Microbial hazards assessment during white cheese production in a traditional dairy plant

Abstract EN

This study has been conducted to determine the microbiological contamination sources during production of white soft cheese in a local dairy plant, in Alexandria city, Egypt.

A total of 180 representative samples ( coming raw milk, cheese vat, cheese mould, wooden tables, cheese handler ,water supply, wall, plastic package and white soft cheese) 20 of each.

The trials repeated 3 times to ensure the most contaminated points.

The highest total mesophilic bacterial count was found in Cheese mould with 9.4×106± 3.7×104 cfu/cm2 followed by Plastic package with 2.1×106±3.6×104 cfu/ cm2.

The most contaminated point with coliforms was cheese vat with a mean count of 6.1×104 ± 1.11 ×103 followed by cheese handler with a mean count of 5.6×103 ± 1.8 ×102.

The most contaminated point with a total psychrotrophic count was cheese vat with a mean count of 4.5×105 ± 6.4×104 followed by water supply with a mean count of 3.7 ×105 ± 1.9×104.

The highest S aureus count was found in cheese handler by 9.4×104 ± 5.6×103 followed by the wall with a mean count of 8.5×103 ± 2.3×103.

Enterococci count contaminated wooden table with a mean value of 2.8×104 ± 1.3×102 followed by water supply with a mean count of 1.3×103 ± 4.7×102.

The most contaminated point with yeast and mould was cheese mould with a mean count of 5.8×103 ± 1.3×102 followed by wooden table with a mean count of 3.4×103±1.6×102.

The most contaminated points which affect the microbial quality of white soft cheese during processing were cheese mould followed by wooden table, cheese handler and cheese vat.

The application of the hygienic measures for manufacturing of the dairy products greatly improves their quality.

The hygienic measures include cooling of the milk, heat treatment, use of clean water, personal hygiene of cheese handler, sterilization of equipment and prevent of post contamination during manufacture.

A HACCP – based risk assessment and good manufacturing practice should be employed for all stages of manufacture of soft cheese.