Effect of thickness of polyethylene packaging and temperature on quality of solar-dried oyster mushroom (Pleurotus sajor-caju)

Abstract

Pleurotus sajor-caju is evaluated as an edible fungi with high nutritional and medicinal value, but fresh mushrooms are easily damaged after harvest due to many reasons. Drying methods can be taken to maintain mushroom quality, reduce losses and prolong postharvest storage time. The objective of this study was to evaluate the effects of polyethylene (PE) packaging thickness (91.70 μm; 81.30 μm and 53.50 μm), temperature (28-30 oC and 3- 5 oC) (with air humidity of 60-62% and 76-78% respectively), to the quality of oyster mushrooms dried by solar energy, during storage. During the storage period, the total sugar and protein contents of all treatments decreased. Besides, the colour (through the difference in lightness and darkness (ΔL) value) and firmness of the solar-dried oyster mushrooms also decreased, so, oyster mushrooms were darkened and softened. After 6 months, the lowest protein, total sugar and lipid loss was found in PE packaging of 91.70 μm thickness at storage temperature of 3 oC-5 oC. In addition, the water activity of dried mushrooms was lower (less than 0.7), so it ensures microbiological safety.