2. INTRODUCTION
• Mushrooms continue to respire after harvest and they have a relatively high
respiration rate compared to other fresh produce, the respiration rate of oyster
mushroom being three times greater than most fruits
• Spoilage during storage can be caused by bacteria and fungi within the
mushrooms. Bacteria and enzymes continue to increase during cold storage. This
results in rapid deterioration when the mushrooms are removed from cold storage.
• Fresh mushrooms have a short shelf life. Therefore it is necessary that they are
either marketed soon after harvesting or preserved with special care such as in
cold storage or other controlled environment storage.
3. TYPES OF PRESERVATION TECHNIQUES
• Short term preservation
Refrigeration and freezing.
Vacuum-cooling
Irradiation
• Long term preservation
Drying:
Canning
Pickling
Use of chemicals
5. Vaccum cooling
• Uniform and faster.
• Mushrooms are subjected to low pressure and water evaporates giving
off the latent heat of vapourization.
• Gives superior colour then conventional cooling.
Irradiation
• α- radiation to reduce the microbial contamination.
• Should be given immediately after harvest.
6. LONG-TERM PRESERVATION
Drying:-
• Sun dried- 2 to 4 days.
• Packed in polyethylene bags.
• Wooden boxes at 2-5°C for prolonged storage.
Canning:-
Cleaning
Blanching
(2 MIN)
Canning Sterilization Cooling Labelling Packing
(2.5% NaCl
0.2% citric
acid)
(100-120°C
for 1hr)
7. Use of chemicals
• Central food technological research institute(CFTRI).
• 2.5% NaCl, 0.2% citric acid, 0.1% ascorbic acid, 0.1% Sodium
bicarbonate, 0.1% potassium meta-bisulphate.
• mushroom:Solution (1:2)
• Stored at 21-28°C.
