Fresh-keeping Technology of Pleurotus ostreatus

Under general conditions, Pleurotus ostreatus is difficult to store and its shelf life is short. After picking for 2 days, the freshness of Pleurotus ostreatus decreased greatly, and the mushroom noodles turned yellow and appeared peculiar smell. During the peak period of mushroom production, a large number of fresh mushrooms are concentrated on the market, resulting in a big drop in mushroom prices; on the other hand, in the off-season and cities far away from mushroom areas, there is no goods to sell because of the lack of mushroom sources. For this reason, we carried out the study on the storage and preservation of Pleurotus ostreatus, which is briefly introduced as follows.

Test materials: conventional species of Pleurotus ostreatus, PL-32, PL-35, Florida, are all two-tide mushrooms, collected from the mushroom garden of farmers in the suburbs of Gutian County; antistaling agents (anticorrosion and ethylene removal) prepared by themselves; ordinary clean cold storage for storage; refrigerated vehicles for long-distance transportation.

Methods: 80% mature Pleurotus ostreatus was harvested, disease, insect and damaged mushrooms were removed, put in a clean, cool and ventilated place, air-cooled for 1 to 1.5 hours with an exhaust fan, then carefully loaded into plastic baskets of coat PE (thickness 40 ~ 60 μ m), each basket was filled with about 7.5kg, 2 sheets of clean folded toilet paper were placed on the mushroom surface, and a packet of antistaling agent weighing about 40g (packed with well-ventilated shoulder lining paper) was placed on the paper surface. Cover the plastic basket and immediately transport it into a cold storage that has been precooled for 24 hours. When the storage temperature is below 5 ℃, vacuum pump is used to decompress the PE until the PE is tightly pressed to the plastic basket; fasten the mouth of the bag to prevent air leakage and palletizing; then lower the temperature to 1 ±0.5 ℃ for constant temperature storage.

The results showed that after the Pleurotus ostreatus was stored by the above fresh-keeping method for 35 days, the good mushroom rate of the three varieties was more than 99.5%, there was no decay, browning and softening, and the natural loss rate of water was in the range of 0.5%. For the determination of CO2 and O2 content in the final storage environment, the CO2 content in the PE of the three varieties was 9.84%, 10.31% and 2.54%, respectively. Among the main nutritional components of the three varieties, the protein content decreased by 1.07% to 1.16%, the carbohydrate content decreased by 2.0% to 2.5%, and the cellulose content increased by 0.21% to 0.26%. In the control group (the pretreated fresh mushrooms were put into plastic baskets and stored in the same cold storage as the experimental group), the concentrations of CO2 and O2 in the storage environment were stored in the storage atmosphere for 14 days, the decay rate was 10.1%, the mushroom softening rate was as high as 100%, the natural water loss rate was as high as 27.2%, and the edible value was 0. This shows that Pleurotus ostreatus using the above fresh-keeping technology, after the completion of a certain storage period, still basically maintain the original quality.

Three days before storage, the cold storage should be gently warmed up (from 1 ℃ to 10 ℃, if the local @ # @ 136 vegetables, the temperature should rise from 1 ℃ to normal temperature), PE and antistaling agent should be unloaded before shipment, and transported to the place of sale by refrigerated truck (the temperature in the box is controlled at 8: 12 ℃). Practice has proved that Pleurotus ostreatus can overcome the serious dew phenomenon after Pleurotus ostreatus comes out of the warehouse.

Pleurotus ostreatus was packed with plastic basket and PE, and fresh-keeping agent was placed. Through decompression, low temperature and other storage technical measures, a storage environment with high CO2 and low O _ 2 was created, which reduced the respiratory intensity of the mushroom body, reduced the loss of respiratory matrix, prevented the accumulation and synthesis of ethylene, inhibited the activity of polyphenol oxidase, overcome the loss of water, and prevented the infection and reproduction of microorganisms. After 35 days of storage, the good mushroom rate still reached 99.5%, and the main biological arg of the mushroom body was still basically maintained at the level of just harvested, and the preservation was successful.

The technology has the advantages of low investment, simple and easy practice, and quick application in production, and the fresh Pleurotus ostreatus has no drug pollution and meets the hygienic standard.