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Cream of tartar:
grams to cups.
Cream of tartar (potassium bitartrate) weighs 150 g per cup, but like baking powder and baking soda, it's almost exclusively measured in teaspoons. A teaspoon weighs about 3.1 g — a small enough quantity that a kitchen scale with 1 g resolution is the minimum needed for accurate weighing.
Cream of Tartar: grams to cups
Approximate cup fractions for common gram amounts. Based on 150 g per cup.
| Grams | Cups (approx) | Decimal |
|---|---|---|
| 25 g | ⅙ | 0.17 |
| 50 g | ⅓ | 0.33 |
| 100 g | ⅔ | 0.67 |
| 150 g | 1 | 1.00 |
| 200 g | 1 ⅓ | 1.33 |
| 250 g | 1 ⅔ | 1.67 |
| 500 g | 3 ⅓ | 3.33 |
Cream of Tartar: cups to grams
Based on 150 g per cup.
| Volume | Grams (g) |
|---|---|
| 1 cup | 150 g |
| ¾ cup | 113 g |
| ½ cup | 75 g |
| ⅓ cup | 50 g |
| ¼ cup | 38 g |
| 1 tbsp | 9 g |
| 1 tsp | 3 g |
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What cream of tartar does and why small measurement errors matter
Cream of tartar is an acidic byproduct of winemaking, used in baking for three distinct purposes: stabilizing whipped egg whites (prevents them from deflating), preventing sugar crystallization in candies and syrups, and as the acid component in homemade baking powder (mixed with baking soda). In meringues and angel food cake, cream of tartar makes the foam more stable and fine-grained. A typical recipe uses ¼–½ teaspoon for a batch of 4 egg whites. Over-adding produces a slightly tart flavor and can over-acidify the whites, while under-adding leaves the foam less stable. At 3.1 g per teaspoon, these small quantities are at the edge of what a 1 g-resolution scale can measure reliably.
Cream of tartar in candy-making and its anti-crystallization role
In candy-making, cream of tartar is added to sugar syrups to prevent graininess. Sugar is prone to crystallizing as it cools — a single seed crystal can trigger a chain reaction that turns a smooth syrup into a grainy, gritty mass. Cream of tartar's acidity partially inverts the sucrose (splitting it into fructose and glucose), which prevents crystals from forming. Even a small amount — ¼ teaspoon per cup of sugar — is enough to inhibit crystallization. This is an application where exact quantity matters: too little doesn't prevent crystallization, too much adds noticeable tartness to the candy.
Frequently asked questions
- How many grams is 1 teaspoon of cream of tartar?
- 1 teaspoon of cream of tartar weighs about 3.1 g (150 g ÷ 48 teaspoons per cup).
- How many grams is ½ teaspoon of cream of tartar?
- ½ teaspoon of cream of tartar weighs about 1.5–1.6 g.
- What can I substitute for cream of tartar?
- For stabilizing egg whites, a small amount of lemon juice (¼ tsp per egg white) works as a substitute. For baking powder: mix 1 tsp cream of tartar with ½ tsp baking soda to replace 1½ tsp baking powder.
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