THE QUALITY OF BULK TANK MILK AND ASSOCIATED MANAGEMENT PRACTICES IN THE MANGAUNG METROPOLITAN MUNICIPALITY, SOUTH AFRICA

Abstract

Milk has played a huge role in human diet across the world and has been the most accessible food product over the years. Necessarily, moves have arisen with the intention to improve its quality. Some factors that are necessary in improving the quality of milk are, amongst others; the hygiene of food handlers, transportation of milk, storage of milk and the possible diseases that can be transmitted. In farms and commercial outlets, food handlers, transportation, storage and the possible disease that can be transmitted through milk at a low temperature until it can be transported to outlets, for further processing or markets; however, at times bulk tanks are used as a point of sale. In, South Africa, a considerable number of people tend to consume raw milk originating from cow, sheep and goat that is not pasteurised. Moreover, there have been reports that some people alter milk by combining pasteurised milk with raw milk or by adding water to increase the quantity of milk thereby increasing their profit whilst decreasing the quality of milk. This milk is also consumed mostly by farm families as it is the only source of calcium that is affordably accessible to them. The current study was conducted over a period of a year, where fifty four (54) milk outlets where identified by authorities (Environmental Health Practitioners) from the Mangaung Metropolitan Municipality for microbial and physicochemical analysis. However, only 28 outlets were operating during the study when questionnaires were administered. A case study of five (5) different dairy farms was also conducted to follow up milk quality from the production point to the point of final sale to the public (farm to fork). All samples were obtained from bulk tank milk by pouring milk directly into the sterile glass bottles, transported to the laboratory on cold ice to maintain the cold chain and analysed for both microbiological (indicator microbes) and physicochemical parameters. These bottles were marked according to the shop names and transported to the laboratory immediately for analyses. Questionnaires were also distributed and administered at outlets selling milk to assess food handlers’ attitude, knowledge and practices, questionnaires were explained to the respondents and responses kept anonymous for openness of respondents who may be uneasy about the process and outcomes. The latter was crucial as most outlets were owned or co-owned by foreign nationals and most felt uncomfortable with the study thinking that the intent was to close them down and/or report them to the authorities. The results showed that out of 28 outlets were questionnaire was administered, 63% of outlets had lack of knowledge about the required cooling temperature of milk, more especially when milk arrived at the outlets. The survey further indicated that Escherichia coli were present in 54% of outlets and this was found in all the outlets in Thaba-Nchu and this area represented 32% of the entire study. Thirteen percent (13%) of outlets showed adulteration of milk whilst 94% showed non-compliance of coliform counts in the areas of the study. Total Viable Counts were high in 76% of outlets and these shops were not complying with the regulation, and this was followed by 41% non-compliance when focusing on somatic cell count (SCC). These results indicate poor personal hygiene and lack of proper production practices. The identified levels of indicator microorganisms have a potential to cause quick deterioration of milk which will affect human health, causing possible diseases such as severe infections and gastrointestinal infections. The study further revealed that bulk tank milk fat content was high in 6% of outlets and ethanol content was also found in 17% of outlets. This indicated non-compliance, possibly from poor hygiene practices and possible milk adulteration. Although inhibitory substance and protein content complied in all studied areas, only 26% outlets showed that pasteurisation was not done and this is known to limit the shelf life of milk. The study further showed that in five dairy farms where the case study was performed, temperature of the tankers used to transport milk was high and not complying with the standard (not above 5°C) at two farms (farm 1 and 3). Moreover, it was found that in one farm (farm 4), the temperature of the milk was not at the correct temperature level and thus not complying with the standard. Furthermore, the study showed that milk in one of the farms (farm 1) was not pasteurised. SCC were above the acceptable levels (500 000cfm-1) at the farm and during transportation in farm 2. This suggested that farm management practices were neglected and economic loss will be experienced by these farmers or bulk tank owners if they cannot trace back the source of contamination. On the other hand, the study found out that 64% of food handlers in these outlets were females and 79% were black workers who mostly did not receive proper training on food safety issues. Forty six percent (46%) of food handlers had working experience of 5-10 years, with 57% having an education level that ranges between grades 7-12. The study further showed that 93% of food handlers reflected a lack of knowledge and poor handling of milk on aspects such as the impact of hands on contaminating the milk. The importance of cleaning bulk tanks properly and the use of effective disinfectant are crucial in order to have milk that is less contaminated. The study revealed that 80% of food handlers ignored general hygiene practices. Although 100% reported that they used hot water to wash the equipment, only 32% used the required sanitizers to wash the milking equipment. Ninety three percent (93%) of the outlets have never replaced the bulk tank and this may also contribute to milk not complying with minimum standards according to Regulation relating to dairy milk and milk products (R1555 of 1997), especially in the light of possible formation of biofilms. Factors such as ignorance, low morale and attitude of food handlers can greatly affect and compromise food safety aspects and thus affect the quality of milk. Therefore, it can be recommended that Environmental Health Practitioners (EHPs) should visit commercial outlets on a monthly basis to evaluate the hygiene practices and the conditions of the outlets as well as provide training to all people handling milk a practice not fully followed. Finally, an awareness programme must be provided to all food handlers on a quarterly basis; and this must be for the farmers, owners of outlets and food handlers. It will further be of great interest to investigate other microbial and physical components of milk to identify possible pathogenic strains concomitant to analysis done quarterly.