1. The eggs laid by native chickens are relatively small, but because native chickens eat more green leafy vegetables and the content of carotenoids and vitamin B2 in egg yolk is high, the egg yolk is larger and darker. Foreign chickens grow up on feed, and the yolk is smaller and lighter.

2. Because a certain amount of dietary fiber is added to the feed eaten by foreign chickens, the cholesterol and fat content in egg yolk is much lower than that of native eggs, which is more suitable for the elderly. However, native chickens lay fewer eggs and have a long nutrient accumulation cycle, so the eggs laid are high in fat and not suitable for the elderly to eat for a long time.

Choice of eggs

At first glance: the fresh eggshell is rough and covered with a layer of frost powder, and its color is bright and clean; Old eggs have smooth shells; This rotten egg has a black shell with oil stains on it.

Listen 2: Hold the egg firmly with your fingers and gently shake it in your ear to make it sound solid; Shelled eggs and rotten eggs have a "tile" sound; Empty eggs have a hollow sound; The egg cracked.

Three photos: holding the egg in both hands like a tube and looking through it in the sun or light. Good eggs are red, translucent, and the outline of yolk is clear.

Four turns: put the egg on a flat surface and turn it gently with your fingers. When the fresh egg turns, there is resistance in the eggshell, and it will stop after two or three weeks. The bad guys turn long and fast. If the eggs turn neither fast nor slow, it proves that they are not fresh enough.

Five bleaching: put the eggs into 15% salt water, and the fresh eggs sink to the bottom; Old eggs with big heads up and small heads down, half heavy and half floating; Rotten eggs float on the water.

Six views: after the egg is opened, the yolk is round, and if it is spread out, it will not be fresh; The thicker protein is, the fresher it is.