Effect of catechins extract of green tea (Camellia sinensis ) in growth of some bacteria and an attempt to useit in meat preservation

Abstract

This study was carried out to detect the effect of aqueous and catechins extract ofgreen tea (Camellia sinensis) in the growth of some pathogenic and spoilage bacteria,and attempting to use themin preservative of meat. Results showed high significantdifferences p<0.05 between aqueous and catechin extract .Catechins effect showedhigh significant p<0.05 toward Pseudomonas aeruginosa in compare with theaqueous extract. However no significant differences were detected between theextracts towards Salmonella typhi and Staphylococcus aureus. Aqueous and catechinsextract were added in concentrations of (100, 300 and 900) ppm to the minced meatand stored at a temperature 4C° for 15 days.Results showed that low increasing in the peroxide value was reported whenconcentrations of 300 and 900 ppm were used, while a concentration of 100ppm wasnot enough to reduce the peroxide value. However, control samples showed anincrease in the peroxide values with extending the period of storage. When thevolatile nitrogen was evaluated, results showed that using a concentration of 900ppmgave the greatest affect, while no significant influence of green tea ( aqueous,catechins ) extracts with a concentration of 100ppm was shown . Total bacterialcounts of minced meat was also determined .Results showed that Green tea extractshad the greatest effectiveness in preventing the development and growth ofmicroorganisms when a high concentration of (900ppm)was added. The results alsoshowed that green tea extracts had the highest effectiveness in preventingdevelopment of chemicals changing and growth of microorganisms when highconcentration (900ppm) was added and less effect at a concentration of (100ppm). Itcan be concluded that the catechins of green tea could be used in preservation andextending the shelf life of meats.