Research Phd Theses

Research: Milk safety and quality in Rwanda

According to Olivier Kamana, head of the department of Food Safety and Food Quality Management at the University of Rwanda, the livestock sector, which includes the dairy sub-sector, plays a crucial role in the Rwandan economy. To ensure economic strength, it is important therefore to ensure food safety and quality. For this reason, Kamana conducted a story to provide detailed information on microbiological quality and safety of milk and milk products all along the production chain. His particular focus was Salmonella.

The study found that the quality of dairy products assessed was acceptable; however, quality decreased slightly at collection centers. Quality in processing facilities varied wildly and was dependent on the facility’s size. Small plants, for instance, were more prone to offering product of poor quality, said Kamana.

“In the small plants it was noted that the total mesophilic count (TMC) and coliforms in milk were slightly decreased after pasteurization, which indicates ineffective pasteurization and/or post-contamination, resulting in unacceptable microbiological quality of pasteurized milk and derived dairy products according to the international and local standards,” said Kamana.

Inadequate refrigeration further deteriorated product quality at the supermarket level.

The study uncovered several significant bottlenecks throughout the supply chain, including small cheese processing plants and milk shops that sell boiled and traditionally-fermented milk.

During the course of the study, hygiene status was also assessed. Weaknesses were found in similar locations, including small cheese plants and milk shops. “Post-study, there were noticeable improvements regarding microbiological safety of cheese,” said Kamana. “And it was revealed that personnel hygiene and the processing environment are probably the origin of occasional Staphylococcus aureus and Salmonella contamination during processing.

The study also confirmed that applied heating treatments enable the total elimination of Salmonella.

“An exposure assessment to Salmonella revealed that the interventions carried out in the cheese sub-sector by the government after the high prevalence of Salmonella in cheese (2012) allowed the reduction of the risk of salmonellosis by 30% per year in the case of cheese consumption by adults,” explained Kamana. “It was also found that seven consumers were likely to get infected each day and 680 consumers per year after consumption of boiled milk in milk shops in Musanze town.”

Olivier Kamana received his PhD in the Department of Food Safety and Food Quality in the Faculty of Bioscience Engineering at the University of Ghent in Belgium. Today, he is a lecturer and head of the Department of Food Safety and Food Quality Management at the University of Rwanda.