Gräddfil

Gräddfil is Swedish sour cream. It is cream fermented with lactic acid bacteria until thick, spoonable and tangy. It usually has about 12 percent fat, a little less than American sour cream and much less than crème fraîche. It tastes fresh, sour and mild.

How to use it

Swedes use gräddfil cold:

• Dips. Stir in chopped dill, chives, garlic or a spice mix, salt and pepper. Serve with chips, raw vegetables or baked potatoes.
• With fish. Mix with dill, lemon and horseradish to go with salmon, herring or crayfish.
• Toppings. Spoon on baked potatoes, potato pancakes or blinis with fish roe.
• Baking. Use it in cakes and quick breads for moisture and tang.

It is common on the Swedish smörgåsbord and in the sauces served with new potatoes at midsummer.

Substitutes

Outside Scandinavia, use:

• Sour cream, the closest swap. Use the same amount. Light sour cream is nearer in fat.
• Plain Greek yogurt mixed with a little cream, about 4 parts yogurt to 1 part cream, for a similar thickness and tang.
• Crème fraîche, which is richer and less sour. Add a squeeze of lemon if you want more tang.

How to store it

Keep it in the fridge and use it within about a week of opening. Pour off any liquid on top or stir it back in. Throw it out if it has mold, smells off or tastes bitter.

Common mistakes

• Boiling it. With only about 12 percent fat, gräddfil curdles in hot sauces. Stir it in off the heat, or use crème fraîche for cooking.
• Whisking it hard. It gets runny. Stir gently.

In recipes

Swedish recipes use gräddfil where English recipes use sour cream. "Gräddfilssås" means a cold sour cream sauce, usually with herbs. It is often paired with dill, from fresh fronds to krondill. Do not confuse it with filmjölk, which is a thin, drinkable cultured milk.