How to Process and Handle Stropharia rugosoannulata After Harvest

Stropharia rugosoannulata, also known as the wine cap stropharia, is a domesticated wild mushroom species, and in recent years there has been a trend of gradual expansion. Its mushrooms have a delicate fragrance, crisp and tender flesh, good palatability, high yield, high selling price, and very considerable economic benefits. However, its fresh product has a short storage life and is not easy to store, and if not sold fresh in time, huge losses will be caused. In order to ensure that economic benefits are not lost, the salt-preservation processing and dried-product processing techniques for Stropharia rugosoannulata are now introduced. I. Salt-preservation processing of Stropharia rugosoannulata 1. Harvesting. The fruiting bodies of Stropharia rugosoannulata used for salt-preserved export should be harvested at 6~7 maturity, that is, when the cap is bell-shaped and the partial veil has not yet broken. Use a bamboo slice to scrape off the soil and sand from the mushroom base, and wash them clean. 2. Blanching. Put the cleaned fruiting bodies of Stropharia rugosoannulata into boiling water with 5% table salt and blanch by boiling for 8~12 min. The specific boiling time should depend on the size of the fruiting bodies, and boiling should continue until the fruiting bodies are cooked but not mushy and the center of the fruiting bodies is thoroughly cooked. The "sink-float method" can be used for testing, that is, stop the heat for a moment; if the fruiting bodies sink, they are cooked, and if they float, they are raw; or place the fruiting bodies into cold water; cooked mushrooms sink and raw mushrooms float. After boiling is completed, scoop them out and quickly place them into cold water or running water to cool until thoroughly cold. Use an aluminum pot or stainless steel pot for blanching and boiling, and absolutely do not use an iron pot, so as to avoid browning of the fruiting body color and affecting quality. 3. Pickling. First prepare a 40% saturated salt water solution, that is, weigh 40 kg of refined table salt and dissolve it in 100 kg of boiling water, then cool. Then scoop the boiled and cooled Stropharia rugosoannulata out of the water, place them into a clean large vat, pour in saturated salt water until the fruiting bodies are submerged, and press bamboo slices and heavy objects on top to prevent the fruiting bodies from being exposed above the salt water surface, discoloring, and spoiling. After pressing and covering, sprinkle a layer of surface salt on top to protect color and prevent spoilage. When the surface salt dissolves and deepens, sprinkle another layer, and repeat this until the surface salt no longer dissolves. 4. Transferring to another vat for storage. After Stropharia rugosoannulata has been pickled in strong salt water for about 10 days, it should be transferred to another vat once, with saturated salt water poured in again, pressed and covered, and surface salt sprinkled until the salt water concentration in the vat stabilizes at 24 Baume degrees, after which it can be packed into barrels for storage and export. After processing is completed, the salt water can be used to recover table salt by heating and evaporation for reuse. 5. Eating salt-water Stropharia rugosoannulata. Salt-preserved Stropharia rugosoannulata can generally be kept fresh for about 3 months. When eating, scoop the fruiting bodies out of the salt water and soak them in clean water to remove salt, then they can be cooked and eaten; the salt-water mushrooms can also be soaked in 1% citric acid solution for 7 min to remove salt, then scooped out and rinsed clean with clean water. When cooking, salt may be omitted to avoid increasing the saltiness. II. Dried-product processing of Stropharia rugosoannulata The fruiting bodies of Stropharia rugosoannulata have a relatively high water content and are not suitable for processing by sun-drying. It is advisable to use a dryer or an electric heated forced-air drying machine for mechanical drying in a drying room. The process is as follows: 1. Grading and loading onto trays. For Stropharia rugosoannulata used for drying, watering should be stopped 2 days before harvest. Use a bamboo slice to scrape off the scales on the fruiting bodies and the soil and sand from the mushroom base. Keep the stipe as needed or cut off all or part of the stipe with stainless steel scissors. After washing, drain the water in a ventilated place, or spread them in the sun to air-dry for 2~4 h. Sort and grade them according to fruiting body size and degree of dryness and wetness, and place them on baking trays with the gills facing down. Before baking, preheat the dryer (room) to 45~50°C. After the temperature drops slightly, arrange the fresh mushroom trays on the tray racks of the drying room: place large and wet mushrooms on the middle layer of the tray racks, small mushrooms and dry mushrooms on the top layer of the tray racks, and opened-cap mushrooms on the bottom layer of the tray racks. After arranging them, close the drying room door and start the machine for baking and drying. 2. Temperature adjustment and shape setting. The starting temperature for baking mushrooms picked on sunny days is 35~40°C; for mushrooms picked on rainy days it is 30~35°C. After the fruiting bodies are heated, surface moisture evaporates rapidly. At this time, all air inlet windows and exhaust windows should be opened to discharge water vapor with the maximum ventilation volume, prompting the entire gill plates to become fixed and stand upright for shape setting. Immediately afterward, lower the temperature to 26°C and maintain it for 4 h to prevent the gill plates from falling over, damaging the mushroom shape, turning black in color, and reducing commercial value. 3. Dehydration of the fruiting bodies. After maintaining 26°C for 4 h, begin to raise the temperature, increasing the baking temperature by 2~3°C per hour and maintaining this for 6~8 h until reaching 51°C, then hold constant to prompt a large amount of water in the fruiting bodies to evaporate. When raising the temperature, open and close the air windows in time and adjust the relative humidity to 10% to ensure that the gill plates stand upright and the color is fixed. During the temperature-raising stage, also appropriately adjust the positions of the upper and lower baking trays so that the dryness of the fruiting bodies is uniform. 4. Overall drying. From a constant 51°C, slowly raise to 60°C over about 6~8 h. When dried to 80% dryness, take out the baking trays and air-dry them for 2~3 h, then put them back on the racks for baking. Close both air windows completely and bake for 2 h, until the mushroom stipe breaks easily when lightly bent by hand and gives a crisp sound, at which point baking is finished. Generally, 9 kg of fresh mushrooms can be processed into 1 kg of dried mushrooms. 5. Finished product packaging. Pack the baked dried Stropharia rugosoannulata by grade into plastic food bags, with 500 g or 1000 g of dried product per bag, seal the bag opening, and store for preservation or export. The dried product of Stropharia rugosoannulata can also be packed into woven bags lined with plastic film, and after sealing the bag opening, placed into corrugated cardboard boxes or specially made bamboo or wooden boxes, with 5 kg of dried product per box, which is convenient for both preservation and export.