1. Preserved eggs are made of raw or cooked eggs.
Preserved eggs are made from raw duck eggs, which are wrapped and marinated with quicklime, firewood ash, tea, salt, alkali and other materials for 20~30 days, and then cured and matured by chemical reaction. So preserved eggs can be used directly. Egg maturation is a process of denaturation in protein, but we usually denature eggs by heating, while preserved eggs are made by using chemicals to denature raw eggs.
Second, preserved eggs mixed with tofu preserved eggs should be boiled?
Preserved eggs don't need to be boiled, because preserved eggs are cooked, but the flavor of preserved eggs may be a little strong if eaten raw. If you are not used to this taste, you'd better cook it before eating. When making preserved eggs, lime and alkali need to be added. In alkaline environment, the protein of duck eggs will gradually turn into gel like preserved eggs, and in this process, it will produce odorous ammonia gas.
Third, how to choose fresh preserved eggs
1. Look at the surface of preserved eggs. A well-preserved egg skin is beige, with no black spots or a few black spots, and the whole egg skin should be complete.
2. Weigh the eggs by hand and judge the quality of preserved eggs according to the degree of tremor. Good eggs have great tremor, but the quality without tremor is poor. If you throw a preserved egg on it, it will feel heavier when it falls into your hand, which means that the internal bounce is good and it is a intact preserved egg.
3. Shake the preserved egg beside your ear. High-quality preserved eggs have no sound, and inferior ones have sound. The louder the sound, the worse the quality, and even it has become rotten and smelly.