Analyzing the relationship between the inorganic element profile of sake dilution water and dimethyl trisulfide formation using multi-element profiling

Dimethyl trisulfide (DMTS) is the main component of hineka , an off-flavor generated in sake during storage. Genshu , or undiluted sake, is usually diluted with water during warimizu , the process of adjusting the alcohol content of sake. In this study, we evaluated how the inorganic element composition of sake dilution water affects the DMTS-producing potential of the sake (DMTS-pp, determined as the DMTS concentration in sake stored at 70°C for 1 week after dilution) using inductively coupled plasma–mass spectrometry (ICP–MS). Partial least squares (PLS) regression analysis was conducted with the ICP–MS data as the explanatory variable and DMTS-pp as the response variable, and the selection of inorganic elements for the construction of the PLS model was performed using variable importance in projection scores. The findings confirmed that some of the compounds containing the inorganic elements extracted from the PLS regression analysis contribute to DMTS-pp.