. And the texture was the most consistent with consumer demand. A total of 118 kinds of volatile compounds were found in different ways of vaccination. Flavor types and relative content reached the highest value using 1% Lp and 2% Pp as starter cultures. The results of this study can provide a theoretical basis for the industrial production of salted and dried of Zizania aquatica L.