The traditional process of making fish sauce is exposure and fermentation. Fishermen usually put fresh fish and shrimp and appropriate amount of water in a vat and expose them in the sun. After 3 to 6 months, liquid will flow out, and then they can add appropriate amount of sugar, garlic, pepper and lemon to taste, thus making fish sauce. This production process can be done by fishermen in coastal areas. It is a very traditional method that marine fish are fermented and distilled by adding salt.
In order to speed up the fermentation of fish sauce and shorten the production cycle, in some places, enzyme live fish offal is added when making fish sauce. Because it is rich in proteases, such as trypsin, chymotrypsin and cathepsin, it can accelerate the decomposition of protein, thus shortening the fermentation cycle.
II. Production process of fish sauce
Raw material-salting-fermentation-enzymolysis-filtration-filtrate-blending-bottling-sealing-finished product
Operating points:
1. Raw material selection
Fish with high protein content, tender meat and good flavor after fermentation should be selected as raw materials, such as fresh fish, eel, seven-star fish and triangle fish.
2. Salting
Put the newly caught fresh fish into a soaking pool. The fish with large strips need to be minced with a mincing machine first, then add 3% ~ 4% of the weight of the fish, stir evenly, seal each layer with salt, and marinate for six months to one year. In the meantime, it is necessary to stir for many times to make the salted fish contain 24% ~ 26% salt.
3. Fermentation enzymolysis
Fermentation can be divided into natural fermentation and artificial fermentation. Production enterprises can adopt different fermentation methods according to the actual situation.
natural fermentation is the fermentation of fish with its own enzymes and microorganisms at room temperature. Generally, the fermentation pool is built outdoors, and the pickled fish are put into the pool, making full use of natural climate and solar energy, and fermenting by sun exposure. In order to make the fermentation temperature uniform, it is stirred once every morning and evening, and the degree of fermentation depends on the content of amino acids. When the increase of amino acids tends to zero, and the fermentation broth is fragrant and delicious, it is the end of fermentation, which usually takes several months.
Artificial fermentation is the fermentation with sandwich insulation pool, and the temperature is controlled at 5O-6℃ in water bath. After half a month to one month, the fermentation is basically completed. In the meantime, it is stirred by a compressed air machine, so that the raw materials are heated evenly. In order to accelerate the fermentation process, protease can be added to accelerate protein decomposition. Commonly used proteases include bromelain, papain, trypsin and complex protease, and the fermentation period can be shortened by half.
4. Filtering
After fermentation, the fermented mash is filtered by a bag filter to separate the fermented liquid from the residue.
5. Leaching
The filtered residue can be treated by nested leaching, that is, the first filter residue is soaked with the second filter solution, the second filter residue is soaked with the third filter solution, and so on. When leaching, the leaching solution is added to the residue, stirred evenly, soaked for several hours, and the amino acid is dissolved as much as possible, filtered and leached again, and repeated several times until the amino acid content is lower than 2g/L.. Finally, the filter residue is boiled with salt water, cooled and filtered to be used as leaching solution for later use.
6. Blending
The fish sauce after leaching is mixed and blended according to different grades, and the thinner fish sauce can be concentrated in a concentrating pot to evaporate some water, so that the amino acid content and other indicators can reach the national standard.
7. bottling
The prepared fish sauce with different grades is respectively bottled in glass bottles which have been cleaned, disinfected and dried in advance, sealed and labeled, and then the finished product is obtained.
Precautions:
1. The salt content of pickled fish should be determined according to the nature of the fish itself. If the fat content is high or the fish body is not fresh, the salt content can be appropriately increased to avoid fish body corruption.
2. When adding enzymes to promote protein decomposition, we should master the characteristics and action conditions of the enzymes used. The optimum pH value of bromelain is 4 ~ 6, and the temperature is 4 ~ 5℃. The optimum pH value of papain or trypsin is 7 ~ 8, and the temperature is 35 ~ 5℃. The optimum pH value of the complex protease is 7, and the temperature is 45 ~ 5℃. Production enterprises can choose the appropriate enzymatic hydrolysis method according to their own specific conditions.