Wednesday, March 3, 2010
Calcium and taste perception
Calcium may not come to mind when you think of tasty foods, but in a study appearing in the January 8 issue of JBC, Japanese scientists have provided the first demonstration that calcium channels on the tongue are the targets of compounds that can enhance taste.
In addition to molecules that directly trigger specific taste buds (salty, sweet etc.), there are other substances which have no flavor of their own but can enhance the flavors they are paired with (known as kokumi taste in Japanese cuisine).
Exploiting this enhancement could have practical uses in food modulation; for example, creating healthy foods that contain minimal sugar or salt but still elicit strong taste. At the moment, though, the mode of action for these substances is poorly understood.
However, Yuzuru Eto and his colleagues examined whether calcium channels which sense and regulate the levels of calcium in the body might be the mechanism involved; they noted that calcium channels are closely correlation to the receptors that sense sweet and umami (savory) tastes and that glutathione (a common kokumi taste element) is known to interact with calcium channels.
To test their possibility, they created several small molecules that resembled glutathione and analyzed how well these compounds activated calcium channels in cell samples. Next, they diluted the same test substances in flavored water (salt water, sugar water, etc.) and asked volunteers (all trained in discriminating tastes) to rate how strong the flavors were.........