Revealing the differences in volatile flavor compounds between traditional and modern industrial soy sauce from China and Japan through GC × GC-TOF–MS, chemometrics and sensory analysis

Soy sauce, being a conventional condiment known for its rich flavor, has the ability to enhance the flavor of food and satisfy people's pursuits for a more enjoyable culinary experience. Consequently, it is extensively utilized in Asian cuisine. A comprehensive strategy was employed in this study, which involved multivariate statistical analysis, sensory analysis and chemical analysis of soy sauce from three production processes. Sensory analysis revealed that three types of sauce were significantly different in floral, fruity and nutty/baked aromas. Through GC × GC-TOF–MS analysis, a total of 358 potential aroma compounds were identified, among which 35 compounds were identified as markers for distinguishing the three types of soy sauce. Pyrazines were abundant in Chinese traditional-type soy sauce, while esters were predominant in Japanese soy sauce. The potential relationship between aroma compounds and aroma characteristics of soy sauce produced through three different processes was investigated. This study provides theoretical insights aimed at enhancing the quality of brewed soy sauce.