High levels of branched chain fatty acids in nātto and other Asian fermented foods

• Published in: Food chemistry 2019-07, Vol.286, p.428-433
• Main Authors: Wang, Dong Hao, Yang, Yupeng, Wang, Zhen, Lawrence, Peter, Worobo, Randy W., Brenna, J. Thomas
• Format: Article
• Language: English
• Subjects: Branched chain fatty acids; Fatty acid ethyl ester; Fermented food; Fish sauce; Nātto; Shrimp paste
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2019.02.018

•Nātto has 1%,w/w branched chain fatty acids (BCFA) or 0.21–1.43 mg BCFA/g of nātto.•Nātto is the first reported fermented food similar in BCFA to milkfat (0.6–0.7 mg/g)•Fermentation can dramatically increase BCFA content of foods.•Fermented foods provide significant BCFA in human diets low in ruminant products. The mean intake (500 mg/day) of branched chain fatty acids (BCFA) in western countries is from dairy products and beef. We hypothesized that Asian countries with low dairy consumption have an alternative source of BCFA and report the characterization of nātto and selected fermented foods for BCFA content. Nātto BCFA averaged 0.6 (range 0.21–1.43) mg BCFA per g natto (wet weight) and was highly variable. Nātto major BCFA are C14-17 iso- and anteiso-BCFA similar to fluid milk. BCFA concentrations were 1.00 ± 0.64%, 1.63 ± 0.72% and 0.65 ± 0.07%, of total fatty acids in nātto, shrimp paste and fish sauce, respectively. In contrast, saturates, monounsaturates, and major polyunsaturates were more constant (coefficient of variation = 21%, 26% and 4% compared to 64% for nātto BCFA). Detection of fatty acid ethyl esters were confirmed in miso and found in homemade kimchi. Habitual nātto and/or fermented seafood consumption could support BCFA intakes similar to dairy consumption.