Utilization of Fruit by-Product in Ground Meat Preservation

Meat is prone to both microbial and oxidative spoilage, therefore it is desirable to use a preservative with both antioxidant and antimicrobial properties. The use of fruit by-products such as Grapefruit rind powder (GRP), orange rind powder (ORP) and mandarin rind powder (MRP) with or without ? irradiation on microbial growth, lipid oxidation and color change of raw ground beef meat stored at 4 ± 1 0C was evaluated. Also, the effect of these natural by-products on the survival of Salmonella typhimurium, Escherichia coli and Bacillus cereus inoculated into sterile ground beef meat was studied. All by-product additives significantly (p< 0.05) reduced total bacterial, lactic acid bacteria and total mold and yeast counts and extended the shelf-life of ground meat compared with the control. The control samples were microbiologically rejected on day 7 of storage at 4 ± 1 0C. The counts of pathogenic bacteria inoculated into ground beef meat were significantly (P< 0.05) affected by the addition of additives. MRP showed high antimicrobial effect flowed by ORP then GRP, these results confirmed with the microbial tested of shelf-life of ground meat. The gram-positive bacteria (Bacillus cereus) were more resistance than gram-negative bacteria (Salmonella typhimurium and Escherichia coli) for tested treatments. It was also found that ORP had the highest scavenging effect (%) on DPPH followed by GRP then MRP. Concerning lipid oxidation, the control showed significantly (p< 0.05) higher malonaldehyde (MDA) content during all storage period and the color components were significantly (p< 0.05) affected by the additives used. The results of this study suggest the potential for developing natural food additives from fruit by-product for improving food stability, quality and safety. Key words: By-product, ground meat, ? irradiation, antimicrobial and antioxidan