Best Buttermilk Substitutes (With Ratios)
The best buttermilk substitute is soured milk: put 1 Tbsp (15 mL) lemon juice or white vinegar in a measuring cup, top it up to 1 cup (250 mL) with milk, and let it stand 5–10 minutes. Use it in exactly the same amount as the buttermilk in your recipe.
Buttermilk substitutes and ratios
| Substitute | Amount per 1 cup buttermilk | Best for | Why it works |
|---|---|---|---|
| Milk + lemon juice or vinegar | 1 Tbsp acid + milk to 1 cup | Pancakes, biscuits, cakes | Acid curdles milk protein and matches buttermilk's tang |
| Plain yogurt + milk | 3/4 cup yogurt + 1/4 cup milk | Biscuits, scones, marinades | Already cultured with lactic acid, so flavour is closest |
| Kefir | 1 cup | Anything, including dressings | A cultured milk with similar acidity and pourable body |
| Sour cream + water | 3/4 cup sour cream + 1/4 cup water | Cakes, quick breads | Cultured and acidic; extra fat makes a richer crumb |
| Milk + cream of tartar | 1 3/4 tsp cream of tartar + 1 cup milk | Baking when you have no citrus | A dry acid; whisk it into a little milk first so it doesn't clump |
| Buttermilk powder | 4 Tbsp powder + 1 cup water | Regular baking | Dehydrated real buttermilk |
| Soy milk + lemon juice | 1 Tbsp lemon + soy milk to 1 cup | Dairy-free baking | Soy protein thickens with acid like casein |
Why the swap works
Cultured buttermilk has a pH of about 4.4–4.8, thanks to lactic acid made by bacteria. That acidity does three jobs in baking:
- It powers baking soda. Acid reacts with baking soda (sodium bicarbonate) to release carbon dioxide. One cup of buttermilk neutralizes roughly 1/2 tsp baking soda, which is why so many buttermilk recipes use that amount.
- It tenderizes. Lower pH weakens gluten, so pancakes and cakes come out soft instead of chewy.
- It thickens. Acid makes milk's casein proteins clump, giving body that helps batter hold air bubbles.
Lemon juice and vinegar recreate the acid. Yogurt and kefir go further by also bringing the cultured flavour, which is why they taste most like the real thing.
Chef Fizz says: Don't worry when your soured milk looks lumpy. Those curds are casein doing its job, and they vanish into the batter.
When not to swap
- Raw uses like ranch dressing or cold soups. Soured milk tastes sharp and thin. Use kefir or thinned yogurt instead.
- Recipes built for low-fat buttermilk with lots of baking soda. Sour cream adds fat that can make delicate cakes heavy; stick to soured milk.
- Long buttermilk brines for fried chicken. Soured milk works, but yogurt or kefir clings better and tenderizes more gently over 12–24 hours.
- Ultra-high-temperature (UHT) or very low-fat milk. It curdles weakly, so the substitute stays thin. Use 2% or whole milk if you can.
Questions
How long does homemade buttermilk need to sit?
About 5 to 10 minutes at room temperature. It will thicken slightly and look a little curdled, which is exactly what you want.
Can I use yogurt instead of buttermilk?
Yes. Thin 3/4 cup plain yogurt with 1/4 cup milk or water to replace 1 cup buttermilk. The flavour and acidity are very close, and it works in pancakes, biscuits and marinades.
Does soured milk work in recipes with baking soda?
Yes. The lemon juice or vinegar supplies the acid that baking soda needs to release carbon dioxide, so the rise is very similar to real buttermilk.
What is a dairy-free buttermilk substitute?
Unsweetened soy milk with 1 Tbsp lemon juice per cup works best, because soy's protein thickens with acid much like dairy does. Almond and oat milk sour but stay thin.