黑果枸杞酵素发酵过程中理化成分变化及微生物类型分析

The changes of physicochemical components and the analysis of microbial types during fermentation of Lycium ruthenicum Murr. enzymes

以黑果枸杞、枸杞、蕨麻、玛卡为原料,经自然发酵制作黑果枸杞酵素。通过检测不同发酵阶段中微生物数量、还原糖、蔗糖、可滴定酸、花青素含量的变化,从而比较与分析自然发酵过程中的理化成分变化与微生物数量变化之间的关系,并筛选出适宜黑果枸杞酵素发酵的优势微生物菌株。结果表明:在发酵15~25 d时,微生物数量达到最高水平,总菌数达2.91×10~9 cfu/m L,酵母菌数达1.83×10~9 cfu/mL,乳酸菌数达0.82×10~9 cfu/mL;在40 d发酵过程中,可滴定酸含量由0.62%升高到2.12%。还原糖含量由14.99%降低到7.69%,蔗糖含量由6.10%降低到0.87%;花青素含量由最初的7.39%降低到第55天的3.14%,保留率为42.5%。经形态学与分子生物学鉴定,筛选出1种酵母菌(库德里阿兹威毕赤氏酵母菌Pichia kudriavzevii)、1种曲霉菌(短青霉菌Penicillium brevicompactum)、2种乳酸菌(乳酸片球菌Pediococcus acidilactici、植物乳杆菌Lactobacillus plantarum)。这将为今后黑果枸杞酵素接种发酵提供特定菌种,并能够调控黑果枸杞酵素发酵过程中的理化成分变化及微生物生长规律。

With Lycium ruthenicum Murr.,Lycium barbarum Linn.,Potentilla anserina Linn.and Lepidium meyenii Walp.as raw materials,the Lycium ruthenicum Murr.enzymes were made by natural fermentation.By measuring the changes of microbial quantity,reducing sugar,sucrose,titratable acid and anthocyanin content in different fermentation stages,the relationship between the changes of physicochemical components and the changes of microbial quantity during natural fermentation was compared and analyzed.The dominant microbial strains that suitable for the fermentation of Lycium ruthenicum Murr.enzymes were screened out.The results showed that during 15~25 days of fermentation,the microbial count reached the highest level,with the total bacterial count reaching 2.91×10~9 cfu/mL,the yeast count reaching 1.83×10~9 cfu/mL,and the lactic acid bacteria count reaching 0.82×10~9 cfu/mL.During 40 days of fermentation,the titratable acid content increased from 0.62%to 2.12%,the reducing sugar content decreased from 14.99%to 7.69%,and the sucrose content decreased from 6.10%to 0.87%.The anthocyanin content decreased from the initial 7.39%to 3.14%on the 55 th day,and the retention rate was 42.5%.On the basis of morphological and molecular biological identification,one yeast(Pichia kudriavzevii),one aspergillus(Penicillium brevicompactum),two lactic acid bacteria(Pediococcus acidilactici,Lactobacillus plantarum)were screened out.This will provide specific strains for the inoculation and fermentation of Lycium ruthenicum Murr.enzymes in the future,and can regulate the changes of physicochemical components and microbial growth during the fermentation of Lycium ruthenicum Murr.enzymes.