Even when they make us fat and miserable, we still love our carbs and have a very difficult time giving up on them. While it’s true that low carb diets are on the rise, most health-oriented individuals still choose to replace ‘bad’ carbs with healthier alternatives instead of completely tossing them away. What is it about carbs that make them so irresistible for the human sensory system?
First of all, carbohydrates and sugars are responsible for a large part of a product’s flavor, aroma and texture, most often making it more delicious and appealing. And since carbohydrates are the main energy source of the human diet, all cultures in the world have a major source of carbs on their daily menu. Furthermore, carb-loaded foods affect the workings of our brains, most notably enhancing the release of ‘happy’ chemicals, which is the reason behind their fascinating ability to soothe emotional pain. More often than not, this results with overindulging in high-carb foods and some experts believe this to be the root of the current global obesity epidemic.
But most recently, a team of researchers at the Oregon State University discovered another reason why carbs are such an important part of our lives – turns out, we all have a carb-based primary taste.
The taste buds on our tongue are onion-shaped groupings of taste cells that interact with the chemicals from the food we eat after it has been dissolved by the saliva. These interactions cause electrical changes in the taste cells which then send signals to the brain. It’s long been thought that humans are only able to register five primary tastes on their tongue – salty, sweet, sour, bitter and umami. But this new study, published in the journal Chemical Senses, suggests that there is a starchy, sixth taste that helps us register the flavor of rich sources of complex carbs. Up until now, food scientists believed that we detect the presence of starch when our enzyme-filled saliva breaks it down into simple sugars, which we then register as sweet tastes. The authors of the new study decided to test this idea by giving volunteers a variety of mixed carbohydrate solutions and asking them to taste them and describe their flavor. And a big number of participants were able to describe the flavor of the solutions as “starchy” and associate it with the primary source of carbs represented in their culture – Asians explained the taste as rice-like, while those with European ancestry said it tasted like bread.
The researchers then increased the challenge by creating a follow-up experiment in which they were given a compound that neutralized their sweet taste receptors. After a round of tasting, most of them were still able to register the starchy taste they described after the first experiment. Finally, they were given a compound that inhibits the enzyme that breaks down the long-chain starch polymers into short-chain ones, and after tasting both solutions that contain long-chain polymers and solutions that contain short-chain polymers, it was shown that they were able to register a starchy flavor only in the latter, which further supports the proposed theory of the sixth starchy taste. As we already know, starch is a complex carbohydrate in the form of many small molecules that are attached to each other in large chains, which get broken down into smaller ones once they are digested for the purpose of meeting the energy needs of all cells in our bodies.
The authors explain that their findings make a lot of sense from an evolutionary stance. Since starch and other complex carbohydrates are tremendously nutritious and filling, they have always been vital for our survival and our ability to taste them has undoubtedly aided our survival in the same way that taste has helped us detect toxic substances that we need to avoid. In fact, the very reason why taste exists is to enable us to make the difference between foods that are nourishing and provide energy and foods that could harm our health if ingested. And this conclusion could perhaps give us the last piece of the puzzle about the irresistibility of high-carb foods.
What do you think about this discovery? How does your personal relationship with carbs look like? Feel free to share your opinions in the comment section below!