The sweetness of sugar comes from a chemical interaction between sugar molecules and sweet taste receptor cells, which are found in our taste buds and on the roof of our mouth.
Sugar molecules are festooned with oxygen-hydrogen pairs called hydroxyl groups, and these lock into the receptors using an electrostatic attraction known as ‘hydrogen bonding’. As soon as this happens, a chain of molecular events sends nerve signals to the brain, which interprets these signals and gives us the perception of sweetness.
Dr Emma Davies is a science writer and editor with a PhD in food chemistry from the University of Leeds. She writes about all aspects of chemistry, from food and the environment to toxicology and regulatory science.