Monitoring chlorpyrifos-methyl residues in milk, and its persistence during refrigeration storage and milk processing using Elisa [electronic resource].

Includes references.

An enzyme-linked. immunosorbent assay (ELISA) was used for the determination of chlorpyrifos-methyl (Ch.M.) in cow's milk and its persistence during refrigeratipn storage and milk processing. The procedure is sufficiently simple for plant use,rapid, uncomplicated and sensitive (0.02 .ppb ). (Ch.M.) roncentration was linear from 0.05-1.0 ppb. Same day and day- to-day (over a two-month period) reproducibility was excellent with percent coefficients of variation (%CV) ranged from 2.1 to 8.6 % with most below 3 %. Chlorpyrifos-methyl was detected in 10 % (2/20) of the examined milk samples. The percentage of loss in ( Ch.M.) residues reached (15 %) after 3 days of refrigeration storage. The maximum loss of-(Ch.M.) residues was-achieved during yoghurt mak1ng (90%); followed by soft cheese making (40 %), ice-cr-eam processing (35 % at - 2°C and 33 % at -20°C); no marked difference was observed between freezer and deep freezer temperatures, boiling (32 %) and then pasteurization (20 % ).

Summary in Arabic.

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