A tiny egg holds great nutrition. A thin eggshell, like a protective umbrella, locks the nutrition inside and keeps bacteria out. However, this very fact makes selecting eggs a challenge. To this end, we have invited Xu Guiyun, Deputy Director of the Poultry Quality Supervision, Inspection and Testing Center of the Ministry of Agriculture, to teach everyone how to select fresh, high-quality eggs using the "one look, two shakes, three shines" method.
One Look: Observe the eggshell's color, cleanliness, and whether there are any cracks. "A fresh egg has a complete, non-glossy shell with a layer of white powder on the surface, and it feels rough to the touch," says Xu Guiyun. Eggshells come in many colors—some are more pink, some more yellow, and some more green—but their nutritional value is about the same. Some people believe that pink-shelled eggs are the best, but this is not necessarily true. Free-range eggs have pink shells, but not all pink-shelled eggs are free-range. The depth of the eggshell color is related to the laying cycle; it is typically darkest at the beginning of the cycle and gradually becomes lighter. The depth of the color can also be changed through selective breeding; for example, breeding white-shelled and brown-shelled chickens results in pink-shelled eggs, which have no difference in nutritional value from other eggs. Therefore, there is no basis for calling pink-shelled eggs "free-range eggs." In addition, examine the surface of the egg carefully. If it appears dull, has feces on it, or has cracks, do not buy it. Also, avoid eggs with uneven color or many pockmarks on the surface.
Two Shakes: When buying eggs, hold an egg between your thumb, index finger, and middle finger and shake it. An egg that makes no sound is fresh, while one that does is bad. If there is no sound, it means the air cell and yolk are intact. A sound indicates the egg might be old.
Three Shines: Gently hold the egg against a light source to observe it. A good egg has a clear, translucent egg white and yolk, with a small air cell at one end. If the egg is not fresh, it will appear dull and have a larger air cell. Old or spoiled eggs may have stains. Additionally, to determine if eggs you've already bought are fresh, you can use the water test. Place the eggs in fresh water; those that sink with the pointed end down are fresh. If the eggs you bought are not particularly dirty, it's best not to wash them. Store them in the refrigerator with the smaller end down.