This "chaotic child" is the earliest preserved egg. Mixed with charcoal ash and lime, coated on eggs, the ingredients of eggs were chemically changed by strong alkaline substances, and sealed for 5735 days, so that the yolk and protein were fused together. Later, there was a formula of "Cowhide Duck" in "The Preface to Raising the Remnant Moon" written by Dai in the late Ming Dynasty: Cowhide Duck: twelve ounces of salt, five liters of chestnut charcoal ash, and one liter of lime, which was used every hundred times, and the salt was put into the altar as usual. Once every three days, * * * three times and sealed in January.
Fang Yizhi, a thinker and scientist in the early Qing Dynasty, put forward that "the universe (time) rotates in the universe (space)", holding that "the universe is in the universe and the universe is in the universe" and called preserved eggs "color-changing eggs": "Chizhou (now Tongling, Anhui Province) produced color-changing eggs, which were mixed with five kinds of ash and salt, and buckwheat grains were yellow and white. Adding charcoal lime to the furnace is green and tough. " Fang Yizhi believes that eggs will undergo different chemical changes and form two different products when different charcoal ashes are used. Fang Yizhi also believed that this kind of "metamorphosis" was developed on the basis of ancient "immortals". Before he described "changing eggs", there was a passage: "The notes of Laoxue Temple and Qi Yaomin's book have the method of hanging salted eggs to dye duck eggs. Today, Wu people use the method of root stains of Polygonum cuspidatum. "
Look up "Notes on Old Ann Studies" Volume 5: The Book of Qi Yao Min has the method of salted hangzi, which uses hangzi skin to soak duck eggs. Today, it is also an ancient method for Wu people to dye the roots of Polygonum cuspidatum. "Tao Tui Geng Lu" also records: "Xianhangzi is now called Xianhangzi, and rice soup is mixed with salt and grass ash to form duck eggs. According to "Qi Yao Min Shu", there is a flood of Hangmu bark here, hence the name. "Check the Book of Qi Yao Min again, Volume 6:" Hang the bark, wash the thin stems, and cook the juice (add a liter of salt when cooking, and the juice will be extremely cold in the urn (Jia Sixie explained that if the juice is hot, the eggs will rot and not last long). Dipped duck can be eaten in January, cooked and eaten for both wine and food. If the salt is cut, the egg will float (if the salt penetrates, the egg will float by itself). "
So what is Hangmupi? Jia Sixie said: "Erya said:' Hang, fish poison.' "Guo Pu (pú) Note:" Hangzhou tree, like chestnut, was born in the south, with thick skin and red juice, and hidden eggs and fruits. "If there is no hanging skin, Polygonum cuspidatum root cattle (suspected to be wrong) will work together. Er Ya said, "Tea: Polygonum cuspidatum. "Guo Pu's Note:" Like red grass, thick and prickly, it can be dyed red. "Jade Piece" explains "Hang": "The name of a tree gives birth to a jade chapter. Frying juice, hiding fruits and eggs is also good. " Shen Ruyun's Record of Foreign Bodies: "Hangzi is sonorous, and salted duck is also used, so it is pickled with Hangmu bark juice. This is everywhere in my hometown today, but it is like Xanthium sibiricum and beneficial mother, and the stem is not pure wood. Little people fight and rub their skin (ruó) with leaves to make it red and swollen, so as to falsely accuse their enemies. Speaking of hiding duck eggs, the outside is dyed and looks like ochre. " Yang Wanli has a poem: "Deep red Hangzi light red fish (ZH m: a kind of fish pickled with salt and red yeast) is rare in Jiangxi." Hangpi juice is red and can be preserved and dyed. Duck eggs pickled with Hangpi juice are red in skin, so they are also called "Hangzi". Jue Liao Jue's Miscellaneous Notes: "Southerners harvest ducks with salt, which is called salty hangzi." It can be seen that "salted duck eggs" are salted duck eggs.
Hangpi is also alkaline. It is natural and reasonable to say that salted duck eggs are the premise of preserved eggs.
In the Qing Dynasty, preserved eggs were recorded in more detail. "Tune": "Duck eggs are painted with salty sand, watered with ash when they are dry, and then yellow and straight. To be a gray salt duck, it will be yellow in the middle of the month, otherwise it will be biased. " Mix hair ash with water to make the yellow pigment of Salsa penetrate into the eggshell, and print and dye the eggs. Plant ash salt produces strong alkali, and then protein condenses into amber translucent colloid, which turns the yolk blue-black. The saying that "yellow works once every half month" is based on the tidal principle. On the first and fifteenth day of the lunar calendar, the moon and the sun are the most attractive to the earth. At this time, the yellow of duck eggs can be in the middle, and at other times it will deviate.
At this point, the proportion of ingredients has been clear. Summary of Agriculture, Mulberry and Food: Duck eggs are made into balls with twelve ounces of salt and three liters of ash every hundred. "Complete Collection of Household Necessities": "Sift the kitchen ash into two parts, one part of salt, and mix well. However, duck eggs are soaked in thick rice soup, rolled with gray salt and stored. " "Wake Up the Garden Record": "Use four pieces of lime, charcoal ash, pine and cypress ash and ridge sugar ash (lime must be less, not equal to each piece of ash), add salt and mix well, stir and mix with strong tea, neither hard nor soft, and wrap the eggs. Put it in the jar and seal it with mud. It can be used for 100 days. Its salt can only be used for two cents per egg. Too much salt is too salty. Another method: divide reed grass and straw ash into two parts and lime into one part. First, use a cypress leaf belt to grind it very fine, mix the mud with the three ashes evenly, add ridge sugar and mix it evenly, mix it with strong tea juice and plastic eggs, put it in a jar for half a month and eat it for twenty days. " The production at this time is not much different from today. The chemical reaction of the cypress leaf belt is in the egg, and its pattern is now called "Songhua".
In the Qing Dynasty, Zeng Yi's Zhong said: "The charcoal ash used to make preserved eggs must belong to the blacksmith's shop. Charcoal made of tin ware must be real chestnut charcoal (charcoal made of chestnut trees), so chestnut charcoal ash is most suitable for making eggs. After the lid is made, it is black but not spicy and tastes the best. Lime must be broad ash (caked strong alkaline high-quality quicklime), first developed with water, and then seasoned with screened charcoal ash and crushed fine salt. If there are ten bowls of charcoal ash, the lime is halved and the salt is halved. Pour it into a pot of strong tea, stir well, and use it for wet and dry purposes. After the eggs are washed and wrapped, they are rolled up with rice chaff and can be put into the jar in about 20 days. "
Preserved eggs are as delicious as salted duck eggs in Gaoyou. Gaoyou, a place where ducks are produced, lays big and light eggs. "Suiyuan Food List" said: "Gaoyou preserved eggs are the best, and the color is fine and oily, and Gao Wen Duangong likes them best. During the dinner, first take it to honor the guests and put it on a plate. It is always recommended to cut the shell and use both yellow and white. You can't leave it yellow and white, so the taste is incomplete and the oil is scattered. " Gaoyou preserved eggs are made of lime, pine and cypress ash, bean straw ash and salt, as well as black tea ash and birch. After it is made, the protein is transparent and the eggs are yellow-green. Kangxi's Gaoyou County Records: Preserved eggs are "preserved with medicinal materials, with colors like honey and lines like pine leaves, which is especially good".
Yiyang, Hunan Province also has good preserved eggs. There are two kinds of folklore about Yiyang's invention of preserved eggs. It is said that a farmer built a house with a lime pool behind it. At night, ducks put their eggs in the lime pool. Later, the owner found in the lime pool that the yolk had solidified after peeling, and the mystery of making preserved eggs was discovered. There is an old man who runs a teahouse. Every day, he dumps the leftover tea leaves on the straw ash pile at the door. His ducks like to lie here and lay eggs at night. The old man later found that there were eggs in the ash, peeled them and tasted them. Without salt, he soaked them in salt water. It will be salty in a few days, that is, preserved eggs.