Studies on thermostable antigens, production of species-specific antiadrenal sera and comparison of immunological techniques in meat speciation.

Heat-stable antigens (BE forms: resistant to heat and ethanol precipitation) of adrenal and muscle tissues of cattle, buffalo, sheep, goat and pig were prepared for use in detection of adulteration in meats. The physico-chemical characteristics of these antigens revealed that the antigens of adrenals had only one component corresponding to 'Troponin T'. Muscle antigens also contained a major troponin T component but were associated with low molecular weight fractions. Rabbit antiadrenal BE sera were developed and made species specific by immunoabsorption. The species-specific antisera were employed for identification of origin of fresh and cooked meats and their mixtures, using an immunodiffusion test-agar gel precipitation test (AGPT), counterimmunoelectrophoresis (CIEP), enzyme-linked immunosorbent assay (ELISA) and the unlabelled antibody peroxidase antiperoxidase (PAP) technique. The results indicated that absorbed antisera could successfully differentiate the fresh, cooked meats and the meat mixtures from the species under study. AGPT and CIEP were useful in identification of 5-10% addition, using water extracts of fresh meats and BE forms of cooked meats, whereas ELISA and PAP could detect adulteration down to the level of 1% when water extracts were used. Among the tests employed in the study, the PAP technique proved to be most sensitive. The antisera were also proved useful in identifying the species in canned meat products, milk, serum, plasma, semen, urine, organs, skin and spoilt flesh, employing AGPT and CIEP.

Preservative effect of combinations of acetic acid with lactic or propionic acid on buffalo meat stored at refrigeration temperature.

A silverside of buffalo was cut in 15 equal-sized steaks and divided into five groups, each group containing three steaks. The steaks from groups 1,2,3 and 4 were treated with 1, 2, 3 and 4% acetic:lactic acid combinations, respectively, and the fifth group was kept as a control. Similar treatments were also given with acetic: propionic acid mixtures. The microbial analysis and changes in colour and odour were noted at 0, 24, 72 and 168 h. The bacteriostatic and bacteriocidal action of the acid mixtures increased with increasing concentration but the effect was reduced as the time advanced. Both acid mixtures had pronounced antibacterial effect on gram negative organisms than gram positive ones. The 3% acetic: lactic acid combination showed reduction in bacterial numbers without affecting the colour and odour of buffalo meat and is recommended for decontamination and preservation of meat for up to seven days at refrigeration temperature (7 ± 1°C).