A novel chemical sensor utilizing surface plasmon resonance for quality control of Japanese sake

A chemical sensor based on surface plasmon resonance (SPR) with four channels is studied for the quality control of the fermentation process of Japanese sake. Each channel of the SPR sensor responds to a change in quality of the moromi (fermented for 5, 14 and 23 days), which is sake in the final stage of fermentation. The responses of each channel of the SPR sensor clearly change with the number of fermentation days, indicating that an SPR sensor with four channels is useful for quality control of the production of Japanese sake. The SPR sensor, in which distilled water is used as the reference liquid, also responds to different kinds of Japanese sake. This result strongly suggests that the SPR sensor is useful for the identification of the type of Japanese sake.