Exploring the influence of vacuum distillation on volatile profile and sensory characteristics of Rice-flavor baijiu

This study assessed the effects of vacuum distillation (0.2, 0.4, 0.6, 0.8 atm) versus atmospheric distillation on <i>Rice-flavor Baijiu</i>. Distillation time was maximally reduced by 33.78 % at 0.6 atm without reducing yield. Fifty-four VOCs were identified, nineteen and thirteen with OAVs >1 in high alcohol (<b>HAR</b>) and low-alcohol (<b>LAR</b>) raw <i>Baijiu</i> samples, respectively. Branched-chain alcohols exhibited negative pressure correlation, whereas aromatic alcohols showed positive correlation. Short-chain esters fluctuated in <b>HAR</b> but correlated positively in <b>LAR</b>, while long-chain esters exhibited the reverse pattern. Integrated analysis of total acid/ester content, and total OAVs of desirable and undesirable compounds identified 0.6 and 0.8 atm as the optimal pressure. <b>HAR</b> and <b>LAR</b> fractions distilled at 0.6 and 0.8 atm exhibited <i>floral</i>, <i>fruity</i>, and <i>sweet</i> via ester correlations, while 0.2 and 0.4 atm fractions developed <i>solvent</i> from branched-chain alcohols. The results elucidate volatile behavior characteristics under varying vacuum conditions, guiding optimization in <i>Rice-flavor Baijiu</i> production.