Studies on coliform organisms in milk and some dairy products

Eighty random samples of market raw milk, pasteur-ized milk, fresh cream and Damietta cheese, collected fromdifferent localities in Cairo and Giza, wero bacteriolo-gically cx~mined for detection, isolation and classifica-tion of coliforms as well as typing of existing E. coli.All examined samples of market raw milk provod tobe conbamf.nsrt od ’’Ii th coliform organisms c.t titres rangingfr’)[1 10-3 to 10-9 (average 10-6.l~5). Tho maximum coliformcontent (HPN/100 m1) in exnmined s emp.Lcs WaS 172 x 108,the minimum Was 130 x 103, with an average of 188 x 107.The hiGhest frequency distribution (50%) lay within therange 107 - 109; the mode w~s 108•The coliform content in samples collected frommilk-shops and street salesmen was hiGher than in sampleso bt ained from dairy farms.Coliforms wore present in 40% of cXRmined samplesin past eurizod milk, as they could be dot.ected in 1 mlof 15% of samplos, in 0.1 ml in 20% of samples and in0.01 ml in 5% of samples. The coliform MPN/IOO ml variedfrom 80 to 700, with an average of 262.5.Examination of market cream revealed detection ofcoliform organisms in all samples at varying titres ranging .