- Calories: 152 -> 146
- Protein: 8.14 g -> 8 g
- Carbs: 12 g -> 11.4 g
- Calcium: 28% DV -> 23% DV
- Vitamin D: 24% DV -> 13% DV
- Vitamin B12: 18% DV -> 13% DV
- Phosphorus: 22% DV -> 20% DV
Unless you remove the skim, it's difficult to imagine that some parts just disappear.
> - Calories: 152 -> 146
Dubious: But it's easier to discuss proteins and carbs separately.
> - Protein: 8.14 g -> 8 g
Possible?: Some proteins may denaturalize (like the white of the egg), but they are sill there. Proteins are weird, so I can't say it's impossible.
> - Carbs: 12 g -> 11.4 g
Dubious: Unless you are overheating the milk to make caramel, this is very strange, almost impossible. Carbs are composed of smaller sugar units and with heat they may split or for new bound, but they don't disappear unless it's very hot.
> - Calcium: 28% DV -> 23% DV
Impossible: I don't expect calcium to react with the container or to evaporate, so it's impossible that it goes away. The biological availability may change, but it's difficult to measure.
> - Vitamin D: 24% DV -> 13% DV
Possible: Some vitamins are sensible to heating, and heating them changes the molecular structure to make then unusable, so this is totally possible. I don't remember about vitamin D in particular. Anyway, many commercial milk has additional vitamin A and D.
> - Vitamin B12: 18% DV -> 13% DV
Possible: Idem. Anyway, I but I never heard of milk with additional B12, and other foods are better sources of B12.
- Phosphorus: 22% DV -> 20% DV
Dubious: I don't expect potassium to evaporate. It may react with the container, but I doubt it. The biological availability may change a lot, because phosphorus is used to bind some molecules and they may split and the isolated phosphate may not be as useful.
In principle boiling could induce a lot of evaporation, so the milk would be more concentrated, and so it would have more calories per cup. But people don’t boil the milk so much as to materially reduce the amount of water in it.
Today, calorie counts are usually obtained by checking the protein, fat, sugar and fiber contents, and using known values for calorie/g of each. Those well-known values are ideally obtained either through human calorimetric studies, or through burning protein, fat, sugar directly.
What does that mean?
Pasteurization involves heating but doesn't require boiling. You can pasteurize by heating to 73 degrees C for 25 seconds.
Boiling, in the case of milk, is heating it to its boiling point which is around 100.17 degrees C.
Boiling has a higher impact in the nutritional value of milk than pasteurization.