INHIBITION OF OXIDATIVE RANCIDITY IN FROZEN COOKED FISH FLAKES BY TERT-BUTYLHYDROQUINONE AND ROSEMARY EXTRACT

The antioxidant properties of tert-butylhydroquinone (0.5 g kg-1 + 20 g kg-1 ascorbic acid-TBHQ-AS) and an extract of rosemary (2.5 g kg-1) alone and in combination were determined by their addition as solutions to cooked fish flakes stored at - 20-degrees-C. Oxidation was measured by following changes in free fatty acids, thiobarbituric acid number, fatty acid composition and sensory evaluation. The order of effectiveness in inhibiting oxidation was TBHQ-AS > combination > rosemary > untreated control - 70-degrees-C > untreated control - 20-degrees-C. Sensory evaluation indicated that green aroma and flavor notes were associated with the rosemary extract, while fish oil notes were associated with untreated samples.