Effect of rice cultivars on the fermentation characteristics and aroma profile of distilled soju using N9 yeast

This study aimed to investigate the fermentation performance and quality characteristics of distilled soju produced from various rice cultivars using Saccharomyces cerevisiae N9 yeast. The rice cultivars included high-yield varieties such as Samkwang (SK, control), Shindongjin (SDJ), Baromi2 (BRM2), Guemgang-1 (GG-1), Hanareum-4 (HAR-4), Chohong (CH), Saemimyeon (SMM), Mirchal (MRC), Irumi (IRM), and Migam (MG). The fermentation results showed that the high-amylose SMM exhibited significantly lower CO2 production and alcohol content (16.57%), indicating its unsuitability for distilled soju production. The pH, total acid, and amino acid content were similar among the rice cultivars. However, volatile acid content was comparatively higher in the SDJ and SMM cultivars. Organic acid composition revealed that succinic acid, citric acid, and lactic acid were the predominant components contributing to ester compound formation. Distilled soju made from the SDJ, IRM, and MG cultivars exhibited higher organic acid levels, enhancing ester production. Sensory evaluation indicated that distilled soju made from SDJ, with the highest ethyl acetate concentration, scored the highest in aroma and overall preference. This result is likely due to the positive contribution of ester aroma compounds to the sensory profile. In contrast, SMM was found to be unsuitable for distilled soju production. The SDJ cultivar showed superior fermentation efficiency, higher volatile aroma compound formation, and greater consumer preference, making it suitable for producing distilled soju.