关键词: 辅助发酵菌株；发酵乳；品质

Abstract: The purpose of this investigation was to study the influence of adjuvant starter cultures on the quality of fermented milk. Seven strains of common lactic acid bacteria, including Lactococcus lactis subsp. cremoris (Lcr), Lactococcus lactis subsp. lactis (Ll), Lactobacillus casei (Lca), Lactobacillus fermentum (Lf), Lactobacillus rhamnosus (Lr), and two Lactobacillus plantarum strains (Lp1 and Lp2), were used separately as adjuvants to a commercial starter culture for fermented milk. The results showed that addition of adjuvant starter cultures could shorten the fermentation time and affect the pH value of fermented milk during storage. Moreover, Lcr and Ll could cause significant changes in the oxidationreduction potential during fermentation. Rheological measurements indicated that these strains could increase the viscosity, and reduce the elasticity and fluidity of fermented milk. The texture analysis showed that all the strains could increase the water-holding capacity, and Lr, Lf and Lp1 could enhance the cohesiveness and adhesiveness of fermented milk. Gas chromatography-mass spectrometry (GC-MS) analysis and principal component analysis showed that Lr, Lp1, Lp2 had little effect on the flavor of fermented milk, while Lca could promote the formation of heptanol, benzaldehyde and 2-tridecanone, and Lf, Ll and Lcr could increase the content of flavor substances such as short-chain and medium-chain fatty acids in fermented milk.

Key words: adjuvant starter culture; fermented milk; quality