One of my tricks with homogenized milk is to start with a milk that has a low fat percentage, like a 1% or 2%, and then add the best commercial cream I can find to bring the fat content up to 3-4%. This has always set better for me than using regular whole milk.
This is an intriguing point. What is the explanation...in layman's terms, please. Wouldn't they be fairly equal as far as protein content? If that really is true, wouldn't we always want to use 1% or 2% and add cream to it, rather than use whole milk?
Yes, the composition by numbers is about the same. But the treatment of the fats often differs. In whole milk, everything is pushed through the homogenizer, which both breaks up the fats and smashes them into caseins. When that smashing happens, the caseins adsorb the fat molecules. Meaning you get proteins will little chunks of fats on their surfaces, making it more difficult for them to bond to each other to form a curd. So the curd is softer. In a low fat milk that's of good quality, the proteins are still there, but are less damaged (not always the case, depends on the process). So I like to use the milk that has decent proteins, and then use non-ultra-pasteurized, gently treated cream and add it back into the milk. It's much cheaper than raw milk, and while the results aren't as good, they're better than using regular whole milk.
Boofer, around here most of the 2% milk is no good. The good milk is in white plastic containers and has an expiration date that's about two weeks into the future, even when the milk is regularly restocked. Interestingly, the whole milk that's in white plastic containers, non-UP of course, is also quite decent. I've started using that more for ease to avoid the whole issue of adding cream. Trader Joes and Whole Foods both have good whole milk (again around here, not sure about other parts of the county), usually. Either the half gallon cartons or the gallon white plastic ones. It is a little Holstein-heavy and the curd set will be a little weak, but not terrible, pretty close to what raw Holstein milk is like.
For other parts of the country, it may be the same case or it may not. In general, the protein structure of lower fat milk is better, though. I wouldn't say it's always better, but I would say it's often the case, especially with cheaper milks.