Knowledge, Handling Practices of Consumers, and Microbiological Safety of Processed Milk Products Sold in Nairobi County

Abstract

Milk products are considered a main source of dietary nutritional requirements for all people of all age groups in Kenya, especially the infants, pregnant women, the sick and the immune compromised individuals, with an aim to improving their health. However, poor knowledge and inefficient handling practices may make milk products a source of food borne diseases. Additionally, unpasteurized milk is a potent bacterial growth medium and a significant source of bacterial infections. The current research aimed at assessing the knowledge, handling practices of consumers and microbiological safety of processed milk products sold in Nairobi County, determining consumers’ knowledge and handling practices of Milk and milk products, establish the prevalence of TVC, E. coli, Staphylococcus aureus and Listeria monocytogenes microorganisms’ contamination on processed milk and milk products and determining implementation of GMP in milk processing systems by the processors for control of the above microorganisms. In addition, it aims at creating evidence-derived awareness and providing continuous education especially for vulnerable groups regarding the risks associated with pathogens in milk products. Data was collected through structured questionnaires and was administered through face-to-face interviews and then analysed using SPSS. The Fisher’s formula was used to get the sample size where 360 consumers were randomly selected. Furthermore, samples of fresh milk, yoghurt cheese and ice creams were collected from supermarkets and prepared for analysis of microorganisms. Purposive sampling technique was used in selecting processors brands of milk products at the point of sale in the 3 different study areas and a total of 36 samples were analyzed. Ten processing facilities were also purposively selected to assess the level of implementation of food safety management systems such as ISO 22000, GMPs, and HACCP. Fresh milk was the most consumed milk product at 94% closely followed by yoghurt (93%) with ice cream and cheese trailing. About 69.9% of the respondents consumed fresh milk on daily basis, while 53.7% consumed yoghurt on weekly basis, 37.3% rarely had yoghurt and just about 27% of the respondents indicated that they had ice cream while majority (65.2%) indicated they rarely consumed ice cream. More than 91% of the respondents boiled milk before use while nearly 90% of the respondents used milk for tea preparation. It was also noted that most of the respondents (59%) owned a fridge and out of these, 15.6% boiled milk to make it last longer while 39.6% used it immediately. Furthermore, chi-square tests showed an association between the education levels of milk consumers and their parametric choice on good quality milk (P=0.000). Of the samples collected in Karen, ice cream had the highest contamination level of TVC (3.26 log 10 CFU ml -1). Ice cream samples from Langata had the highest Total Viable Count contamination levels at 4.35 log 10 CFU ml. The overall prevalence of E. coli in milk and milk products was 41.6% with a mean count of 0.34 log 10 CFU ml -1 in Karen, 0.07 log 10 CFU ml -1 in Kibera and 0.11 log 10 CFU ml -1 in Langata while Staphylococcus aureus xv was detected in 33.3% of the milk and milk products. It was also observed that all the milk processors tested for total viable counts (TVC), and E. coli while only 50% and 33.3% of the processors tested for S. aureus and L. monocytogenes respectively. Majority (83.3%) had well-documented cleaning programs and had a system of controlling cross contamination which was enforced through different colour codes (66.7%), memos and notices (16.7%) and through colour coding of processing equipment (16.7%). In conclusion, the majority of respondents had a level of knowledge viewed as sufficient about the milk processing and temperature. Despite the fact that majority of milk processors had implemented good manufacturing practices (GMP) and conformed to good processing practices, regulators need to encourage and emphasize on the routine analysis of the other food pathogens such as the Staphylococcus aureus and Listeria monocytogenes through routine surveillance. There is also need to improve the microbial quality of milk products by employing measures that will establish proper management practices to ensure improved hygiene, good manufacturing practices and food systems that will help to minimize microbial contamination