Sour cream in grams, and the tub that gains weight by losing fat
Full-fat sour cream weighs 230 grams to the US cup. The reduced-fat tub standing beside it in the chiller weighs 242, twelve grams more from the same cup. Buying the lighter product hands you the heavier measure, and the reason is sitting in your own kitchen.
The light tub weighs more
The USDA weighs full-fat cultured sour cream at 230 g a cup and the reduced-fat version at 242 g. Nothing about that is a mistake. Fat is the lightest ingredient in the tub: our olive oil page puts fat at 0.91 grams a millilitre against water's 1.00. Skim fat out of sour cream and water takes the space it left, so the cup gets heavier as the product gets leaner. A recipe written in cups will not notice. A recipe written in grams will, and the swap costs you twelve grams a cup in the opposite direction to the one the label suggests.
Sour cream conversions in full
Full-fat figures, following the USDA's 230 gram cup. A whole cup of sour cream in grams is the common lookup; the tablespoon is the USDA's own published figure rather than a sixteenth of the cup.
| Sour cream (full fat) | Grams | Ounces |
|---|---|---|
| 1 tablespoon | 12 g | 0.42 oz |
| 1/4 cup | 57.5 g | 2 oz |
| 1/3 cup | 76.7 g | 2.7 oz |
| 1/2 cup | 115 g | 4.1 oz |
| 3/4 cup | 173 g | 6.1 oz |
| 1 cup | 230 g | 8.1 oz |
| 2 cups | 460 g | 16.2 oz |
Density used: 0.97 g per ml, a shade under water at 1.00.
Three grams, and the eight-ounce fingerprint
The two American authorities sit 3 grams apart here, the closest they come on any dairy row. King Arthur reads 227, the USDA 230. That 227 deserves a second look: it is exactly 8 avoirdupois ounces, and it is the third dairy row where King Arthur lands on that same number. Milk 227, yogurt 227, sour cream 227. Three different products cannot all weigh 8 ounces to the cup; what they share is a rule, not a scale. We publish the USDA's 230 g, and the methodology page sets out how we tell an applied rule from a reading.
| Authority | A US cup, full fat |
|---|---|
| King Arthur Baking ingredient weight chart | 227 g |
| USDA FoodData Central | 230 g |
Sour cream abroad
Both New Zealand authorities, Edmonds and Chelsea, weigh a 250 millilitre cup at 250 g, while Australian Women's Weekly reads 240. Kyoritsu weighs a 200 millilitre Japanese cup at 160 g and is the only Japanese table that carries sour cream at all, so that figure stands alone rather than being confirmed by a second reading.
| Cup | Sour cream |
|---|---|
| US customary | 230 g |
| Metric (250 ml) | 240 to 250 g |
| Japanese (200 ml) | 160 g |
Questions about sour cream weight
- How many grams is a cup of sour cream?
- 230 g for full-fat, from the USDA. Reduced-fat sour cream is heavier at 242 g a cup, because the fat that came out was replaced by water, and water outweighs fat.
- Why is the reduced-fat tub heavier?
- Fat is the lightest thing in the tub. Our olive oil page reads 0.91 g per millilitre against water's 1.00, so taking fat out and letting water fill the space makes the same cup weigh more. The diet version is denser, not larger.
- How much does a tablespoon of sour cream weigh?
- 12 g, from the USDA. Sour cream holds its shape on a spoon, so a level tablespoon is a real measure here rather than an approximation, provided you scrape it flat.
Slavic recipes name sour cream by fat percentage rather than one product, which Eastern European measurements sets in context alongside the faceted glass.
Sources
USDA FoodData Central SR Legacy for the 230 gram full-fat cup, the 242 gram reduced-fat cup and the 12 gram tablespoon. King Arthur Baking for the 227 gram cup. Edmonds, Chelsea and Australian Women's Weekly for the metric cup. Kyoritsu Foods for the 160 gram Japanese cup. Full citations on the sources page.