How to skim your own milk

[sibyloftherhine]

Does anyone have experience skimming their own milk (separating into cream and milk)? All the low fat milk in my country contains synthetic vitamin A and vitamin D, and all the cream has carrageenan or soy lecithin, but full cream milk is available without additives.

I've done some research into how to skim milk. Some sources say that transferring it into a container then chilling it in the refrigerator for 24 hours will be sufficient for it to separate, others say heating is necessary, while others say a milk separator is necessary. Does anyone have advice on what would probably work best? Thank you!

 

[schultz]

If it's not homogenized it can be left in the fridge for a day or two and then separated (if it's cow's milk). A quicker, more expensive way is a separator. A separator probably skims it to a lower % than hand skimming it. It may depend on the brand of separator.

Either way is fine. You don't have to heat it.

 

[rr1]

Yeah agree with the above, letting it sit and scraping the fat off the top is very easy (for unhomogenized milk of course). Sometimes the fat will not go to the top, but if you rapidly shake the milk and let it sit a couple more days, it will separate. I'm not really sure why, but it works.

 

[PolishSun]

fat tends to go up on liquids.

 

[sibyloftherhine]

If it's not homogenized it can be left in the fridge for a day or two and then separated (if it's cow's milk). A quicker, more expensive way is a separator. A separator probably skims it to a lower % than hand skimming it. It may depend on the brand of separator.

Either way is fine. You don't have to heat it.

I'll try this today and update this thread in the coming days. Thanks for the tips!

 

[Vajra]

If it's not homogenized it can be left in the fridge for a day or two and then separated (if it's cow's milk)

Yeah agree with the above, letting it sit and scraping the fat off the top is very easy (for unhomogenized milk of course). Sometimes the fat will not go to the top, but if you rapidly shake the milk and let it sit a couple more days, it will separate. I'm not really sure why, but it works.

How much % fat do you reckon is removed in your experience?

 

[schultz]

How much % fat do you reckon is removed in your experience?

I'm just guessing, but I would think it would land somewhere around 0.5%? I'm kind of curious now, so maybe I'll try to look that up...

Edit: It might even depend on the cow breed... and obviously how long it's left to sit.

Edit 2: I did find a study discussing gravity separation of milk in regards to making parmesan cheese. There seems to be a difference in fat globule size in gravity separated milk vs centrifuge. I'm not exactly sure what affect this has on the cheese flavour profile, but they did mention the bacteria content might change (it floats to the top with the cream to some degree?) and they mentioned several reasons why they think it would make a uniquely flavoured cheese (as in traditional parmesan). I didn't read the whole study, and was just scanning.

It says this... "A 2% fat milk can also be obtained by gravity separating raw milk at 4°C for 24 h and then draining the bottom 91.7% of the total volume."

I thought you might be able to get to 0.5% after like 5 days, but maybe that's unlikely? 2% is used for making parmesan I think so I don't think they were trying for any lower. They do mention that in the very bottom of the milk, the "skim layer", it was 0.2% fat. That was only the bottom 8.3% though. So they define 3 different layers: skim, partial and cream layers.

Another quote.... "After 48 h at 4°C, the percentage of fat in the bottom 8.3% of the milk volume (skim layer, F1) decreased to 0.2%, whereas that of cream layer (F7) increased to 26.6%, achieving a creaming capacity of 58.8%. Milk for cheese making of 2% fat obtained by gravity separation has a smaller fat globule size VMD than that prepared by centrifugation. Gravity separation at 4°C for 48 h can yield skim milk (0.2% fat), lowfat milks (1 and 2% fat), and cream (containing about 25 to 27% fat)."

Article Link

 

[Tomb.]

I regularly skim my own raw milk. 24hrs in a cold fridge is usually enough to separate it, I do two passes and that gets the vast majority of the fat out of it.

Makes the best butter around.

 

[Vajra]

I'm just guessing, but I would think it would land somewhere around 0.5%? I'm kind of curious now, so maybe I'll try to look that up...

Edit: It might even depend on the cow breed... and obviously how long it's left to sit.

-0.5% or from ~3-5% etc. to 0.5?