植物乳杆菌和棒状乳杆菌对发酵萝卜干风味品质的影响

Effects of Lactobacillus plantarum and Lactobacillus rodarum on Flavor Qualityof Fermented Dried Radish

以白萝卜为原料,经初步脱水制成半干萝卜干,分别接种植物乳杆菌L1和棒状乳杆菌L3以及混合菌种发酵萝卜干。以自然腌制发酵为对照,测定萝卜干发酵过程中的pH值和总酸的变化,并对发酵后萝卜干的质构、色差、氨基酸成分和挥发性风味物质进行分析,探讨2种乳酸菌对萝卜干发酵风味品质的影响。结果表明,接种乳酸菌发酵能加快pH值的下降和总酸的上升。混菌发酵的萝卜干总酸和游离氨基酸含量最高,分别达到0.729 g/100 g和16.01 mg/g。接种棒状乳杆菌L3的萝卜干色泽与未发酵萝卜干最为接近。接种植物乳杆菌L1的萝卜干质地、口感都最好。从4组萝卜干中共检测出挥发性风味成分61种,混菌发酵的风味物质种类虽不是最多但风味评价最好,某些特有的香气较突出。综合品质指标数据和感官评价结果,最后选用混合菌种作为发酵剂,所得产品的色泽、质地和风味俱佳,品质高于自然发酵和单一菌种发酵的萝卜干。

In this paper,semi-dried radish was prepared from white radish byprimary dehydration,then the pure fermentation or mixed fermentation of dried radish was conducted inoculated with the Lactobacillus plantarum L1 and Lactobacillus rodarum L3,respectively.In contrast to spontaneous pickling and fermentation,the effects of two kinds of lactic acid bacteria(LAB)on the fermentation of dried radish were investigated by determine the pH and total acid values.The texture,color difference,amino acid composition and volatile flavor of dried radish were also detected after fermentation.The results showed that the fermentation of LAB accelerated the decrease of pH and the increase of total acid.The content of total acid and free amino acid in dried radish fermented by mixed fermentation was the highest,they reached 0.729 g/100 g and 16.01 mg/g respectively.The color of dried radish fermented by Lactobacillus rodarum L3 was the closest to unfermented dried radish.The dried radish fermented by Lactobacillus plantarum L1 has the best texture.A total of 61 volatile flavor compounds were detected in 4 groups.The type of the flavor substances by mixed fermentation is not the most,but the flavor is harmonious and some particular aroma is the more abundant.Based on the comparison of data and sensory evaluation,complex strains as a starter was an ideal selection because the quality of dried radish was higher than that of natural fermentation and single strain fermentation.