Organoleptic characteristics of foods

What are

The organoleptic characteristics of a food reflect the qualities perceivable through one or more sense organs. Appearance, color, shape, aroma, taste, texture and characteristics connected to it (fluidity, viscosity, friability) are just some of the most important and well-known organoleptic characteristics.

The senses most involved in the perception of these characteristics are taste, smell and sight.

Through the " panel tests " the experts evaluate color, shape (sight), consistency (sight, hearing, touch), smell (smell) and taste (smell, taste) of a given food. These tests are performed by people who are prepared and trained to recognize these characteristics, thanks also to the use of special techniques.

The panel tests are also accompanied by chemical and physical tests to objectively assess the safety and any food fraud. These controls are able, for example, to detect the rancidity of a flour even before the alteration can be perceived by human taste.

The association between sensory tests, therefore subjective, and chemical-physical exams, provides useful elements for the production and trade of food products.

Food color

it is a very important organoleptic characteristic from the psychological point of view; there are, for example, advertising marketing studies focused exclusively on the appearance of labels and their ability to attract consumers.

From the chemical and legislative point of view we talk about:

Pigments : substances naturally present in the food that reflect color; lycopene, if we think of tomatoes, is an example of pigment.
Dyes : substances that are fixed on the food and change its natural color.
- Chemically, we classify the coloring substances in:
  - Cromophores: color bearers.
  - Auxocrome: color adjuvants, that is able to exalt it.

Food taste

it can be modified thanks to one or more substances that interfere with the perception of the four main characteristics (or base) of the taste: salty, sweet, sour (or sour) and bitter.

Acid	It depends on the concentration of H + ions in the food
Salty	Alkali metal salts. In table salt or NaCl, the perception of salty is linked to the presence of sodium, while chlorine, by itself, is not salty.
Sweet	Hydroxyl groups (abound in sugar) and / or formation of hydrogen bridges (some amino acids or small peptides are able to give a sweet taste to the food)
Bitter	Mg ++ and NH4 + ions or alkaloids (found in coffee, digestive, and many other foods)

Smell

it depends on the volatility, the liposolubility and the tendency of some substances to form bonds with proteins.

Food aroma

complex sensations linked to the smell, taste and physical structure of the product; in some cases hearing is also involved ("crack" of the breadstick, "scrock" of the chips, etc.).

The aromatic substances that are most perceived, both positive and negative, are almost all liposoluble. For this reason, in most cases, a tasty food is a fatty food (a lean steak is almost tasteless, while a sausage is usually much tastier).

Often the aroma of a food product is enhanced through specific techniques (coffee roasting, milk or cheese fermentation, cured meats etc).