For better quality milk, chill it as soon as it comes from the cow

Sirikwa Dairies

David Oyolo and Peris Cherotich receive milk from farmers at Sirikwa Dairies in Uasin Gishu County in 2012. When milk is chilled, quality is preserved.

Photo credit: File | Nation Media Group

Demand for milk continues to grow faster, creating a ready market for the produce and its products. However, this ready market has come at a huge price when it comes to food safety standards and regulations, especially in the informal market segment.

This is despite having progressive regulations that seek to improve the efficiency and safety of dairy products along the supply chain.

Last week, at an informal open-air milk market, I observed two buyers and a hawker. One buyer touched the notably clean food-grade container and commented, “tununue hii, ndio imekamuliwa saa hii”.

My conversation with the hawker revealed that the milk was warm, suggesting it had just been harvested from the cow and that is what customers prefer alongside a lower cost.

This raises concern over consumer purchasing decisions regarding pasteurised versus un-chilled raw fluid milk and knowledge on raw fluid milk health risks, particularly in the rural and urban informal settlements.

The Kenya Dairy Master Plan in line with Vision 2030 outlines the strategies to shift a larger proportion of marketed milk from informal trading to formal sale of pasteurised milk.

Additionally, the recent draft Dairy Industry (Dairy Produce Safety) Regulations also advocates against fluid milk hawking to consumers.

This move is mainly to enhance consumer health protection through hygienic milk handling and safety practices from farm to (formal) markets. In the formal markets, milk quality tests and consequent rejection when necessary offer consumers distinct quality advantages.

A study carried out last year in Nyandarua, Nakuru and Laikipia counties shows that some farmers do not discard milk from sick and treated animals, which explains why there is increased antibiotic residues above the required limit in milk largely obtained from the informal market.

The antibiotic residue risks together with pre-and post-harvest milk handling practices greatly influence contamination and subsequently milk quality and safety.

Second, whether the consumer will chill or boil the milk immediately, milk quality issues and potential health risks associated with consuming (un-chilled) raw milk cannot be overlooked.

Another research investigated raw milk samples collected from the same farm; where group one samples had milk chilled immediately to 4°C immediately after milking while group two samples were held at room temperature for about two hours followed by rapid chilling to 4 °C (delayed chilling) – a common practice where consumers buy ‘warm’ milk then chill or refrigerate at home.

The findings showed that delayed chilling of raw milk leads to several undesirable chemical changes compared to immediate chilling. This shows that the quicker milk is cooled after milking, the better the quality.

Milk gets easily contaminated with dirt, harmful bacteria and odours and is also an excellent medium for bacterial growth particularly when not properly cooled and handled. The local regulations further state that a dairy business operator should ensure all (processed) dairy produce is cooled immediately prior to dispensing, to a temperature preferably below 4°C up to about 7°C.

Cooling milk immediately after milking helps keep bacteria from multiplying rapidly and preserves its quality. It is atypical of smallholder dairy farmers to cool milk on the farm before sale, but the emphasis to the consumer is that warm milk does not necessarily depict time lapse from milking, neither is it a measure of its safety or quality.

Raw milk harbours a variety of micro-organisms that can be sources of foodborne pathogens; derived from several areas including the interior of the udder, exterior surfaces of the animals, environment, milk-handling equipment and personnel. Prevalent pathogens include Campylobacter jejuni, E. coli (O157:H7), Listeria monocytogenes, Brucella spp and Salmonella spp.

Most outbreaks of illnesses have been traced to foodborne pathogens associated with the consumption of non-pasteurised milk, not properly pasteurised and sometimes pasteurised milk – potentially due to re-contamination. Whereas pasteurisation alone is not the final solution to controlling milk-borne pathogens, raw milk is still recognised as a major cause of diseases.

In summary, consumer purchasing decisions based on low cost and other incentives rather than quality stifle the growth of formal milk supply chain. Consumers should also get attracted to milk retailers that adopt innovations that assures quality and safety of marketed milk.

The writer is based at AgriDairy Innovations,