Optimization of Freeze-Drying Process Parameters for Qualitative Evaluation of Button Mushroom (Agaricus bisporus) Using Response Surface Methodology

摘要

Button mushroom cubes of constant cross-sectional area (0.75?cm × 1.5?cm) and varying thickness (2?mm, 5?mm, and 8?mm) were freeze-dried. Pressure (0.04, 0.07, and 0.10?mbar), primary drying temperature (?2°C, ?5°C, and ?8°C), and secondary drying temperature (25°C, 28°C, and 31°C) were taken as drying parameters. The protein, ascorbic acid, and antioxidant contents were taken as quality estimates for freeze-dried mushrooms. It was observed that the secondary drying temperature affected the protein () and antioxidant content () significantly, whereas all three freeze-drying parameters affected the ascorbic acid content with higher effect due to temperature parameters () as compared to pressure (). The optimized values for protein, ascorbic acid, and antioxidant content obtained using response surface methodology were ?mg/g, ?mg/100?g, and ?mg/g, respectively, as compared to ?mg/g, ?mg/100?g, and ?mg/g, respectively, for fresh button mushrooms. The optimum values for process variables were obtained as 0.09?mbar, 0.36?cm, and ?7.53°C and 25.03°C for pressure, sample thickness, and primary and secondary drying temperatures, respectively.