| Popis: |
Response surface methodology was used to evaluate the quantitative effects of three independent variables: rapeseed moisture content, concentration of the added enzymes and conditioning temperature, on the antioxidant capacity and total phenolic, tocopherol, and phospholipid contents in the enzyme-treated rapeseed oils. The highest antioxidant capacity (1220.0, 964.8 μmol TE/100 g) total phenolic (83.3, 74.0 mg SA/100 g) and phospholipid (12,532, 12,376 mg/kg) contents reveal two rapeseed oils extruded from seeds contained 11% moisture, treated with cellulolytic and pectolytic enzymes (0.05%), respectively, and heated at 120 °C. However, the highest content of total tocopherols was determined in rapeseed oils pressed from seeds with 7% moisture, after addition of cellulolytic (0.05%) and pectolytic (0.1%) enzymes, heated at 90 and 105 °C, respectively. Total phenolic and phospholipid contents in the enzyme-treated rapeseed oils correlated significantly ( p R 2 = 0.8710 and 0.6581, respectively). Experimental results of the antioxidant capacity, total phenolic, tocopherol and phospholipid contents were close to the predicted values calculated from the polynomial response surface models equations ( R 2 = 0.9727, 0.9870, 0.8390 and 0.9706 for the cellulolytic enzyme-assisted rapeseed oils and R 2 = 0.9148, 0.9489, 0.9426 and 0.9479 for the pectolytic enzyme-assisted rapeseed oils). The optimum rapeseed moisture content, enzyme concentration and conditioning temperature for the cellulolytic and pectolytic enzyme-treated rapeseed oils were 11% and 9.7%, 0.08% and 0.1%, and 120 °C, respectively. |
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