Metabolomic Insight into Soy Sauce through ¹H NMR Spectroscopy

Abstract

Soy sauce, a well-known seasoning in Asia and throughout the world, consists of many metabolites that are produced during fermentation or aging and that have various health benefits. However, their comprehensive assessment has been limited due to targeted or instrumentally specific analysis. This paper presents for the first time a metabolic characterization of soy sauce, especially that aged up to 12 years, to obtain a global understanding of the metabolic variations through (1)H NMR spectroscopy coupled with multivariate pattern recognition techniques. Elevated amino acids and organic acids and the consumption of carbohydrate were associated with continuous involvement of microflora in aging for 12 years. In particular, continuous increases in the levels of betaine were found during aging for up to 12 years, demonstrating that microbial- or enzyme-related metabolites were also coupled with osmotolerant or halophilic bacteria present during aging. This work provides global insights into soy sauce through a (1)H NMR-based metabolomic approach that enhances the current understanding of the holistic metabolome and allows assessment of soy sauce quality.

Evolution of metabolomics profile of crab paste during fermentation

“…After maximum growth of microorganism, however, new amino acids are probably biosynthesized again or formed from active proteolysis. Such a fluctuation in the levels of amino acids has been reported for other fermented food such as soy sauce (Ko et al, 2009) and wine (Son et al, 2009). Furthermore, a steady loss of taurine in crab paste is likely caused by salting since a similar behavior has been reported for the processed seafood (Dragnes, Larsen, Ernstsen, Mhre, & Elvevoll, 2009;Gormley, Neumann, Fagan, & Brunton, 2007;Piras et al, 2014).…”

“…Since nuclear magnetic resonance (NMR)-based metabolomics analysis is capable of simultaneously detecting all 1 H containing metabolites with concentrations above tens of micro-molar level, it has been widely and successfully applied in understanding the changes of metabolic profiles of fermented food such as Cheonggukjang (Choi, Yoon, Kim, & Kwon, 2007), soy sauce (Ko, Ahn, van den Berg, Lee, & Hong, 2009), and set-yoghurt (Settachaimongkon et al, 2014). This technique is also powerful for evaluating the quality of fish such as gilt-head bream (Sparus aurata) (Picone et al, 2011), mullet roes (Piras, Scano, Locci, Sanna, & Marincola, 2014), and Atlantic salmon fillets (Shumilina, Ciampa, Capozzi, Rustad, & Dikiy, 2015).…”

Metabolite Profiling of Cheonggukjang, a Fermented Soybean Paste, Inoculated with Various Bacillus Strains during Fermentation

“…As nitrogen sources, Val, Leu, and Lys are known to affect the growth of microorganisms, as well as the production of -amylase. 19,20) Levels of Leu and Val were higher in the Cheonggukjang samples fermented with Bacillus licheniformis 58 and Bacillus l. 67 than in the sample fermented with Bacillus amyloliquefaciens CH86-1 at the final stage of fermentation. However, Lys slightly decreased from the beginning of fermentation.…”

“…20,23) The content of Aba in the Cheonggukjang increased constantly fermentation time, but there were no significant differences in Aba content among the Cheonggukjang samples inoculated with the microbial strains. Pyr was observed after 12 h of fermentation.…”

Metabolomic Assessment of Fermentative Capability of Soybean Starter Treated with High Pressure

“…In particular, soybean paste (doenjang) and soy sauce (ganjang) are representative products of soybean fermentation manufactured with meju molded with cooked and crushed soybeans and used as a fermentation starter (2). In general, traditional Korean meju is produced with only soybeans and fermented with various beneficial microflora, typically Bacillus subtilis and Aspergillus oryzae, from naturally inoculated rice straw (3). However, at least 1 year is required for producing high quality soybean products with meju starter (3).…”