Effect of koji fermentation on generation of volatile compounds in soy sauce production

Abstract

Summary The generation of aroma compounds and the changes in sensory characteristics through the soy sauce koji fermentation were investigated to evaluate the crucial impact of the koji fermentation on soy sauce aroma. The sensory analysis showed a marked increase in ‘musty’ and ‘soy sauce‐like’ odours, whereas the beany attribute decreased significantly during koji fermentation. Aldehydes and alcohols were the major volatile classes present in the koji samples. Gas chromatography–olfactometry was used to identify the aroma‐active compounds in harvested koji, and the results showed that 1‐octen‐3‐ol, 3‐octanol, (E)‐2‐octenal, di‐epi‐α‐cedrene, benzeneacetaldehyde and 3‐(methylthio)‐propanal exhibited the greatest aroma intensities in harvest koji. Moreover, relative contents of (E)‐2‐octenal, benzeneacetaldehyde, 3‐(methylthio)‐propanal and 2‐phenylpropenal were found to be positively related to ‘musty’ and ‘soy sauce‐like’ odours. Results from principal component analysis showed that the growth and sporulation of Aspergillus oryzae had the important impacts on the volatile evolution.

Effects of indigenous yeasts on physicochemical and microbial properties of Korean soy sauce prepared by low-salt fermentation

“…These compounds arise from the aromatic amino acid phenylalanine and three branched-chain amino acids and can then be converted into their corresponding alcohols (2-methylbutanol, 3-methylbutanol, and 2-methylpropanol) and/or acids (2-methylbutanoic acid, 3-methylbutanoic acid, and 2-methylpropanoic acid) (Ard€ o, 2006). Compounds generated from lipid oxidation such as octanal and certain ketones are the major contributors to mushrooms and molds (Feng et al, 2013). In the present study, these compounds were slightly different among the three salt conditions.…”

“…As a traditional seasoning, soy sauce is an important part of diets in Asian countries due to its intense savory taste and accompanying characteristic aroma (Yanfang and Wenyi, 2009;Feng et al, 2013). Korean traditional soy sauce is manufactured through high salt brine fermentation using meju (a fermented soybean block) without any other starters (Lee et al, 2006a;Kim and Lee, 2008).…”

Profiles of free fatty acids, free amino acids, and volatile compounds of milk bases fermented byLactobacillus caseiGBHM-21 with different fat levels

“…Separation was performed using a TR-Wax column (30 m × 0.32 mm × 0.25 μm; J&W Scientific, Folsom, CA, USA). The GC-MS conditions used were consistent with those described by Feng et al (2013). Briefly, helium was used as the carrier gas with a flow rate of 1.0 mL·min −1 and a split ratio of 10:1.…”

Formation and reduction of furan in a soy sauce model system

“…In Asian countries such as Korea, China, Japan, Indonesia, and Thailand, many foods involve the Maillard reaction (Feng et al, 2013;Kim & Lee, 2008;Zhang & Tao, 2009). In particular, kanjang (Korean soy sauce) is one of the traditional Korean foods in which furan is made via the Maillard reaction.…”