Shelf-life evaluation of ostrich meat.

摘要

This research has been divided into two experiments. In first experiment, effect of packaging atmospheres on the shelf-life of ground ostrich meat (GOM) was evaluated. GOM was packaged in high oxygen (O2), high nitrogen (N2), vacuum (VAC) and air (AIR) packages, and evaluated for shelf-life characteristics, pH value, color properties (L*, a*, b*, hue angle, chroma and total color difference-ΔE), oxidative changes (Thiobarbituric acid value, and hexanal content) and microbiological examination (Total viable cell, Coliform, Lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp.) over 9 days of storage at 4 ± 1°C under 1700 ± 101 lux lighted display. All packaging methods had similar effects on microbial growth. Total viable cell counts reached 107 CFU/g meat between 3 and 6 days. TBA values and hexanal content were the greatest in O2 package, and lowest in VAC and N2. GOM was below saleable quality in less than 6 days based on any of the meat attributes.; The second experiment evaluated the effects of oxygen permeability of films, sodium lactate, and rosemary extract on the shelf-life of vacuum packaged ostrich patties. Treatments were the addition of 0.02% rosemary extract (AO), 2.0% sodium lactate (SL) and mixture of 0.02% AO and 2.0%SL (MIX) vacuum packaged with high oxygen transmission rate (OTR) (4000 cc) or low OTR (3–6 cc) packaging films. Meat samples were stored at 3 ± 1°C in the dark for 9 days. The pH, TBA value, color properties (L*, a*, b*, hue angle, chroma, ΔE and reflectance difference-ΔR_630–580), and microbial quality (Total aerobic, Coliform, Lactic acid bacteria, and Brochothrix thermosphacta) of ground ostrich patties were determined. Microbial growth were slowed by addition of SL to ostrich patties and provided 2 log reduction in microbial population during storage in both package types. Low OTR packages and AO had better color stability and higher a* values before and after opening the packages as compared to high OTR packages. Based on microbial quality of meat, untreated patties packaged in low OTR films reached 107 log CFU/g meat after 6 days stored at 3 ± 1°C. Best results were observed in SL added samples in low OTR packages since counts remained below 107 log CFU/g meat.