EFFECT OF VOLATILE OILS MIXTURE AND LASER RADIATION ON LIPID OXIDATION AND SHELF LIFE OF BEEF SAUSAGE DURING CRYOPRESERVATION

The aim of this research is to study the chemical components of cinnamon, rosemary, and clove volatile oils by GC/Mass as well as the antioxidant activity of these oils and their mixture by DPPH scavenging to select the best volatile oil or mixture for preparing beef sausage treated with laser rays (Helium-Neon laser wavelength 632.8 nm for 9 min for each side). Also, to study the effect of volatile oils mixture at 500 ppm and laser radiation on lipid oxidation and shelf-life of beef sausage during cold storage. Results indicated that 23, 10, and 18 compounds were identified from cinnamon, rosemary, and clove which represented 97.26, 98.50 and 98.80 %, respectively. Cinnamaldehyde, 1, 8 Cineole, and Eugenol were the most abundant chemical compounds in cinnamon, of cinnamon, rosemary, and clove volatile, respectively. Volatile oils mixture had significantly higher antioxidant activity than each volatile oil individual but significantly lowers than BHT as a synthetic antioxidant substance at all studied concentrations. Lipid oxidation (peroxide value, thiobarbituric acid, and acid value) of sausage treatments were not affected significantly by laser irradiation or volatile oils mixture immediately after processing (at zero time) but affected (p<0.5) during cold storage. Sausage treated with both laser irradiation and volatile oils mixture had significantly lower peroxide value, thiobarbituric acid and acid value than other sausage treatments at any time of cold storage. Also, laser irradiation plus the addition of volatile oils mixture caused high storage stability which increase the shelf-life of sausage to 20 days at 4±1ºC compared with sausage treated with volatile oils mixture only (15 days), sausage treated with laser rays only (10 days) and control sample (5 days).