Effectiveness of mānuka and rosemary oils as natural and green antioxidants in wagyu and normal beef

Abstract

Essential oils possessing antioxidant characteristics have acquired broad interest as an alternative to synthetic food antioxidants like butylated hydroxytoluene (BHT). In this study, m anuka (with 5, 25 and 40% triketone content) (MO), rosemary (RO) and k anuka (KO) oils were characterised and screened through DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (Ferric radical absorbing power) assays for their antioxidant efficacies. Different triketone levels were selected to examine their effect on the antioxidant activity of MO. All MOs showed higher phenolic content and antioxidant activities than KO and RO. Based on the obtained results, the MO with 25% triketone content and RO were chosen to study their antioxidant effects in pastes prepared from New Zealand normal (3% fat) and wagyu (12% fat) beef during refrigerated storage (7 days). No significant effect of the oils was observed on lipid oxidation in normal pastes during storage. However, MO and BHT significantly reduced lipid oxidation in wagyu pastes, showing the potential of m anuka oil as a natural antioxidant in high-fat meat products.

Mānuka Oil vs. Rosemary Oil: Antimicrobial Efficacies in Wagyu and Commercial Beef against Selected Pathogenic Microbes

“…Regarding the chemical composition of the meat pastes, wagyu paste contains 64.8% moisture, 12.3% fat, and 19.4% protein. However, commercial beef paste had lower fat content (3.4%) and higher- moisture content than wagyu beef, as reported by our recent paper [ 48 ]. The moisture content of the meat paste samples was checked according to the method of AOAC [ 49 ].…”

“…Among the three MOs, only MO 2 with 25% triketone content was chosen to examine its antimicrobial effect against microbial growth in the meat systems. This selection was based on the results of preliminary experimentation involving the thermostability, antioxidant [ 48 ], and antimicrobial characteristics of these oils. As RO inhibited Gram-negative ( E. coli and Salmonella ) and Gram-positive bacteria ( S. aureus and L. monocytogenes ) at 2.5% concentration; thus, the same concentration of MO was selected to compare their antibacterial effect.…”