Tarhana and related dried fermented soup bases

A fermented dough, dried into a soup base

Tarhana is a Turkish soup ingredient made by fermenting a dough of yoghurt and cereal, then drying it and rubbing it into small grains. The Ministry of Culture and Tourism describes it as generally made from yoghurt and cereals, or from yoghurt, cereals and vegetables, with aromatic herbs optional. The cereal can be wheat flour, semolina or both, and the usual vegetables are onions, tomatoes and fresh red peppers. A household cook who publishes her mother's method reckons there are more than a hundred kinds of tarhana, made with chickpeas, cranberries, tomatoes and other ingredients.

The finished product is dry, so it keeps and travels as a base for soup. Colour tells something of the recipe: the household author says orange comes from red pepper, and white from flour, which is increased when watery ingredients such as yoghurt and tomato are used.

The Ministry method

The Ministry's example starts with vegetables. Five onions, four tomatoes and five red peppers are cut into 3 cm cubes and cooked for 40 to 45 minutes in 400 g of salted boiling water, until very tender, then cooled and blended or sieved. A well is made in 880 g flour and 860 g semolina, and 1,100 g yoghurt and the vegetable purée go in. The dough is kneaded for 7 to 8 minutes, covered and left for 3 days at room temperature, being kneaded three times a day.

After that the dough is divided into egg-sized pieces on a clean cloth and dried in an airy, shaded place, kept slightly humid. Each piece is rubbed between the palms into small grains and dried again, then the grains are sieved and the drying repeated. The page does not give drying times, temperatures or how long the tarhana keeps, and it says the fermented mixture can alternatively be dried in a low-heat oven.

A longer household method

A separate household method makes a different tarhana and is not a variant of the Ministry quantities. It cooks 2 kg of red peppers until tender, adds chopped onions, two spoonfuls of plain yoghurt, 2 tablespoons of tarhana or 2 teaspoons of dry yeast, and 2 tablespoons of salt, and works in flour until the dough is elastic and no longer sticky. It ferments for ten days, with a handful of flour and 5 to 10 minutes of kneading each day. The pieces are then dried on a towel, cut smaller, ground finely in a food processor, dried for 2 to 3 more days, and stored in a glass jar.

The author gives rules of thumb: maximum sourness comes in 8 to 9 days, with 10 to 12 days ideal for a slightly sour, aromatic result, and tarhana kept about 21 days turns sweet rather than sour. A dough that has stopped rising has peaked. The author advises against drying in a hot oven because heat, she says, destroys the probiotics. That is her claim and the sources do not test it. No flour amount, fermentation temperature or drying temperature is given.

What is known of the fermentation

Yoghurt brings lactic-acid bacteria into the dough, and the cooked vegetables and cereals supply the sugars and starch they work on, but the sources do not establish which organisms do the work. A comparison of home-made and commercial tarhana found different lactic-acid-bacteria profiles in the two groups, and a 2024 Turkish thesis analysed samples associated with five provinces and noted recipe variation. Those results are bounded by their samples and do not describe a single community for every batch.

The household recipe offers either tarhana or dry yeast as an inoculum for its dough, which shows a cook using tarhana to seed the next ferment. The sources do not test whether dried tarhana reliably restarts fermentation.

Relatives that share the name

The Ministry describes a related yarma or göce variety made with cracked wheat cooked with yoghurt, shaped into small pieces or flat patties and dried; these are soaked before cooking. Greek and Cypriot trahanas are a separate tradition, which may be made with fermented ewe or goat milk and wheat. Kishk is commonly described as a fermented dairy and cracked-wheat food. The name is useful for comparison, but the sources do not show that these share one formula or one microbial community.

A summer-production description in the microbiology literature refers to Greek and Cypriot trahanas and cannot establish a season for Turkish tarhana or kishk.

In the soup pot

Tarhana is a ready-made soup ingredient. The Ministry's soup variations add small cubes of beet and boiled chickpeas. The household author says extra vegetables or chicken are better added when the soup is made than put into the dough, and roasts ground pepper first for her pepper-style soup. She calls it her favourite winter soup, learned from her mother's recipe.

History and what is not established

A 2023 review repeats an account of tarhana arriving in Anatolia with migration, but cites secondary works, and a primary attestation was not found. The sources give no firm origin or season for tarhana, no safe storage period for the dried product, no drying endpoint and no way to revive fermentation from the dried grains. The page records documented practice, not a validated process.