Abstract: This study systematically investigated the difference in flavor between commercial western sour cream and Inner Mongolian sour cream by the combined use of physicochemical analysis, sensory evaluation, gas chromatography-mass spectrometry (GC-MS), gas chromatography-ion mobility spectrometry (GC-IMS), and electronic nose. The results demonstrated that Inner Mongolian sour cream exhibited significantly higher acidity, fat content, and total volatile compound content than western sour cream (P < 0.05). Sensory evaluation revealed that western sour cream possessed a stronger milky aroma and higher overall acceptability. Volatile compound analysis indicated that the major flavor substances in Inner Mongolian sour cream were acids, alcohols, and esters, whereas those in western sour cream were acids and ketones. Nine key differential flavor compounds were identified based on odor activity values (OAV > 1) combined with variable importance in projection (VIP) values. Partial least squares regression demonstrated that ketones were significantly positively correlated with milky aroma and overall acceptability (P < 0.05), serving as the core flavor compounds contributing to the characteristic milky aroma and consumer preference of western sour cream. In contrast, the high concentration of acids in Inner Mongolian sour cream was associated with undesirable sensory attributes. This research provides theoretical and technical references for the flavor improvement, product development, and quality enhancement of Inner Mongolian sour cream.

Key words: sour cream; Inner Mongolian sour cream; flavor; sensory evaluation; differential analysis