Postharvest treatment of Pleurotus ostreatus

Pleurotus ostreatus, also known as Pleurotus ostreatus, is a kind of artificially domesticated wild strain, which has a trend of gradual expansion in recent years. Its mushroom taste is fragrant, the meat is crisp and tender, the palatability is good, the output is high, the price is high, and the economic benefit is very considerable. However, the preservation time of its fresh products is short and it is not easy to store. If it is not sold in time, it will cause huge losses. In order to ensure the economic benefits from loss, this paper introduces the salinization processing and dry processing technology of Pleurotus ostreatus.

1. Salting processing of Pleurotus ostreatus

1. Harvest. The mushroom body of Pleurotus ostreatus for salinized export should be mature at 6-7, that is, the cap is bell-shaped and the bacterial membrane is not broken. Scrape off the silt from the mushroom foot with bamboo slices and wash it clean.

2. Kill the youth. Put the cleaned mushroom body into 5% salt boiling water and boil the 8~12min. The specific cooking time should be determined according to the size of the mushroom body, until the mushroom body is cooked but not rotten, and the center of the mushroom body is thoroughly cooked. The "sinking and floating method" can be used for testing, that is, after a short cease-fire, the mushroom body sinks to be ripe and floats for a living, or the mushroom body is put into cold water, and the cooked mushroom sinks and the raw mushroom floats. After cooking, fish out.

Quickly put in cold water or running water to cool until cold through. Green cooking with aluminum pot or stainless steel pot, do not use iron pot, so as not to affect the quality of mushroom color browning.

3. Pickling. First prepare 40% saturated salt solution, which is called refined salt 40kg, dissolve in 100kg boiling water and cool. Then remove the boiled and cooled mushroom from the water, put it into a clean vat, inject saturated salt water into the flooded mushroom body, and press the bamboo weight to prevent the mushroom body from discoloration and corruption. After the cover, sprinkle a layer of salt on the surface to protect the color and anticorrosion, and then sprinkle another layer after the salt is deepened, so repeatedly until the salt is insoluble.

4. Rotating cylinder for storage. Big ball cover mushroom pickled in concentrated salt water for about 10 days to turn to the tank, re-inject saturated salt water, cover, sprinkle salt until the salt concentration in the tank is stable at 24 Baume degrees, then it can be stored in barrels and sold for export. The salt water after processing can be recovered by heating and evaporation for recycling.

5. Edible Pleurotus ostreatus with salted water. Salted mushrooms can generally be kept fresh for about 3 months. When eating, the mushroom body is removed from salt water, soaked and desalted in clear water, and can be cooked and eaten; salted mushrooms can also be soaked in 1% citric acid solution for 7min desalination, and rinsed clean with clean water after fishing, without salt when cooking, so as not to increase salinity.

2. Dry processing of Pleurotus ostreatus

The water content of the mushroom body of Pleurotus ostreatus is high, so it is not suitable to be processed by sun-drying. it is suitable to choose dryer or electric blast dryer for mechanical drying in the drying room.

1. Grading and sieving. The mushroom body of the dried Pleurotus ostreatus should stop spraying water 2 days before harvest, scrape off the scales of the mushroom body and the sediment of the mushroom foot with bamboo slices, retain the stalk as needed or cut off all or part of the stalk with stainless steel scissors, drain the water under ventilation after cleaning, or let it dry in the sun for 2 hours, screen and grade according to the size and degree of dryness and wetness of the mushroom, and put the pleats down on the baking screen. Preheat the dryer (room) to 45: 50 ℃ before baking, wait for the temperature to drop slightly, then put the fresh mushroom sieve on the drying rack of the drying room, large and wet mushrooms discharge the middle layer, small mushrooms and dried mushrooms discharge the top of the sieve, open the umbrella mushroom to discharge the bottom of the sieve. After the discharge, close the baking door and turn on the machine for baking and drying.

2. Adjust the temperature and set the shape. The initial baking temperature of mushrooms picked in sunny days was 35-40 ℃, and that of mushrooms picked in rainy days was 30-35 ℃. After the mushroom body is heated, the surface water evaporates rapidly. at this time, all the air intake and exhaust windows should be opened to discharge water vapor with the maximum ventilation, so as to make the whole fungus fold piece fixed and shaped upright. Then lower the temperature to 26 ℃ and keep it for 4 hours to prevent the bacterial pleats from lodging, damaging the mushroom shape, blackening the color and reducing the commodity value.

3. The mushroom body is dehydrated. The baking temperature of 26 ℃ was kept for 4 h, and the baking temperature was increased by 2: 3 ℃ per hour. The constant temperature was maintained from 6 to 8 h to 51 ℃, which promoted the evaporation of water in the mushroom body. When heating up, the air window should be opened and closed in time, and the relative humidity should be adjusted to 10% to ensure that the bacterial folds are upright and the color is fixed. In the heating stage, the position of the upper and lower drying screen should be properly adjusted to make the drying degree of the mushroom body uniform.

4. Dry as a whole. When the constant temperature rises slowly from 51 ℃ to 60 ℃ for about 6 hours and 8 hours, when baking to 80% dry, it should be taken out and dried for 2 hours and then baked on the shelf, the double air windows should be fully closed for 2 hours, baking until the handle is easily broken by hand, and the baking ends when it makes a crisp sound. Generally, 9kg fresh mushrooms can be processed into 1kg dried mushrooms.

5. The finished products shall be packed separately. The dried dried mushrooms were packed in plastic food bags according to grade, each bag containing 500g or 1000g dried products, sealed, stored or exported. The dried products of Pleurotus ostreatus can also be loaded into woven bags lined with plastic film, sealed and placed into corrugated cartons or autocratic bamboo and wooden boxes, each box containing dry products 5kg, which is not only convenient for preservation, but also conducive to export.