Effect of Fermentation Temperature on the Quality of Pear Wine

The aroma and quality of pear wine was strongly affected by fermentation temperature by influencing the metabolism of microorganism during the fermentation. In this study, Korla fragrant pear was used as raw material to make pear wine at the fermentation temperature of 8, 13, 18 and 23 ℃. After fermentation, the basic physicochemical indexes, chromaticity and browning degree of pear wine were determined. Headspace solid phase micro-extraction gas chromatography mass spectrometry (HS-SPME-GC-MS) was used to qualitatively and semi-quantitatively study the effect of fermentation temperature on the quality of pear wine. The results showed that the pear wine with lower fermentation temperature ULT (8 ℃) and LT (13 ℃) had lower acidity, lower browning degree and higher brightness, and the wine was more transparent. A total of 28 volatile compounds were identified in pear wine, including 12 kinds of esters, 8 kinds of alcohols, 4 kinds of acids, 1 kind of phenol and 3 kinds of alkanes. The ester content of pear wine produced at 13 ℃ was the highest, which was 3150.30 μg/L, the content of etheyl octanoat, a characteristic aroma substance, was the highest, up to 1939.45 μg/L. At the same time, the sensory score was the highest, 83.7 points, which indicated that 13 ℃ was the appropriate fermentation temperature of pear wine. In conclusion, fermentation at 13 ℃ has the potential to improve the quality of pear wine.