The common method of separating cream out of whole milk hasn’t changed in a century or so. It’s basically centrifuging the mixture, the heavier milk gets flung out to the edge and the lighter cream stays in the center. If you get unhomogenized milk you can just leave it in the fridge and the cream will rise to the top for you to carefully skim off – this low tech simple way was used by all for centuries prior to centrifuge cream separators – and still a method I like. Our cream separator from the 1930’s is all mechanical and though you could attach it to the power take off of a tractor we just hand crank. It has about 40 parts, mainly due to the stack of 30 cone-shaped discs which are part of the spinning apparatus. I took pictures of the assembly when we were taught it a few weeks ago so I would be able to put it together myself next time. We separated 27 pounds of milk (about 3 gallons), which is one days worth from April, our 100% Jersey cow. She gives very high butterfat milk and we got about two quarts of cream that day.
Here she is eating while I milk her.
Now for the assembly of the cream separator:
The cream comes out the top spout and the skimmed milk out the bottom. You can send the skimmed milk though again to get a second run of lighter cream. So far I have made butter a few times, cultured creme fraiche, whipped cream and plan to make panacotta soon.
Here is a video of the cream separator:
Our cows have been getting hormone shots so that they can be breed on July 1st – the shots are to sync their cycles so the breeding can be done all on the same day (I know, seems like a less than perfect method and I’d like to see how Amish or no chemical farms cope with this). Sadly for them they don’t get to do it the old-fashioned way since Jersey bulls are very bad-tempered and cannot be kept on the farm. One benefit I guess is that they can sex select the sperm so they get female calves. With the cows being given synthetic hormones I do not want to use the milk so I haven’t been collecting or using the it for these 10 days. This is different from the recombinant bovine growth hormone (rBGH) but still not natural. Our manager feels the milk is fine and even took some home to make ice cream today so I’m thinking that other dairies use/sell the milk while the hormones are being given which is worrisome and something I’ll ask my milk farmers when I’m back home buying milk. In the meantime we’ve been trying milk baths and tossing lots of milk. I miss the fresh milk and cream and the break has made me realize that I need to make a lot of butter and freeze it or make it into ghee once the hormones are gone. I also made my first hard cheese 2 weeks ago, it’s a fast one so I tasted it recently and other than being too salty due to an error on my part it’s pretty good, my family even eats it!