Q: I think that when a gallon of milk says 2 percent milk it means that there's 2 percent fat in there. My friend says it 2 percent of what we need in a day. Who's right? And if what's in the jug is 2 percent fat, what is that compared to? How much fat is in whole milk?
Answer: The numbers might seem to conflict, but they're really not so bad. First, you're right about the 2 percent; it means that 2 percent of the contents of the jug is cream or milk fat.
Your friend is confusing the 2 percent on the front with the numbers in the Nutrition Facts panel on the side of the carton. The numbers in the Nutrition Facts panel are based on a 2,000 calorie diet, so if that's how many calories you need, then the percentages there tell you how much you're getting of each individual nutrient toward your total daily need. Whole milk coming out of a cow is between 3 percent and 5 percent fat, and may be even more from some brands of dairy cattle. By law in Florida, milk sold as whole milk or just plain "milk," must be at least 3.25 percent fat. So 2 percent milk still has more than half the fat of whole milk. If milk is called "reduced fat," it has to have less than half, or less than 1.625 percent fat by law.
Florida Department of Agriculture and Consumer Services inspectors regularly check dairies, including milk being shipped in from other states, to be sure that what's on the label matches what's in the jug. The percentages can be within 0.3 percent, so 2 percent milk could have between 1.7 percent and 2.3 percent fat and still be legal. Skim milk has to have less than 0.2 percent fat.
These numbers might seem small, but remember that fat has 9 calories per gram, more than double the calories of milk sugar or protein.
Q: I have a recipe for Yorkshire puddings that specifies I should use only peanut oil. Why peanut oil? If I don't have that, is there any other oil I can use?
Answer: I don't know why it requires only peanut oil, although I suspect the intent was to be sure you're using an oil with a high smoke point. For Yorkshire puddings, the pan is usually heated first, then the hot batter is added and the pan returned to the oven. At high heat, olive oil, for instance, will start to smoke, turn dark and taste bitter. Peanut oil is a very mild tasting oil with a high smoke point. That means it can take the heat without burning or smoking.
However, there are other oils on the market that also have high smoke points. They might not be as mild in flavor, but if they are what you have on hand, they will work. Some of the more common oils with smoke points as high as peanut oil include refined corn oil, refined safflower and refined soybean oil. Refining makes a big difference in the smoke point. For example, unrefined soy oil smokes at 320 degrees, refined soy oil smokes at 460 degrees. Refined peanut and corn oil smoke at 450 degrees, while refined safflower oil goes to 510 degrees before smoking.
What you buy from the grocery shelf is all refined oil. On the low end, flax seed oil has a smoke point of 225 degrees and butter ranges from 250 to 300 degrees. All these differences are why only some oils are sold for use in turkey fryers. Those things get hot enough to cause some oils to smoke, too. Using the wrong oil would waste a good turkey!