Milk, Buttermilk, Fluid, Cultured, Lowfat: How Many Grams in a Cup?
Cultured lowfat buttermilk — the commercial version widely sold in cartons — is produced by fermenting lowfat milk (typically 1–2% fat) with lactic acid bacteria. Despite the name, it contains no butter and is thinner than sour cream or plain yogurt. At 1.036 g/ml, it is marginally denser than whole milk (1.031 g/ml) because the lower fat content leaves more dissolved water-soluble solids per unit volume. A cup weighs approximately 245 g; a tablespoon weighs about 15.3 g. Pourable like regular milk, with a tangy flavor. Its most important culinary role is its acidity: it reacts with baking soda to leaven biscuits, pancakes, cakes, and fried chicken coatings.
Quick convert
- US cup = 236.588 mL
- 1 tbsp = 14.787 mL
- 1 tsp = 4.929 mL
Reference table
| Cups | g |
|---|---|
| 0.3 | 61 |
| 0.5 | 123 |
| 0.8 | 184 |
| 1.0 | 245 |
| 1.5 | 368 |
| 2.0 | 490 |
FAQ
- Why is buttermilk slightly denser than whole milk?
- Commercial lowfat buttermilk (1.036 g/ml) is denser than whole milk (1.031 g/ml) because it has less fat — and fat, at ~0.9 g/ml, is less dense than water. With less fat in the mixture, the remaining water-soluble milk solids push the overall density slightly higher. The difference is only about 1 g per cup — negligible for cooking.
- Can I substitute regular milk for buttermilk by weight in baking?
- By weight, the densities are close enough (1.036 vs 1.031 g/ml, <1% difference) that volume and gram substitutions are structurally equivalent. However, buttermilk's acidity is what triggers leavening when paired with baking soda. A functional substitute is 1 cup milk + 1 tablespoon lemon juice or vinegar, left to curdle — this replicates the acidity but not the protein composition.
- How many grams is a cup of buttermilk?
- At 1.036 g/ml, one cup (236.6 ml) of lowfat cultured buttermilk weighs approximately 245 g — the same as skim milk and about 1 g more than whole milk.