Keywords: Agaricus bisporus, heat penetration, mushroom curry, postharvest technology, retort pouches, white button mushrooms, core temperature, bacterial contamination, curried mushroom
Heat penetration characteristics of mushroom curry packed in retort pouch
White button mushrooms (Agaricus bisporus) in curry, packed in retort pouches were heat-processed in a pressurised autoclave. Retort pouches (105 µ thick) used had an outer polyester layer (12.5 μ), a middle aluminum layer (12.5 µ) and an inner cast polypropylene layer (80 µ); size 20 cm×16 cm; seal size 10 mm and lip size 4 mm. Adequate number of pouches were fixed with glands to insert the thermocouples for recording core temperature of mushrooms using data recorder and computer connected to each other. The mushroom curry was heat-processed to F0 value of 10.3 (time in minutes at 121°C) and heat penetration parameters were calculated. The heating curve obtained was logarithmic in nature and the processed mushrooms were free of bacterial contamination and had desirable sensory attributes. The pouches withstood the pressure and temperature of the retort without delaminating, shrinking or wrinkling and the curried mushroom was found to be sterile over a one year storage period.