Composition standard:

Duck egg 100, quicklime 1 kg, soda ash 0.35 kg, salt 35 g, star anise 25 g, pepper 25 g, pine and cypress branch 1, monosodium glutamate 5 g, black tea powder 5 g, chaff and plant ash.

Second, the operation process of making preserved eggs

1. First put pepper, star anise, pine and cypress branches into a pot, add 0.5 kg of water and cook for half an hour, then add salt and black tea powder and cook for 5 minutes, then add monosodium glutamate, stir, take out and filter to get juice. When the juice is slightly cool, add quicklime and soda ash, and fully stir until it is completely dissolved.

2. Grab 8 ~ 10 by hand, add plant ash and stir into a paste. Dip the selected fresh duck eggs in the paste to make them stick to the paste, then roll them on the chaff and seal them in the jar. If you put the egg can at room temperature of 30℃, it only takes 7 days to mature and get out of the can. After being taken out of the can and dried, it can be sold or boxed (stored).

Third, lead-free preserved eggs

1. Lead oxide (yellow lead powder) is added to the traditional preserved egg processing formula in China. As lead is a toxic heavy metal element, some countries have banned its sale, which has affected the export of preserved eggs in China.

2. For this reason, the relevant scientific research departments have studied the substitute substances of lead oxide, among which EDTA and FWD are better. When EDTA (ethylenediamine tetraacetic acid) is used, the formula and processing technology of other auxiliary materials remain unchanged, as long as lead oxide is removed and EDTA is used instead. Generally processing 1000 duck eggs, the dosage is 0. 12 ~ 0. 13 kg. FWD is a substance synthesized by trace elements magnesium and manganese. Its usage is to dissolve 0.5 kg FWD in 75 kg cold boiled water to make 1500 duck eggs. The formula and processing method of other auxiliary materials are the same as when lead oxide is used.

Four, preserved egg quality inspection commonly used methods are: one observation, two weighing, three shaking, four taking pictures.

One view: Look at whether the packaging material is moldy, whether the eggshell is complete and whether the shell color is normal (the green cylinder color is better).

Second, put the egg in your hand, gently throw it up and throw it several times in a row. If you feel elastic and trembling, the heavier egg is a good egg, otherwise it is a poor egg.

Three shakes: hold both ends of the egg with your thumb and middle finger, shake it up and down in your ear, and hear the sound of water or impact. If you can't hear the sound, it's a good egg.

Photo 4: If most eggs are black or dark brown and a few are yellow or light red, they are high-quality eggs. If most of them are yellow-brown transparent body, they are immature preserved eggs.