乳杆菌发酵速煮薏米的工艺优化

Optimization of Quick Cooking Technology of Coix Seed Fermented by Lactobacillus

采用食淀粉乳杆菌CGMCC1.3395发酵制备速煮薏米。通过单因素和正交试验对发酵时间、含水量、接种量和发酵温度等发酵条件进行优化,以确定最佳工艺,并以原料薏米(CK1)和常规浸泡薏米(CK2)为对照,比较发酵前后薏米蒸煮食味及营养品质变化。结果表明:食淀粉乳杆菌CGMCC1.3395发酵速煮薏米的最佳工艺参数为发酵时间12 h、发酵温度30℃、含水量40%、接种量0.5%。在此条件下,发酵后薏米的最佳蒸煮时间为48.0 min,较CK1、CK2分别降低45.9%和22.2%;吸水率和体积膨胀率为分别为278.9%和351.4%,约为双对照的2倍;精米硬度和米饭硬度分别为1079 g和77 g,较双对照均显著降低2倍或以上;米汤p H值为5.50,无明显酸味;米饭食味综合评分显著高于双对照。此外,发酵薏米的总淀粉、总蛋白、粗脂肪含量及γ-氨基丁酸等组分含量分别为57.4%、15.5%、5.39%、903.2 mg/kg,均在发酵后显著增加。综上,该工艺使薏米蒸煮时间缩短、质地变软、口感和营养提升,可为薏米的蒸煮品质改良提供技术参考。

Quick cooking coix seed was prepared by fermentation with Lactobacillus amylovorus CGMCC1.3395.Optimization of fermentation conditions such as fermentation time,moisture content,inoculation amount,and fermentation temperature was carried out through single factor and orthogonal experiments to determine the optimal process.The changes in cooking taste and nutritional quality of coix seed before and after fermentation were compared using raw material coix seed(CK1)and conventional soaking coix seed(CK2)as controls.The results showed that the optimal conditions for fermentation of quick cooking coix seed by Lactobacillus amylovorus CGMCC1.3395 were fermentation time of 12 hours,fermentation temperature of 30℃,water content of 40%,and an inoculation amount of 0.5%.Under these conditions,the optimal cooking time for fermented coix seed was 48.0 minutes,representing a 45.9%and 22.2%reduction compared to CK1 and CK2,respectively.The water absorption rate and volume expansion rate of the fermented coix seed were 278.9%and 351.4%,nearly double those of both control.The hardness of the milled coix seed and cooked coix seed was 1079 g and 77 g,respectively,which was less than half of that observed in CK1 and CK2.The pH of the cooked coix seed soup was 5.50,exhibiting no prominent sour taste.The overall rating of the cooked coix seed was significantly higher than the control.Additionally,the content of total starch,total protein,crude fat andγ-aminobutyric acid were 57.4%,15.5%,5.39%and 903.2 mg/kg,which were obviously increased after fermentation.In summary,this technology can soften texture,reduce cooking time and improve taste and nutrition of coix seed,thus provide a technical reference for enhancing the culinary quality of coix seed.