EVALUATION OF DIFFERENT METHODS OF DRYING ON THE QUALITY OF OYSTER MUSHROOM (Pleurotus sp)

Mushrooms are extremely perishable and have a short shelf life period. To increase the post harvest lives, different methods of drying viz., sun diving, fluidized bed drying and thin layer drying with potassium metabisulphite (KMS) and blanching was done. The quality of mushroom dried in fluidized bed condition at 50°C for 80-120 minutes with 0.5 KMS was found to be superior to other drying methods. Rehydration ratio was also maximum in KMS treated mushroom and no significant difference at higher concentration. The treatment with KMS and blanching reduces the nutritive quality but improves the colour of the mushrooms when compared with sun dried samples. Storage of mushrooms after treatment with KMS at higher concentration (1.5%) reduces the microbial spoilage.