Assessment of the Efficiency of Petrifim Method in Study of Bacteriological Quality of Some Homemade Dairy Products in Local Market of Basra

Abstract

The aims of this study were assess the bacteriological quality of homemade milk products available in Basra city and to assess the performance of the Petrifilm method in the enumeration of microorganisms for dairy samples compared with conventional pour plating techniques. Comparisons for total aerobic plate count (APC), Lactic acid bacteria total coliform count and Escherichia coli count were done for 180 raw milk samples, 180 yogurt samples and 180 cheese samples. Samples were taken from local market of Basra during a 12-month project. This study has shown that these products have high levels of total aerobic bacteria, total coliform and E. coli which may be attributed to the absence of hygienic quality during production and storage because these products are usually produced by using traditional methods regardless of the quality of the raw milk used or the sanitary quality of the product. Significantly higher total coliform and E. coli were observed in raw milk, yogurt and cheese samples using Petrifilm compared to the pour plating technique (P < 0.05). However, no significant differences (P > 0.05) were found between APC pour plating method and Petrifilm during enumeration total aerobic plat count and lactic acid bacteria for all dairy samples.  The study has shown that petrifilm is faster, more accurate and easier to use in counting microorganisms than conversional methods, which takes time to prepare and requires plates and other facilities. Therefore, we believe that the use of petrifilm methods in counting microorganisms for all kinds of foods is useful for saving time and effort compared to traditional methods.

Keywords: Petrifilm, Milk products, Lactic acid bacteria, Coliform, E. coli, Cheese