Salt-brining of mushrooms can effectively increase product added value.
When fresh mushrooms @#@136@#@ poorly, or the price is low, and they need to be preserved for a long time before sale, salt-brining is the simplest and most effective method. Mushroom salt-brining requires no large fixed capital investment, generally about 200 yuan is enough, and the processing technique is relatively easy to master.
1. Materials: washing vat, color-protecting vat, blanching pot, cooling water vat, salting vat and other containers, plus auxiliary materials such as salt and citric acid.
2. Fresh mushroom preparation: the standard is timely harvesting, removing debris and cutting stems, and sorting by grade.
3. Washing and color protection: fresh mushrooms can be directly soaked and washed in 0.6% salt water, washing while protecting color; after washing, put them into a citric acid solution with a pH of 4-4.5 to soak and wash, which can inhibit the mushroom bodies from turning brown or black.
4. Blanching and cooling: so-called blanching means quickly cooking fresh mushrooms in boiling water to avoid aging of the mushroom bodies, opening of the caps, etc., so as to keep their original shape and at the same time expel part of the water inside the fresh mushroom tissue, opening the pores wider so that salting proceeds more smoothly. Bring 10 degrees Baume (about 10%) light salt water to a boil, put in the color-protected fresh mushrooms, stir gently with a large slotted spoon so that the fresh mushrooms turn up and down or rotate in the water, generally about 5-10 minutes, depending on the fresh mushroom variety and size, with cooking through as the standard. The cooked mushrooms will sink to the bottom in cold water; immediately scoop them out and put them into a cooling vat, cool quickly with running water, or cool by transferring between vats; after cooling thoroughly, scoop them out and place them in bamboo baskets or turnover boxes to drain before salting.
5. Salting processing: when salting at home, put the cooled mushrooms into the salting vat in a layer about 20 cm thick, sprinkle a layer of salt on top, with a mushroom-to-salt weight ratio of 4:1, one layer of mushrooms and one layer of salt until the vat is full, then pour in brine with a Baume degree greater than or equal to 23 and adjusted with citric acid to pH 3-3.5, sprinkle another layer of salt on the very top to cover the mushrooms, then cover with a round bamboo mat or similar item, press clean stones on top, and make all mushroom bodies immersed in the liquid. (Brine at 23 degrees Baume and pH 3-3.5 is acid-adjusted saturated salt solution; the pH is tested and adjusted by gradually adding citric acid.)
Transfer between vats once every 2-3 days, repeating the above operation. Generally, salting is completed in about 10-20 days, then it is packed into barrels for sale.
Regardless of the processing volume, any leftover unused salt solution should be stored for later use and must not be discharged at will; otherwise, first, it pollutes the environment and soil, and second, it is too wasteful. It can be left standing in a pool (vat) to let it evaporate, and then used again whenever needed next time.
6. Barreling: generally 50 kg plastic barrels are used, or packaging provided by the buyer is used according to the buyer's requirements; after filling the barrel to the rated weight, pour in a saturated solution with a pH of 3, then sprinkle a layer of salt to seal the opening, tighten the barrel lid, and it is ready as a commercial product.
7. Salt-brining of oyster mushrooms: ① Raw material. Oyster mushrooms at eight-tenths maturity, with caps 3-8 cm in transverse diameter, not broken, and free of foreign matter. Cut off the stems, leaving only 1-2 cm. ② Soaking and washing. Put them into 0.6% salt water, soak and wash them clean, then scoop them into 4% citric acid and soak for about 10 minutes. ③ Blanching. Prepare 10% salt in a stainless steel pot and adjust the pH to about 4; after putting in the oyster mushrooms, stir gently and cook thoroughly, but do not overcook; cook only until done. After cooking through, immediately scoop them into a cooling vat, cool by transferring between vats or with running water to near water temperature; for example, if surface water is 16°C, cool until the inside of the mushroom bodies is about 20°C. Then scoop out and drain. ④ Salting. The mushroom-to-salt ratio is calculated on the basis of fresh mushrooms; for 100 kg of fresh mushrooms, the amount used is 25-28 kg; spread one layer of oyster mushrooms and sprinkle one layer of salt, using slightly less salt in the lower part and gradually increasing the amount of salt in the upper part; prepare in advance a saturated salt solution with a pH of 3, fill the pool (vat), sprinkle another layer of dry salt on top as a cover, then cover tightly and press firmly. ⑤ Transferring between vats. During the Spring Festival period, transfer between vats once every 5-7 days. ⑥ Packaging. Weigh the salted dried mushrooms into designated plastic barrels; after filling, inject brine at 25 degrees Baume and pH 3, sprinkle a layer of salt on top as a cover, tighten the barrel lid, and they are ready for sale.
8. Salt-brining of button mushrooms: ① Raw material. After harvesting button mushrooms, grade them according to contract requirements and cut off the stems, remove all foreign matter, and promptly put them into 0.6% salt water to soak and wash, the same as for oyster mushrooms. ② Blanching. Thoroughly washed and color-protected fresh mushrooms are put into a blanching pot and cooked through. Signs of being cooked through: first, the mushroom bodies sink immediately when put into cold water; second, when cut open, the inside and outside are basically the same color, both pale yellow; third, by feel, the mushroom bodies are elastic when pinched by hand; fourth, by taste, cooked mushrooms are crisp, while half-cooked ones are sticky. ③ Cooling. The cooked mushroom bodies must immediately be put into a cooling vat and quickly cooled with running water. ④ Color setting. The cooled button mushrooms are scooped out; placed in turnover boxes or on bamboo mats to drain, and then they can be put into 15 degrees Baume brine for pre-salting, which is color setting. The color-setting process generally lasts 5-8 days. ⑤ Salting. After pre-salting and color setting are completed, salting can be carried out: prepare a salt solution of 23 degrees Baume or more and pH 4, put in the button mushrooms, cover and pickle; transfer between vats (pools) once every 2-3 days, repeating the above operation; after transferring between vats 2-3 times, salting is completed. ⑥ Storage or barreling. For salted button mushrooms that need to be transported out for sale, they can be barreled; after filling to the rated weight, inject brine at 23 degrees Baume and pH 3-3.5, add salt to seal the opening, tighten the barrel lid, and they are ready for sale.