Abstract: In this study, the composition of volatile flavor substances during the fermentation of cream was analyzed by solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). A total of 32 volatile substances were identified at five different periods, among which acids were the most abundant. Principal component analysis (PCA) revealed that the composition of volatile compounds differed at different fermentation periods, and samples from different periods could be clearly distinguished. Nine key flavor components, including capric acid, caprylic acid, δ-decalactone, 2-nonanone and 3-hydroxy-2-butanone, were identified by calculating odor activity values (OAVs). Five sensory attributes of the samples were scored by descriptive sensory analysis. The correlations between key flavor substances and sensory attributes were analyzed by partial least squares regression (PLSR) analysis, and it was found that the fermented and creamy flavor had strong correlations with capric acid, capric acid, δ-decalactone, 2-decanone, 2-nonanone and 3-hydroxy-2-butanone. This study is of great significance to regulating the production of fermented cream.

Key words: cream; fermentation; volatile substances; descriptive sensory analysis; partial least squares regression analysis