As the food ingredients and food processing steps affect both the nutrient content of foods and sensory properties, such as flavour and texture these are intertwined.

Taste is primarily thought to be a nutrient-sensing system: sweet signals the presence of energy/carbohydrates in foods, salt intensity represents sodium concentrations, umami may be related to the protein content of food, and sour and bitter relate to the PH and the concentration of potentially toxic substances.^[1] However, the relationship between ingredients and taste is not always as clear as it seems.

Sweetness shows an association with carbohydrate content (r=0.33-0.57), but this association is not very strong. In the case of sweetness, it may be that a food product is very sweet, but it does not contain any sugar (sucrose) as it is sweetened using other sweeteners, such as stevia, aspartame, or another non-sugar sweetener.

Saltiness shows a high association with NaCl content (r=0.52-0.77). In the case of salt (NaCl), the perceived salty taste also depends on the other ingredients present. For example, if other more dominant tasting ingredients are present such as sugar, salt is not always perceived.

food Complexity

Food items can be a complex composition of tastants and structure. The most simple food is water with a single tastant, such as a solution of water with sucrose.

Adding an additional tastant to food can make it more complex, as tastes can either have a suppressing or synergistic effect. Sweet and salt tastes can for example suppress bitter. This is why adding sugar can make the bitter taste of coffee more acceptable. Milk is also used to make coffee more acceptable; the fat layering effect of milk in on the tongue can suppress the binding of caffeine to the bitter receptors, giving a lower bitter signal to the brain.

food structure

Food structure also plays a part in taste perception. Since tastants need to be dissolved in saliva before being able to bind to a taste receptor, tastants in liquid food matrices are easier perceived compared to tastants in solid matrices. Also tastants in warm foods are perceived more intense compared to cold foods. Think about the different perception of sugar in warm and cold apple sauce.

However, the rate at which the food is consumed is also affecting the perceived intensity and exposure. A soda can be consumed relatively quickly (even without tasting) while a candy stays in the mouth for much longer before it can be swallowed safely.