Variations in microbial load of raw milk and influencing factors form dairy farms to collection centers of Esferayen area

Subject Areas : Food Science and Technology

عبداله Jamshidi ¹ , رضا Vakili ² , حسام Seifi ³ , جواد Hajizadeh ⁴

1 - Associate Professor of Food Hygiene and Aquatic animal Health Departement, Faculty of Veterinary Medicine, Ferdowsi University, Mashhad, Iran
2 - Assistant Professor of Animal Science Department, Kashmar Branch, Islamic Azad University, Kashmar, Iran
3 - Full Professor of clinical Science Departement, Faculty of Veterinary Medicine, Ferdowsi University, Mashhad, Iran.
4 - Graduated of Animal Science, Kashmar Branch, Islamic Azad University, Kashmar, Iran.

Received: 2012-06-17 Accepted : 2013-07-17 Published : 2012-11-21

Keywords: Bulk-raw-milk, total bacterial count, Esferayen,

Abstract :

   Raw milk is among the highly perishable foods which are subjected to various environmental contaminations following milking. In this study, the factors influencing bacterial load of bulk-milk were investigated. For this purpose, 100 samples were obtained from dairy farms around Esferayen during spring, summer and autumn of 2009. The samples were taken in three stages: after milking, before transportation from dairy farm, and before delivering to milk-collection-center. The samples were analyzed for total bacteria count (TBC). To determine the factors which could influence the TBC of raw milk, a questionnaire sheet where designed. Statistical analysis were performed by means of logistic regression (genmod procedure), using SAS software (version 8.2). According to the results of this study, maintaining cold chain throughout the transportation and storage of raw milk, prevention of mastitis, cleaning and sanitizing of containers and equipments, age and breed of dairy cattle as well as indirect factors such as education level of dairy farmers, distance to milk-collection-center had significant effects (P<0.05) on microbial count of bulk-tank-milk. It was concluded that to reduce bacterial in raw milk, it is crucial to maintain cold-chain throughout milking process, wash teats with sanitizers, improve the hygienic condition of the milking utensils as well as to improve the overall quality of personnel education.

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