Meat can be divided into animal meat and poultry meat. The former includes pork, beef, mutton and rabbit, while the latter includes chicken, duck and goose. Meat food is rich in fat, protein, minerals and vitamins, while carbohydrate is less than plant food and contains no plant fiber. The change of meat composition depends not only on the relative quantity of fat meat and lean meat, but also on the difference of animal species, age, fattening degree and parts taken. Common eggs are eggs, duck eggs and goose eggs. And the nutritional components of all kinds of eggs are roughly the same. The protein content in egg white is 1 1% ~ 13%, and the moisture content is 85% ~ 89%. Egg yolk contains only 50% water, and most of the rest is protein and fat, with a ratio of 1: 2. In addition, eggs also contain carbohydrates, minerals, vitamins, pigments and so on. Aquatic products include all kinds of fish, shrimp, crab, shellfish and seaweed (kelp, seaweed), among which fish is the most. The nutritional composition of fish varies with the species, age, size, fatness, fishing season, producing area and sampling position of fish. Generally speaking, protein is the main component of fish solids. Low fat content, but more unsaturated fatty acids; Fish also contains vitamins, minerals and other ingredients, especially marine saltwater fish contains a certain amount of iodized salt and potassium salt. It is of great significance to human health. Milk is a kind of food with rich nutrition, easy digestion and absorption and high edible value. It contains not only protein and fat, but also lactose, vitamins and inorganic salts. Generally, fresh milk contains 87% ~ 89% moisture, 3% ~ 4% protein, 3% ~ 5% fat, 4% ~ 5% lactose, 0.6% ~ 0.78% minerals and a small amount of vitamins. Milk is the most commonly eaten milk by human beings. Compared with human milk, milk contains more protein, but less lactose. Therefore, when milk is used instead of breast milk, it should be properly blended to make its chemical composition close to breast milk.