IMPROVEMENT OF SHELF-LIFE AND WHOLESOMENESS OF GROUND-BEEF BY IRRADIATION .2. CHEMICAL-ANALYSIS AND SENSORY EVALUATION

Lean ground beef was exposed to three dose levels of gamma radiations (Cobalt-60) (1.0, 2.5 and 5.0 kGy). Chemical indices monitored through out the storage period (16 days, 4-degrees-C) included pH, free fatty acids and peroxides. Irradiation clearly contributed to a diminution o f the pH and an increase of the peroxides. Free fatty acids were not a ffected. The 10 non-expert panellists indicated a noticeable effect of irradiation on the odour and colour of the raw product. The odour and flavour of the irradiated cooked ground beef was slightly disliked wh ile no difference was perceived in the colour and texture of the cooke d irradiated ground beef. Following these considerations, it is recomm ended that ground beef be treated with a low dose (such as 1 kGy).