Discrimination of saltiness with coexisting components using multichannel taste sensor with lipid membranes

Saltiness elicited by salt is one of the basic tastes. However, components of salt on the market differ depending on manufacturing processes and its t aste as well. Salt manufactured by ion-exchange membrane process is compose d of more than 99% pure sodium chloride, while bay salt contains trace coex isting components. Despite reports on sensory evaluation, the differences i n taste are still uncertain because of a small amount of coexisting compone nts. We studied the taste of salt with trace coexisting components; the bit tern ("nigari" in Japanese) was evaluated objectively and quantitatively us ing a multichannel taste sensor with lipid/polymer membranes. A taste senso r is comprised of several types of lipid/polymer membranes for transforming information of taste substances into electric signals. The model samples w ere composed of sodium chloride and trace coexisting components such as mag nesium sulfate, magnesium chloride, calcium chloride and sodium chloride. T he taste sensor clearly discriminated each sample according to the response patterns. Based on the sensor outputs, we evaluated the taste by means of the combination of principal component analysis and ionic strength. The res ults show the taste of salt with nigari has a correlation with ionic streng th.