Volatile Compounds of Raw Spirits from Different Distilling Stages of Luzhou-flavor Spirit

Abstract

Distillation process is closely correlated with the quality and yield of the raw spirit. The volatile properties of raw spirits from three distilling stages (head, heart and tail) of Luzhou-flavor spirit were investigated based on GC and GC-MS analyses. A total of 71 compounds were identified and ester derivatives attributed the largest number and concentration of volatile compounds in three raw spirits. The total concentration of raw spirit was decreased from the head raw spirit (5105 mg/L) to the tail raw spirit (1843 mg/L). Many volatile compounds with high concentrations such as acetaldehyde, 1-hexanol, 2-methylbutanoic acid, hexanoic acid, and ethyl hexanoate were found to decrease during distillation. Odor active value (OAV) was used to evaluate the contribution of special compounds to the whole odor of the raw spirit. Ethyl hexanoate followed by ethyl butyrate, ethyl heptanoate, ethyl octanoate, and 3-methylbutanal were found to be the most potent odor-active compounds. The liquid-liquid extraction together with GC-MS and GC analyses could be a useful tool to characterize the volatile composition of different distilling cuts of Chinese spirit. The decreasing of total content of volatile compound was determined by the ester derivate because of its high volatility and content.