'Starchy' now joins the other five tastes on our palettes, sweet, sour, salty, bitter, and umami
While we might think of the overwhelming desire to sink our teeth into a fresh white blah or seasoned steamed spuds dripped with hot melted butter as a uniquely Irish interest, now scientists believe that our craving for carbs might actually represent as sixth taste. Joining the ranks of sweet, salty, sour, bitter, and umami – a Japanese loan-word that translates as ‘pleasant savoury taste’ – starchy has reportedly also earned its place on the palette.
Juyun Lim, Associate Professor of Food Science & Technology at Oregon State University, is the scientist behind the pioneering research, which suggests that human being can detect carbohydrates founds in foods like bread, pasta, and potatoes.
“Every culture has a major source of complex carbohydrate. The idea that we can’t taste what we’re eating doesn’t make sense,” Dr Lim told New Scientist.
To examine the sixth-taste theory, Dr Lim and her research team took complex carbohydrates and dissolved them into varying levels in liquid solutions. Then the samples were given to 22 volunteers to consume and rate on taste.
Before this test, most scientists in the area of taste believed that human beings were only capable of recognising the taste of sugar in carbohydrates; enzymes secreted in our saliva work to break down starch molecules into simple sugars, which is why bread and pastas, when chewed, can become slightly sweet tasting in our mouths.
But in this test, the volunteers were given a compound to block their salivary glands from releasing the enzyme. It also acted to block sweet receptors. Despite this, the test subjects were still able to taste the starch, leading to the scientists concluding that human beings can identify starchy labours before they are broken down into sugar.
“Asians would say it was rice-like, while Caucasians described it as bread-like or pasta-like,” Dr Lim said.
When publishing her findings, Dr Lim has said that she is, as yet, unable to find the specific taste receptors on the tongue that are specifically capable of detecting starch, which means ‘starchy’ cannot be scientifically declared a primary taste. But evolutionarily speaking, the reason why humans are most likely able to naturally detect the flavour is to make us better at finding foods that are good at the slow-release of energy.
“I believe that’s why people prefer complex carbs,” Dr Lim 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.”