酱香型白酒酒糟中生香酵母的筛选及鉴定

Screening and identification of aroma-producing yeast in distiller's grains of Moutai-flavor Baijiu

从酱香型白酒酒糟中通过液态发酵初筛获得7株高产乙酸乙酯的菌株,将其进行固态发酵,其发酵产物经气相色谱(GC)检测共得到64种挥发性化合物,通过主成分分析表明,菌株Y3、Y19和Y22的发酵产物相似。其中,菌株Y3和Y19的乙酸乙酯产量显著高于其他菌株(P<0.05),其次是菌株Y22,但与对照组相比,菌株Y19的吡嗪产量显著减少(P<0.05),菌株Y22的高级醇产量显著增加(P<0.05),均不利于酱香型白酒的生香呈味。故最终选用菌株Y3为生香酵母,通过菌种鉴定,确定该菌株为毕赤酵母(Pichia kudriavzevii)。

Seven aroma-producing yeasts with high yield ethyl acetate were isolated from Moutai-flavor Baijiu through primary screening by liquidstate fermentation. Total 64 flavor compounds were detected by GC from products of solid-state fermentation. Then according to principal component analysis （PCA）, results showed that strain Y3, Y19 and Y22 produced similar flavor compounds. The ethyl acetate yield of strain Y3 and Y19 was significantly higher than others, then followed by strain Y22 （P〈 0.05）. But compared to the control, the pyrazine yield of strain Y 19 reduced signifi- cantly （P〈 0.05） and the higher alcohols yield of strain Y22 increased significantly （P〈0.05）, which went against the flavoring of Moutai-flavor Baijiu. So strain Y3 was screened as aroma-producing strain and identified as Pichia kuclriavzevii.