Food Science and Technology Research
Online ISSN : 1881-3984
Print ISSN : 1344-6606
ISSN-L : 1344-6606
Food Technology and Engineering
Original paper
Technical paper
  • Takashi Kuribayashi, Akira Hatakeyama, Jun Yarimizu, Keigo Arimoto, Mi ...
    2022 年 28 巻 3 号 p. 217-224
    発行日: 2022年
    公開日: 2022/05/20
    [早期公開] 公開日: 2022/02/25
    ジャーナル 認証あり HTML

    Sake yeasts synthesize alcohols and other components, such as ethyl caproate, ethyl caprylate, and isoamyl acetate, which impart a unique and refined flavor profile to sake. In this study, a sake yeast mutant, K901C8, with high ethyl caprylate productivity was isolated from Kyokai no. 901 (K901), which has been passaged since 1993 at Yoshinogawa brewery, and its fermentative properties were investigated. This mutant was isolated from 960 antibiotic-resistant mutants obtained from 2.1× 107 cells with cerulenin as an inhibitor of fatty acid synthesis. In small-scale sake brewing experiments, the K901C8 mutant produced a high level of ethyl caprylate, which imparts a pineapple- and apricot-like flavor to sake. In the industrial-scale brewing, K901C8 showed fermentative properties similar to those of the wild-type K901, whereas K901C8 produced more ethyl caprylate than K901. These results demonstrate the potential of using K901C8 for producing high-quality sake with a novel flavor.

Food Science and Chemistry
Original papers
Short Communication
  • Naraporn Phomkaivon, Nia Amilia, Witwasin Tanintaratan, Lina Yonekura, ...
    2022 年 28 巻 3 号 p. 275-283
    発行日: 2022年
    公開日: 2022/05/20
    [早期公開] 公開日: 2022/03/14
    ジャーナル 認証あり HTML

    The antiallergic activity of extracts of Naruto Kintoki sweet potato peel was enhanced after cooking the peel using three conventional methods. Using 400 µg/mL extracts, baking showed the highest suppression of β-hexosaminidase release (36.9%), followed by microwaving (41.9%) and boiling (64.2%). Significant suppression of β-hexosaminidase release from RBL-2H3 cells in response to Naruto Kintoki peel extract was attributed to compounds 9 (r = 0.91, p < 0.01) and 11 (r = 0.76, p < 0.05). UPLC/ESI-Q-TOF-MS analyses of compounds 5 and 8 clarified the existence of two sulfates of flavonol aglycones (3, 5, 3′-trihydroxy-7, 4′-dimethoxyflavone 3-O-sulfate and 3, 5-dihydroxy-7, 4′-dimethoxyflavone 3-O-sulfate). Baking the sweet potato peel changed compounds 5 and 8 to compounds 9 and 11 with enhanced antiallergic activity. Specifically, IC50 values changed from 11.0 µg/mL (5) to 4.1 µg/mL (9) and from 12.1 µg/mL (8) to 4.4 µg/mL (11). We found those four chemicals contributed to the observed antiallergic activity of Naruto Kintoki sweet potato peel extracts.