Long-standing research has suggested the human tongue register five primary tastes - sweet, sour, salty, bitter and Umami, which was added to the list in 2007, but now scientists at Oregon State University believe ‘starchy’ should be added to the list.
Juyun Lim of Oregon State University, told the New Scientist: “Every culture has a major source of complex carbohydrate. The idea that we can’t taste what we’re eating doesn’t make sense.
The idea that carbohydrates can be specifically tasted has previously been rejected by food scientists because enzymes in salvia break the starch down into shorter chains and simple sugars, and it was believed that starch was detected by tasting the sweet molecules.
However, Lim’s team tested the ‘sixth-taste’ theory by dissolving different levels of carbohydrates in liquid solutions and giving them to volunteers, many of whom described the taste as ‘starchy’.
Specific receptors on the tongue to detect starchy flavours were unable to be found, which means it cannot be classed as a primary taste.
Lim added: “We are moving away from the idea of five primary tastes. Sugar tastes great in the short term, but if you’re offered chocolate and bread, you might eat a small amount of the chocolate, but you’d choose the bread in larger amounts, or as a daily staple.”