How are preserved eggs made? Are there any downsides to eating too much?

Preserved eggs, also known as preserved eggs, are a traditional flavored egg product unique to China. People who eat them for the first time find them pungent and unpleasant, and difficult to swallow. People who eat them for a long time find them smooth and refreshing, with a unique flavor. , the charm of preserved eggs lies in this, people will fall in love with it as soon as they eat it.

Some people also call it bian egg. In fact, strictly speaking, there is a difference between preserved egg and bian egg. Bian egg is a specialty of Henan. It is made from pickled eggs. The egg white is golden and transparent, and the yolk is thick. It is thick liquid, while the white of preserved egg is dark brown and clear, and the yolk is solid or semi-solid. Preserved eggs have always been a favorite delicacy of many people, so how are they made? Let’s find out together below! How are preserved eggs made? Are they nutritious?

This question needs to be answered in two parts. One is how to make it? Second, is it nutritious? The process of making preserved eggs is a complex chemical change process. Let’s first talk about whether they are nutritious, and then learn more about how to make them and what to pay attention to.

1. The nutritional value of preserved eggs

First of all, preserved eggs are made from duck eggs. The nutritional value of duck eggs is well known, so preserved eggs are definitely nutritious. According to research It shows that under the action of alkali, enzymes, etc., the protein of preserved eggs is decomposed into simple proteins and amino acids that are more easily absorbed by humans, and the amino acid content is as high as 32 mg (content per 100g), which is more than ten times the 2.8 mg content of fresh eggs. In addition, In addition, preserved eggs also contain a variety of nutrients such as protein and vitamins. Among them, they are rich in iron and have a certain blood-enriching effect. The ammonia and hydrogen sulfide produced by protein decomposition can promote digestion and increase appetite.

According to the "Yilin Compendium" records, the preserved egg is derived from the eggs of ducks of the Anatidae family and is developed from lime, grass ash, salt, etc. Its nature and flavor are pungent, astringent, sweet, salty, and cold. , has the functions of purging lung heat, removing fire, and treating diarrhea.

2. Key points for making preserved eggs

Preserved eggs are a delicacy that many people like. They can be used to make porridge, soup, salad, etc. Making preserved eggs can be said to be simple or complex. , it’s simple because of how to make preserved eggs. If you talk about how to make preserved eggs, people who have done it will say that it is very simple. It is to use quicklime, plant ash, salt, alkali, tea water and other ingredients in proportion to make a paste, and then apply it on the pickled duck eggs. , leave it for about half a month. It is complicated because the transformation of duck eggs into preserved eggs is a complex chemical reaction process. Simply put, it is made by reacting alkaline ingredients with the amino acids in the protein in the eggs. In order to ensure the preservation of preserved eggs, The production is successful, but there are still a lot of details that need to be taken care of. Let’s take a look.

①Selection of duck eggs

Making preserved eggs is a slow process, and in this process, the quality of duck eggs is crucial. Only high-quality duck eggs can make preserved eggs. , so, what kind of duck eggs should be chosen to ensure preserved eggs?

1. Look, first of all, you need to check whether there are any cracks on the surface of the duck egg. Secondly, the surface of the eggshell is not smooth, and whether the air cells on the surface of the eggshell are obvious or not. If there are cracks on the surface, it is very rough, and there are air cells on the surface. Obviously, it cannot be used as it is easy to break during production.

2. Touch, in addition to looking, you must also pass your hands. If during the touching process, you find steel-shell eggs (very hard) or sand-shell eggs (soft-shell eggs), you cannot choose them. Steel-shell eggs contain too much salt. It is difficult for salt and alkaline to penetrate into the egg, while sand shell eggs are easy to break, so be careful when selecting.

3. Listen, what does Duck Egg need to listen to? Just hold the duck egg to your ear and shake it, and listen to see if the sound is loose yolk eggs. Everyone should know this. No matter what kind of eggs you make, loose yolk eggs cannot be used.

4. Fresh, yes, eggs can be divided into fresh and aged eggs. In fact, eggs also have a shelf life. The shelf life is also different depending on the storage environment temperature. Generally, it is about 15 days at room temperature in winter and at room temperature in summer. The next week or so, the refrigerator will keep it fresh for about a month. Fresh eggs generally have a layer of frosty powder on the surface, and the eggshells look bright and feel pressed in the hand.

②Preparation processing

After buying duck eggs, there will generally be a lot of impurities attached to the surface. Of course, they cannot be pickled directly. They need to be cleaned before proceeding to the next step. However, making preserved eggs Unlike other eggs, it is not recommended to wash them directly with water, and it is best not to use eggs stored in the refrigerator because you are worried that moisture will enter the eggshell through the air chamber, which will lead to unsuccessful pickling. So what should you do?

1. You cannot wash it directly with water. You can use a wet towel to wipe the surface of the eggshell. If it is difficult to remove the substance, use a knife at an angle of 30°C and scrape it off along the arc of the eggshell. If it is dirty, If the material is not treated cleanly, it is easy for bacteria to breed.

2. Place the cleaned duck eggs in a cool and ventilated place to dry to prevent the moisture remaining on the surface from not drying for a long time and entering the eggshell. (Do not let direct sunlight shine on the duck eggs)

③Prepare the paste

This step is to prepare the paste that turns the duck eggs into preserved eggs. Whether the paste is well prepared will directly affect the success of the preserved eggs. , if the comparison is not mastered well, the preserved eggs will either not be shaped or become watery, so the slurry needs to be prepared according to a certain proportion. The main ingredients for pickling preserved eggs are quicklime, alkali, plant ash, salt and tea leaves. Taking 50 duck eggs as an example, 200g of quicklime, 50g of alkali, 700g of plant ash, 60g of salt and 5g of tea leaves will be used. Of course, pickled preserved eggs There are many ways to make it, so the ingredients and quantities used must be different. This is just a reference value. Let’s take a look at how to prepare it.

1. Put the tea leaves into a large bowl, add an appropriate amount of boiling water, brew the tea leaves into strong tea, then filter out the tea leaves and only take the tea water. (The tea needs to be cooled before it can be used, because it requires a chemical reaction with quicklime)

2. Put the quicklime, alkali, plant ash, and salt into a basin and stir evenly, then slowly add the tea into the basin. , make it into a paste that is neither thin nor thick. (Pay attention to safety when adding tea, because quicklime and water will produce a lot of heat, so don’t splash your eyes or hurt your hands)

④ Pickled duck eggs into preserved eggs

This step is also to make The step in the transformation of duck eggs from liquid to solid is a complex chemical reaction process. Simply put, it is the chemical reaction between soda ash (containing sodium carbonate), plant ash (containing potassium carbonate) and lime (containing calcium oxide). The strong alkali sodium hydroxide and potassium hydroxide then penetrate into the eggshell and react with the protein, which in turn decomposes the amino acids. When the sulfur-containing protein reacts with the amino acids, it is released as hydrogen sulfide. This is preserved egg. The source of the special smell. At the same time, the strong alkali will further neutralize the amino acids decomposed from the protein. The resulting salt crystals will be deposited in the solidified egg white, and white cypress leaf-like needle-filled pine flowers will appear. Songhua eggs are also Hence the name.

Quick lime, soda ash and plant ash are important ingredients that produce chemical components that turn duck eggs into preserved eggs. Salt can accelerate the coagulation of egg whites, inhibit the reproduction of microorganisms in the eggs, cause the eggs to shrink and shell after they are formed and solidified, and also It has the functions of flavor enhancement and preservative. Tea contains more pigments, tannins, aromatic oils and alkaloids, which can assist coagulation, increase color, and neutralize the alkaline spicy taste of preserved eggs.

1. Put the dried preserved eggs into the prepared slurry, wrap it evenly, then put it into the rice husk and wrap it again. (This layer is for protection, you can also use bran or sawdust)

2. Put the wrapped duck eggs into a plastic bag, then exhaust the air, tie the mouth tightly, and place it in a cool and ventilated place , take it out in about two weeks, open it for ventilation and annealing to reduce the spicy smell of preserved eggs. (Preserved eggs cannot be blanched and pickled all the time, otherwise they will easily decompose into water again under strong acid. Take them out to let them breathe for a week or so, and the preserved eggs will be ready)

The above is the general process of making preserved eggs and all the ingredients. Details that need to be paid attention to. Making homemade preserved eggs seems very simple, just adjust the slurry and marinate. In fact, there are many tips that need to be paid attention to. Practical operation

Preserved eggs are a relatively common delicacy in life. Although many people don’t like the taste, there are also many people who like it. Especially a plate of cold preserved eggs has a high rate of appearance at the dining table. , a must-try dish for drinking and eating.