Eight cultured dairy foods, side by side

A bowl of skyr, a glass of kefir and a spoonful of sour cream all belong in the cultured dairy conversation. To choose between them, look at three things: the starting ingredient, the culture and what happens after fermentation.

Skyr

Culturing and concentration produce a dense bowl. Skimmed milk is a common starting point, but makers choose their own ingredients and cultures. Treat the name as an invitation to look at the method, rather than a guarantee of one fixed formula. Ísey Skyr: Our skyr

Read our full introduction to skyr for the process and three serving ideas.

Yogurt

In yogurt, bacterial cultures produce acidity and help the milk form a gel. It may be left set or stirred. Straining is an additional choice, rather than a required step in every yogurt method. University of Illinois Extension: Making yogurt at home

Read our yogurt introduction, then try a plain spoonful before adding fruit. For a first batch, follow the complete heating, cooling, incubation and refrigeration instructions in the linked university guide.

Milk kefir

Milk kefir brings bacteria and yeasts together. Traditional kefir grains are a culture community, not cereal grains. Its usual pourable texture gives it a different place at breakfast from thick skyr. Water kefir is a separate project with a different starting liquid and culture. FAO/WHO Codex: Standard for fermented milks

Pour into a glass or use finished milk kefir in a smoothie. Follow instructions for your actual kefir culture; a yogurt starter is not an interchangeable substitute.

Labneh

Labneh starts with yogurt and becomes thicker as whey drains away. It is a useful way to explore how removing moisture changes a food you already know. The Washington State University method strains yogurt in the refrigerator and notes that added stabilizers can hinder separation. Washington State University Extension: Yogurt made simple

Spread finished labneh on toast with herbs and olive oil. If making it, use the full linked method, including its covered refrigerated draining step.

Quark

Quark belongs to the family of soft, acid-coagulated fresh cheeses. Milk forms a curd and whey is separated. It may resemble a thick yogurt in the bowl, but its cheese-making method and culture choice deserve their own instructions. University of Guelph: Cultured dairy products and cheese

Try finished quark as an herb spread or in a recipe written for quark. Thickness and moisture matter in baking, so avoid assuming that every soft dairy food swaps one-for-one.

Sour cream

For cultured sour cream, cream is the starting point. Bacterial fermentation develops acidity in a richer base than ordinary milk. Fat content and formulation vary, so two pots can behave differently even when both are called sour cream. University of Guelph: Cultured dairy products and cheese

Use a spoonful as a topping for potatoes or a finished soup. When baking or cooking a sauce, follow the recipe's specified dairy product rather than choosing by appearance alone.

Tvorog

Fresh cultured curds offer another texture. Whey separation and handling shape the finished cheese. Tetra Pak Dairy Processing Handbook: Cheese Read our introduction to tvorog for serving ideas and a comparison with other soft dairy foods.

Ryazhenka

The milk is baked before culturing, creating a different starting point from ordinary milk yogurt. Slovyanochka: Ryazhenka made from baked milk Meet ryazhenka and explore it alongside the other foods in this collection.

Choose the food, then the method

For a dense bowl, explore skyr. For a drink, look at milk kefir. For a spread, compare labneh and quark. For a rich topping, look at cultured sour cream. These are suggestions about eating and texture, not a ranking of health benefits.

When you are ready to make a batch, use a complete method for that food and its starter. Our cultured dairy section keeps the eight starting points together.