Effect of dietary vegetable oil combined with vitamin E supplementation and gender on the pH and colour of rabbit meat and dissected fat

Abstract

Often less than optimal PUFA content of human diet have started the research aimed to increase its quantity in meats. Including linseed and sunflower oil in rabbit feed effectively improves rabbit meat lipid composition, but its altered sensitivity to oxidative reactions could result in colour change. The effect of vegetable oil content of the diet and vitamin E supplementation was studied on the colour of rabbit loin and thigh meats and dissected fat. Meat lightness, redness, yellowness, hue and chromacity were measured with Minolta chromameter on samples cooled to 5 °C for 24 h. Including sunflower (2%) and linseed (2%) oil in rabbit diet changed the colour of the dissected fat making it lighter (L* 76.96 v. 73.79), more yellowish (b* 13.34 v. 11.41) and intense (C* 14.49 v. 12.35) coloured compared to the control diet without vegetable oils. To the effect of the vitamin E supplementation of vegetable oil containing feed redness of the thigh decreased (a* 4.41 v 5.44) and hue increased (h° 58.63 v. 49.76). The source of vitamin E supplement influenced only the colour of loin: natural vitamin E increased lightness (L* 53.03 v. 49.62), yellowness (3.86 v. 3.04) and chromacity (3.96 v. 3.25) while synthetic vitamin E did not. The changes of loin, thigh and fat colour observed in this study may be utilized in making the product more desirable to the consumer.