Treats and Tricks: The Magic World of Sweetness
Taste is one of the five senses, together with sight, hearing, smell and touch. Food contains small particles, molecules, that entering our mouth are captured by receptors, which tell the brain that their taste is sweet, bitter, sour, salty or umami (the taste of stock cubes). Sweet is the taste people prefer by far. There are thousands of different substances that taste sweet, not only sugar but many other chemical compounds, including a few sweet proteins. Nobody would ever expect sugar to taste like meat or fish, nor a protein to taste like sugar. When the receptor “eats” the sweet molecule, it changes shape and sends a signal inside the cell. Sweet proteins can be almost as big as the receptor, so they cannot enter the cavities of the receptor but they can hug the receptor, stabilizing its active form.