自然发酵“老面”与纯种发酵的糙米发糕挥发性成分及品质分析

Analysis of Volatile Constituents and Quality of Brown Rice Cake by Natural Fermentation‘Old Mouth’and Pure Breed Fermentation

以自然发酵“老面”和纯种酵母菌复配植物乳杆菌、酵母菌复配复合乳酸菌为发酵剂制作糙米发糕。利用气相色谱-质谱联用法(GC-MS)结合电子鼻及感官评定分析其挥发性风味成分,结果表明:2%酵母菌复配1.2%植物乳杆菌、2%酵母菌复配0.9%乳酸菌发酵3 h,16%“老面”发酵15 h,3种糙米发糕挥发性风味物质相近。挥发性风味物质主成分分析和聚类分析结果表明:感官评价结果与乙酸丙酯、3-羟基-2-戊酮、乙偶姻、辛酸乙酯、壬醛含量呈正相关。挥发性物质种类主成分分析表明:感官评价结果与酮类、酯类呈显著正相关。同时对其质构特性进行对比分析,结果表明:2%酵母菌复配1.2%植物乳杆菌或0.9%乳酸菌发酵3 h,16%“老面”发酵15 h糙米发糕质构特性最佳。

Natural fermented′old mouth′and pure yeast mixed with Lactobacillus plantarum and yeast mixed with lactic acid bacteria were used as starter cultures to make brown rice cake.The volatile flavor components of brown rice cake were analyzed by gas chromatography-mass spectrometry(GC-MS)combined with electronic nose and sensory evaluation.The results showed that:2% yeast compounded with 1.2% Lactobacillus plantarum,2% yeast compounded with 0.9% lactic acid bacteria fermented for 3 h,16%‘old mouth’fermented for 15 h,the volatile flavor substances of the three brown rice cakes were similar.The results of principal component analysis and cluster analysis of volatile flavor substances showed that the sensory evaluation results were positively correlated with the contents of propyl acetate,3-hydroxy-2-pentanone,acetoin,ethyl octanoate and nonal.The principal component analysis of volatile substances showed that the sensory evaluation results were positively correlated with ketones and esters.At the same time,the comparative analysis of the texture characteristics of brown rice cake showed that 2% yeast combined with 1.2% Lactobacillus plantarum or 0.9% Lactobacillus fermented for 3 h and 16%‘old mouth’fermented for 15 h had the best texture characteristics.