Abstract: On the basis of one-factor-at-a-time experiments, Box-Behnken design (BBD) and response surface methodology (RSM) were applied to optimize extraction with 37% HCl and subsequent precipitation with CaCl2 involved in the extraction of L(+)-tartaric acid from Vitis quinquangularis lees. The optimal HCl treatment conditions were 82 ℃ of temperature, 7 min of treatment time and 18% (V/V) of lees-to-HCl. The optimal precipitation conditions were addition of CaCl2 at a ratio of 50 g/L for 2.4 h of precipitation at pH 6.64. Under these conditions, the L(+)-tartaric acid yield from Vitis quinquangularis lees was 41.63 g/L and the actual recovery rate of L(+)-tartaric acid was 87.64%.

Key words: Vitis quinquangularis, lees, L(+)-tartaric acid, response surface methodology, extraction