Umami is one of the five basic tastes (along with sweetness, sourness, bitterness, and saltiness). It’s often described as being “savoury” or “mouth-watering”. The taste is activated by glutamate taste receptors in the mouth. Glutamate is found in foods such as tomatoes, cheeses, meats, and fermented foods. It can also be added to food in the form of monosodium glutamate (MSG).
A dictionary of culinary terms