What it will take to produce 'clean milk'

Dear Daktari,

Thank you for your informative articles to us farmers. I’m a dairy farmer from Bomet County. I would wish you to enlighten us on what it takes to produce clean milk. I’m asking this because recently, a farmer friend told me he sought to deliver his milk to a dairy cooperative and was informed that they only accept “clean milk.” I thought this was rather ambiguous. In your view, what constitutes “clean milk,” and how does a farmer achieve the same?

Joseph Ruto,

Bomet County

Thank you so much, Joseph, for reading Smart Harvest and for your question on what it takes to produce clean milk. 

Many factors contribute to the quality of milk being termed as “clean.” These factors are interrelated as they are sequential—probably like a chain concept, with the strength being determined by the weakest link.  

It must be noted that milk is a very perishable commodity; it is easily contaminated and can pick up any strong smell in the environment or from the person handling it.

Milk is an excellent medium for bacterial growth, a reason it so easily gets spoilt or contaminated and hence is a public health risk. Here are a few factors that determine the quality of milk.

Feeds: Milk is derived from the feeds given to animals. The cow should be fed on quality and clean feeds, free from any contamination. It should not be fed on feeds, pastures, or weeds that may cause milk tainting - imparting a foul odour into milk. In addition to the feeds, ensure a lactating cow gets enough water at all times. Quality feeds at milking also play a role in stimulating milk letdown.

The cow: The cow from which milk will be gotten should be in good health. Many diseases can be passed through milk handling and the consumption of raw milk. Of great importance is the udder’s health. The udder should be free from mastitis. Make sure the withdrawal period is observed if you are milking a cow that has been initially sick and under antimicrobial treatment. This will ensure that the milk is free from antimicrobials, which, when consumed through milk, contribute to the development of antimicrobial resistance. Every drug has a withdrawal period from the manufacturer written on the package.

Where milking is done: The extraction of milk should be done in a clean environment. The milk parlour should be kept clean. It should preferably have a cement floor for ease of cleaning. Where there are large herds, use a movable parlour to reduce contamination. The milking place should be cleaned after every milking. Cleanliness minimises foul smell and also helps keep away flies that can be a nuisance to the cow and even disease vectors.

Milking collection and storage equipment: Aluminium and stainless steel are preferred for handling and storing milk. This is because they are easy to clean. They should be washed thoroughly and dried after use. Avoid plastic jerricans, as they can’t be thoroughly washed, and this normally alters the original milk smell.

The milker and the milking: The person doing the milking should be healthy and clean. If hand milking, the hands should be washed thoroughly and nails maintained short.

They should not smoke while milking, as the smell can easily be transferred to the milk. For optimal milk expression, the milking should be quickly done without any interruptions while the animal is being fed quality feeds and is not under any stress. Routinely check for mastitis with a strip cup before milking.

Hand milking should be done by gentle but firm teat squeezing and not pulling.

Consumption of raw milk can cause zoonotic infections in humans. Milk for home consumption should be boiled.

[Dr Othieno is a veterinary surgeon and the current head of communications at the Food and Agriculture Organisation (FAO) Kenya. The views expressed here are not necessarily FAO’s but his own]