Though milk and cream are sold by volume (gallons, liters, pints, milliliters), their fat content is given as a percentage based on weight. For instance, one gallon of 3.5% whole milk weighs about 3.904 kg. And since 0.035*3.904 kg = 0.1366 kg, a gallon of 3.5% milk contains 136.6 grams of milkfat (lipids).
Milk is mostly water, and besides fat it also contains proteins, carbohydrates, and vitamins and minerals. One gram of fat from milk provides about 8.93 calories (technically kilocalories), a figure that is usually rounded up to 9. The other calories in milk come from the proteins (about 4 kcal/g) and carbohydrates (about 4 kcal/g).
The least fatty type milk is skim, which must contain no more than 0.2% fat in order to bear the label of "skim" or "non-fat." Milk labeled "low-fat" contains no more than 1% fat, and milk labeled "reduced fat" contains no more than 2% milkfat. Whole milk, the fattest variety of milk, is generally between 3.25% and 3.7% fat.
Beyond whole milk are various kinds of cream such as half-and-half (50% whole milk and 50% cream), light table cream, and light and heavy whipping creams. Butter is made by removing the water from heavy cream and contains the highest concentration of milkfat at 81.1%.
The percentage of calories from fat is not the same as the milkfat percentage. For example, a 300 mL glass of 2% milk has about 155 calories, and 55 of those calories are from fat. The percent of calories from fat is 55/155 = 35%.
If you are curious about the number of calories and calories from fat in various milk products, you can use the calculator above, or look at the table below. See also the resources and references.
per 100 g
of 1 cup
per 1 cup
per 1 cup
|Fat Calories (kcal)|
per 1 cup
|Half & Half||11.5||242||27.8||314.6||248.5|
Making Milk/Cream SubstitutionsFor use as a beverage, nutritionists recommend that adults drink skim or low-fat milk rather than the fatter varieties, since milk contains saturated fats. Whole milk is more suitable for growing children whose bodies need the calories.
When using milk or cream in sauces and desserts, lower fat substitutions can affect the texture and consistency. For example, if a sauce recipe calls for whole milk, you can usually substitute 2% without causing a notable difference in taste and consistency, but if you use 1% or skim milk, the recipe will not turn out right.
Similarly, if a recipe requires heavy whipping cream, you may be able to use light whipping cream instead and still achieve the same result, but table cream or half-and-half will make the food too runny.
Some References for Milk Nutrition Facts:
USDA Nutrient Database
© Had2Know 2010