关键词: 青稞酒, 多菌种发酵, 化学成分

Abstract: The changes in chemical components of highland barley wine during fermentation with multi-strain starter were studied and compared with those of traditional fermented highland barley wine. The results showed that the dynamic change patterns of chemical components during fermentation with multi-strain starter and traditional starter were similar. pH value decreased rapidly at first and then kept stable at pH 4.0－4.3, the measured total acidity showed an increasing trend. Fermentation temperature increased first and then dropped gradually with the highest value of about 36.2 ℃. Saccharifying enzyme activity and reducing sugar content increased significantly during 0－24 h, and then decreased till the end of fermentation. Total sugar content kept decreasing throughout the whole process. The alcohol concentration fermented by multi-strain starter was 10.30% which indicated a significant (P ＜ 0.05) increase by 57.73% compared with that obtained using traditional starter. Both ammonia-N content and acid proteinase activity increased in the early stages of fermentation followed by a slow decrease. Total free amino acid (FAA) in the final product fermented by multi-strain starter was 80.923 mg/100 mL and no methionine was detected in it. Sensory evaluation showed that the optimal fermentation duration was 60－72 h for highland barley wine production by multi-strain starter. Under this condition, the product was acceptable and maintained the major flavor of wine fermented by traditional starter as evaluated by sensory evaluation.

Key words: highland barley wine, fermentation with multi-strain starter, chemical composition