为研究乳酸菌发酵对石斛汁中功能活性物质及风味成分的影响。以铁皮石斛汁为原料，采用嗜酸乳杆菌（Lactobacillus acidophilus，La）与副干酪乳杆菌（Lactobacillus paracasei，Lp）混合液态发酵，分析石斛汁中多糖、乙酸乙酯萃取成分、挥发性成分、游离氨基酸及有机酸的变化。结果表明，铁皮石斛汁发酵后，多糖平均分子量由184.40 ku减小至91.27 ku，多糖含量极显著降低21.91%（P<0.01）；试验鉴定发酵前后乙酸乙酯萃取成分分别为20种和16种，相同成分11种，差异成分14种；挥发性成分由发酵前的21种增至发酵后的26种，发酵后酚类与醇类物质相对含量增多，花香香气物质相对含量增多；发酵后检测出15种游离氨基酸，游离氨基酸种类较发酵前增加6种，赋予发酵汁甜味和鲜味，除天冬氨酸外，其他种类游离氨基酸含量均极显著升高（P<0.01）；发酵前后分别含有3种和4种有机酸，乳酸仅在发酵后检出，其含量占比有机酸总含量的76.11%，赋予发酵汁柔润的口感。由此可见，La与Lp混合发酵可使铁皮石斛汁中产生丰富的活性物质与风味成分。

To investigate the effect of lactic acid bacteria fermentation on the functional active substances and flavor components in Dendrobium juices, Dendrobium officinale juice was used as the raw material, and the changes of its polysaccharides, ethyl acetate-extracted components, volatile components, free amino acids and organic acids induced by liquid fermentation with the mixture of Lactobacillus acidophilus (La) and Lactobacillus paracasei (Lp) were analyzed. The results showed that after the fermentation of Dendrobium officinale juice, the average molecular weight of polysaccharide decreased from 184.40 ku to 91.27 ku, and the polysaccharide content significantly decreased (by 21.91%; P<0.01); 20 and 16 ethyl acetate extracted components were identified before and after the fermentation, respectively, with 11 being identical components and 14 being different components; the number of volatile components increased from 21 (before fermentation) to 26 (after fermentation). After fermentation, the relative contents of phenolic compounds, alcohol substances and floral aroma species increased, increased; After fermentation, 15 free amino acids were detected, among which 6 were not detected before fermentation, giving the fermented juices sweetness and umami taste. Except for aspartic acid, the contents of the other free amino acid species increased highly significantly (P<0.01) after fermentation; There were 3 and 4 organic acids before and after fermentation, respectively. Lactic acid was only detected after fermentation, and its content accounted for 76.11% of the total organic acid content, giving the fermented juices a soft and moist sensation. Thus, the mixed fermentation with La and Lp resulted in the production of rich active substances and flavor components in Dendrobium officinale juices.

江西省重大科技研发专项（20203ABC28W019）