Quality Characteristics and Physiological Activities of Takju with Whole Chestnut

Abstract

This study investigated the quality characteristics and physiological activities of takju prepared with whole chestnut (15%, 30% and 50% with steamed rice) during fermentation. The pH level began to decrease after the secondary brewing stage. The total acid as well as the organic acid content increased during fermentation. Lactic acid and succinic acid were the main organic acids in takju fermented with whole chestnut. The level of total sugar and reducing sugars in takju fermented with whole chestnut increased at the first brewing stage and then slowly decreased after 4 days of fermentation. Also, the total number of viable cells and microbial populations such as lactic acid bacteria and yeast in the treatments increased to about 108 CFU/mL after 1 days of fermentation and then decreased gradually afterward. The ethanol content in takju fermented with whole chestnut rapidly increased during the initial 4 days of fermentation, to a maximum content of 18.2% after 8 days. The colour values of the treatments did not show any significant differences between 0% and 15% chestnut content. However L value decreased, while the a and b values increased when the whole chestnut content above 30%. The total polyphenol level, electron donating ability, nitrite-scavenging ability and ferrous ion effect also increased as the ratio of whole chestnut increased. Sensory scores of takju fermented with 15% chestnut were greater than those of takju prepared by other treatments.

Changes in Flavor- and Aroma-Related Fermentation Metabolites and Antioxidant Activity of Glutinous Rice Wine Supplemented with Chinese Chestnut (Castanea mollissima Blume)

“…Since raw ingredients may retain their biological activity throughout the rice wine fermentation process, a growing list of nutrient-rich raw materials have been explored for their ability to add value to rice wine [14]. Among these materials, chestnut has emerged as an ideal additive to Chinese rice wine fermentation because of its high starch content, which ensures a final ethanol content comparable with traditional rice wines, and because it contains protein levels that are sufficient to support microbial growth during fermentation [15][16][17]. Although the process technology [16,17] and specific yeast strains effective for Chinese chestnut wine fermentation have been studied [13], the effects of chestnut on rice wine flavor profile and nutrient content remain unknown.…”

“…Among these materials, chestnut has emerged as an ideal additive to Chinese rice wine fermentation because of its high starch content, which ensures a final ethanol content comparable with traditional rice wines, and because it contains protein levels that are sufficient to support microbial growth during fermentation [15][16][17]. Although the process technology [16,17] and specific yeast strains effective for Chinese chestnut wine fermentation have been studied [13], the effects of chestnut on rice wine flavor profile and nutrient content remain unknown. In light of its potential increasing usage, it therefore is important to identify the flavor compounds and nutrients found in BLMJ but not in TGRW.…”