Abstract: To better understand the changes in color, taste, aroma, and quality of pine pollen vinegar during fermentation, several evaluation indexes were used, including active ingredients, antioxidant capacity, color difference, electronic tongue analysis, free amino acids, organic acids, volatile compounds, and sensory scores.Principal component analysis, partial least squares discriminant analysis, and odor activity values were employed for further variance analysis.The results indicate that the contents of total phenols, total flavonoids, vitamin C, free amino acids, and organic acids in the pine pollen juice significantly increase during the fermentation process. The electronic tongue analysis showed that the fermented samples had reduced bitterness and increased freshness.Through gas chromatography-mass spectrometry (GC-MS) analysis, a total of 110 volatile compounds were detected during the fermentation process. Aldehydes, acids, and esters were identified as the main aroma substances of pine pollen vinegar.Ethanol, 2-ethylhexanol, phenylethanol, isobutyric acid, ethyl acetate, nonanal, anisole, and acetic acid were identified as the key differentiating substances in the fermentation process, conferring a pleasant aroma to the pine pollen vinegar.Furthermore, sensory evaluations showed that pine pollen vinegar was superior to pine pollen juice in terms of color, flavor, aroma, and overall acceptability.These findings lay a theoretical foundation for the production of high-quality pine pollen vinegar and promote the deep processing and utilization of pine pollen.

Key words: Pine pollen, fermentation, Vinegar, HS-SPME-GC-MS, Volatile compound, Bioactive substance