الفهرس | Only 14 pages are availabe for public view |
Abstract With the increased demand for high quality, convenience, safety, fresh appearance and extended shelf life in raw fresh white shrimp and fresh meat products, the natural antioxidant and antibacterial activities of mango seed kernel extract (MSKE), Olive leaves extract (OLE) and coriander leaves extract (CLE) were investigated. Phenolic content and ABTS, DPPH were the highest for MSKE, followed by OLE and CLE. Total flavonoids were the highest for OLE followed by MSKE then CLE. The most abundant phenolic components (HPLC) are methyl gallate, naringenin and ellagic acid for MSKE, OLE and CLE, respectively. MSKE, OLE and CLE also showed promising activities against many food-borne pathogens and spoilage microorganisms. Application of MSKE soaking treatments (1 and 2%) for raw shrimp compared with control group, sodium metabisulphite solution group at 1.25% (SMS) indicated that melanosis formation significantly delayed and sensory quality was significantly improved in shrimp treated with 2% MSKE, where increments in bacterial load and thiobarbitutric acid reactive substances significantly decreased. Melanosis score, chemical indices and microbiological status of shrimp immersed in 2% MSKE were less than that treated by 1.25% SMS. The shelf-life of white shrimp was longest for 2% MSKE (10 days), followed by SMS (9 days). Consequently, 2% MSKE could be used as an effective natural antimelanosic agent to inhibit post-mortem melanosis and improve quality. Incorporating in MSKE, OLE and CLE at 2% in raw beef patty formulas indicated that as the time of cold storage progressed, the overall mean scores of physicochemical and microbiological parameters increased, while sensory scores and color parameters decreased. Individual addition of tested extracts significantly (P<0.05) affected color parameters, lipid stability, microbiological loads and appeal to consumers compared to control samples, with the superior to MSKE followed by OLE then CLE, during storage at 4±1°C. Soaking in MSKE at 1% and sodium nitrite at 50, 75, 100 and 125 ppm/kg meat and MSKE (100 ppm+ 1% MSKE; 125 ppm +1% MSKE) were applied and residual nitrite level (RNL) and some quality attributes of raw cured beef sausages were determined during storage up to 30 days. Results indicated that residual nitrite and sensory scores were decreased. This study demonstrated the potential use of MSKE to improve microbial quality, retard lipid oxidation, maintain good color and quality indices and extended the shelf-life of treated beef sausages during 30 days over that of control. |