Learn the science behind:
Where Milk Comes from – Visting a Dairy Farm
Almost all of our food starts at a farm where plants are grown, animals are raised or fish are kept. Here’s where farmers use photosynthesis and biology to convert sunlight into high quality foods. It’s where grass is transformed into milk, thanks to a machine called ‘cow’ (or goat, …). It’s pretty amazing how nature has developed to enable such complex processes.
Milk again is the starting point for so many other products. Here’s where we humans use technology, whether it’s advanced or not, to continue transforming. Ice cream, buttermilk, yogurt, cream, creme fraiche, they all start out with milk.
Farming is often depicted with idyllic photos of pastures whereas there’s also a ton of technology involved nowadays. We believe that truly understanding where your ingredients come from and how they work will make you a better scientist.
Food science starts in the farm, not the factory!
Visiting a farm
When visiting the maple syrup farm in Michigan we decided to also drive by a dairy farm not too far out. Since it was still winter, there weren’t a lot of farms open to the public yet and also at the farm we visited it was quite calm. Nevertheless, we were welcomed very warmly and despite the fact that there were only two of us, got a complete tour of the farm!
We entered the barn on a viewing deck, one level above the cows. From here we could see cows relaxing, ruminating, eating and walking around. It was very calm, no flies, no noise, no cows mooing. Designing these kinds of barns takes a lot of thought. The amount of air circulation, ventilation, temperature control (there’s no heating but it still stays considerably warm during winter, cows’ optimal temperatures are below those of humans) as well as the flooring materials, all have been thought through extensively.
By no means am I an agricultural expert so we relied heavily on what the farmer explained to us for this article. There is a ton of research on dairy farming out there which looks into a lot of these aspects in even more detail.
After having observed the cows from above for a while we head downstairs, to the same level as the cows are at. Here is where the milking robots are located. Milk robots are literally exactly what the name says they are, they are fully automated robots that can milk every cow.
A cow walks inside the robot and gets scanned on their tag. The machine then knows which cow has just entered and using lasers is able to attach all four milk robot arms onto the cow’s udders, but not before disinfecting the udders themselves. While this happens, the cow couldn’t be standing more calmly inside the robot. Of course, she knows she’ll be getting feed as well. This feed, which all the cows seem to love, is dosed in the right quantity for each cow and depends, amongst others, on the amount of milk she’s producing.
Once milking is completed the cow calmly leaves the robot, back to the barn to relax, ruminate or eat. Some cows try going back into the robot almost immediately, hoping for some more food. Unfortunately for them, the robot recognizes them and they are gently pushed out again.
The farmer tells us that each cow has her own milking rhythm and they tend to go back to the robot at set time intervals, knowing when it’s time for milking again. Since they can roughly decide on their own schedule, yields are better and cows are happier. Cows that produce a lot of milk may be milked more often, than cows producing less, which is better for all.
Here’s a difference to a lot of sheep/mutton farming practices out there. They often don’t use the milk robots.
Milk enters technology
Without anyone having so much as seen the milk it is transported from the cow into storage tanks immediately. The equipment does a few checks and the milk goes into a system of tubing to be cooled down immediately.
Milk is the temperature of the cow’s body when it leaves the cow, but should be brought down to below several degrees (Celsius) above zero quite quickly. This way, micro organisms don’t have a chance to grow and the milk doesn’t spoil. After the heat exchangers which cool the milk quickly, it enters the stainless steel tank, ready for pick up by their distributor.
Milk leaves the farm
Once every two days milk is picked up at the farm we visited. The milk robots are closed for cows at this point, they’ll have to wait a little while. The transporter pumps the storage tank empty and sanitizes the whole system, this to avoid that a possibly contaminated batch can also infect the next one. Once the tank has been emptied and cleaned, the milk robots open for business again. Starting yet another cycle of milking.