Skim milk + 2% = 1% ?

July 14, 2010 2:23 PM

If you were to combine 1 cup of skim milk and 1 cup of 2% milk, does that essentially give you two cups of 1% milk?

This is all hypothetical, of course!

posted by ascetic to Science & Nature (17 answers total)

Sure, why not?

One cup skim + one cup cream = half and half?
posted by royalsong at 2:24 PM on July 14, 2010

Yes. Under the starting assumption that 1 cup of skim milk and 1 cup of 2% milk will yield 2 cups total,* the milkfat content of the mixture will be (1*0 + 1*0.02)/2 = 0.01, or 1%.

*This is an okay assumption in this case, but not always. E.g., 1 cup of water and 1 cup of ethanol will yield a final volume measurably less than 2 cups.
posted by AkzidenzGrotesk at 2:32 PM on July 14, 2010

Since the 1% milk will (likely) be homogenized, I wonder if they will mix well together. Probably OK for cooking or baking, but I don't think I would want to drink it.
posted by jeoc at 2:37 PM on July 14, 2010

Pretty close. Skim milk is not totally fat free (and the term "fat free" generally doesn't mean there is absolutely no fat in something), so you'll end up with something a little bit creamier than 1% milk.
posted by ssg at 2:38 PM on July 14, 2010

Skim milk is not totally fat free

True. I was making another assumption without realizing it! In the US, at least, skim milk can have fat content up to 0.5%. So the final mixture would be somewhere between 1% and 1.25%.
posted by AkzidenzGrotesk at 2:43 PM on July 14, 2010

That's approximately what the dairy does. When processing raw milk, they separate all of it into cream and skim milk. Then, when producing 1% they mix 1% cream back in. To produce 2%, they mix 2% cream back in.
posted by Chocolate Pickle at 2:44 PM on July 14, 2010 [1 favorite]

This is pretty much what Starbucks did when it first opened (I don't know what they're up to now, this may have changed). They stocked skim and homo, and mixed them in each drink to make what they called "2%".
posted by pseudostrabismus at 2:56 PM on July 14, 2010

And, in case you were curious, whole milk is between 3.5% and 4% fat.
posted by wisekaren at 2:57 PM on July 14, 2010

And, once again, I'd like to point out that milk has the fat content stripped-away once it reaches the factory. Then, fat is reintroduced to create the different grades.

And now you know.
posted by Thorzdad at 3:15 PM on July 14, 2010 [1 favorite]

I always wondered why ice cream recipes like this one required equal parts of cream and milk instead of just a whole part of half-and-half. I think I freaked my grandma out when I was 8 and I asked her this question and she didn't really know.
posted by thorny at 3:16 PM on July 14, 2010

thorny, it's because (in the US) the heavy whipping cream in that recipe is around 35% fat. Adding the same amount of (whole) milk gives you 19% fat. Half-and-half is only 12.5% fat.
posted by oneirodynia at 4:20 PM on July 14, 2010

thorny: "I always wondered why ice cream recipes like this one required equal parts of cream and milk instead of just a whole part of half-and-half. I think I freaked my grandma out when I was 8 and I asked her this question and she didn't really know."

Doesn't half-and-half from the big producers often have other chemical-y things in it now? Or maybe that is something called, like, "fat-free half-and-half" that I'm thinking of ...
posted by librarina at 4:21 PM on July 14, 2010

All sorts of people have posted substitution hacks for dairy products. This one from chowhound is pretty close to the best version I saw elsewhere (and which I can't find right now). This one from the Cook's Illustrated board is pretty good, too.
posted by maudlin at 4:41 PM on July 14, 2010

This is also what Starbucks does if you ask for 1% milk in Canada, where they stock skim, 2%, and homo (3.25%, or what Americans call whole milk).
posted by thisjax at 4:43 PM on July 14, 2010

The "fat free half and half" at my grocery is, if I remember right, skim milk and corn syrup.
posted by fantabulous timewaster at 6:44 PM on July 14, 2010

Sorry to answer a question with another question, but...

If 1c skim + 1c 2% = 2c ~1%
then
what does 1c water + 1c 2% milk equal?
posted by nineRED at 3:46 AM on July 15, 2010

That's watered down milk with half the fat, protein, milk sugars and general taste and flavour of a cup of 2%. It is not going to have the taste or flavour of 1%. This mixture could be useful in some kinds of baking (like Yorkshire pudding), but it's not going to taste like anything but watery milk when it's straight.
posted by maudlin at 6:23 AM on July 15, 2010