The foods that make up the upper-level protein group, poultry, milk, eggs, cheese and yoghurt are rich in a wide variety of minerals. The consumption of these foods and the quantity of these foods should be in accordance with the age group and physical activity of the individual.

The eggs we usually consume are hen's eggs (Gallus gallus). The European Union regulates the marketing of these eggs with rules on production, marketing, labelling and hygiene.

Egg production systems. Depending on the type of farm, eggs for consumption are called:

Eggs from caged hens.

Eggs from free-range hens.

Organic eggs produced.

Egg products. The term egg product refers to new ways of presenting, preserving and marketing eggs out of their shells, ready for consumption. It is a product consisting mainly of all or part of the egg contents.

Milk is an exceptionally rich food. There are different ways of presentation and treatment for its preservation:

Liquid milks:

• Raw milk.
• Fresh pasteurised milk.
• Sterilised milk.
• UHT. (Ultra-high temperature sterilisation)

Concentrated milk.

Evaporated milk

Condensed milk

Powdered milk.

Yoghurt is a fermented milk obtained by mixing two dairy bacteria, streptococcus thermofilus and lactobacillus bulgaricus.  At the end of fermentation (45°C for 2 hours), the coagulated milk turns into yoghurt.

Natural yoghurt: No additives. Depending on the amount of fat, they are: whole, semi-skimmed, skimmed or enriched with cream.

Sweetened plain yoghurt: With added sugar.

Sweetened yoghurt: with the addition of authorised sweeteners.

Yoghurt with fruit or juice.

Flavoured yoghurt: with flavourings to give different flavours.

In addition to these types of yoghurt, we can find other varieties on the market, such as Greek yoghurt, in which the liquid whey is extracted from the milk, resulting in a thicker product, with less sugar and more protein. Kefir is a dairy product similar to liquid yoghurt, fermented through the action of a group of yeasts and bacteria also called grains or nodules.

There are countless varieties of cheese, whether made from cow's, sheep's or goat's milk, cheese is made using rennet, enzymes that coagulate and thicken the milk. This rennet can be of animal origin (obtained from the stomach of lactating ruminants), vegetable origin (obtained from fig or thistle sap), microbial or synthetic. The water is removed from the milk, so the cheese is a concentrate of proteins, vitamins, mineral salts and easily digestible fat. For all these reasons, cheese is full of benefits for our organism and the WHO (World Health Organization) recommends its consumption.

Poultry refers to domesticated birds used in food, for consumption of its meat. The term typically includes members of the orders Galliformes, such as chickens and turkeys, and Anseriformes, waterfowl such as ducks and geese. However, this is not a strict classification, and the term can also refer to other types of birds that are used in cooking, such as pigeons and even ostriches. For birds such as pheasant, quail and wild ducks, the term "game birds" is commonly used.