The idea that we can’t taste what we’re eating doesn’t make sense
Juyun Lim
Until now, it was believed that humans could only detect five different primary tastes: sweet, salty, sour, bitter and, added to the list seven years ago, umami. But now researchers claim we’re capable of tasting a “starchy” flavour too.
Juyun Lim, Associate Professor of Food Science and Technology at Oregon State University, conducted the research, which suggests that our palate can detect carbohydrates founds in foods such as pasta, potatoes and bread.
“Every culture has a major source of complex carbohydrate. The idea that we can’t taste what we’re eating doesn’t make sense,” she told New Scientist.
To test the sixth-taste theory, Dr Lim and her team dissolved different levels of carbohydrates in liquid solutions and gave them to 22 participants who were asked to rate how each tasted.
“They called the taste ‘starchy’,” Dr Lim said.
Previously, many scientists believed that humans could only taste the sugar in carbohydrates, as enzymes in our saliva break starch molecules into simple sugars, leaving a sweet taste in our mouths.
But even when volunteers were given a compound to block the saliva enzyme and sweet receptors, they were still able to taste the starch - which suggests humans can pick up on a starchy flavour before it has been broken down into sugar.
“Asians would say it was rice-like, while Caucasians described it as bread-like or pasta-like,” she added.
Sugar tastes great in the short term, but if you’re offered chocolate and bread, you’d choose the bread in larger amounts
Juyun Lim
Dr Lim was unable to find receptors on the tongue which specifically detect starchy flavours, which means it can't currently be declared as a primary taste, but she believes it would be a useful flavour for humans to be able to detect naturally as carbs are a good source of slow-releasing energy.
“I believe that’s why people prefer complex carbs,” she said.
“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.”