Matsoni in Georgia and matsun (also written matzoon) in Armenia are the same thing: the everyday fermented milk of the South Caucasus, thick and mildly tangy, eaten plain, with honey or fruit, in soups and as a base for sauces and drinks. Researchers describe it as a national food of both countries (Bokulich et al., 2015). Households traditionally set each batch with a spoonful of the last.
What Makes Matsoni
Studies of traditional Georgian matsoni found it dominated by the two classic yogurt bacteria, Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, with other lactic acid bacteria such as Lactobacillus helveticus, Lactobacillus paracasei and Leuconostoc lactis in high numbers too (Quero et al., 2014). A survey of matsoni from many regions of Armenia and Georgia found Lactobacillus and Streptococcus dominating everywhere, while the yeasts – Kluyveromyces marxianus, Saccharomyces cerevisiae and others – differed by region and milk type, so each area’s matsoni carries its own microbes (Bokulich et al., 2015). Researchers have built starter cultures from strains isolated from traditional matsoni (Kakabadze et al., 2021).
Because its main bacteria are heat-loving (thermophilic), matsoni is set warm, the way yogurt is.
Matsoni vs Caspian Sea Yogurt
Many recipes online describe a different product. “Caspian Sea yogurt”, popular in Japan, is a ropy, room-temperature fermented milk made by two strains isolated from Caucasian fermented milk: Lactococcus lactis subsp. cremoris and Acetobacter orientalis (Ishida et al., 2005). The lactococcus produces the polysaccharide that makes it stretchy (Uchida et al., 2009). It is a fine fermented milk – closer to Finland’s viili – but it isn’t the matsoni studied in Georgia and Armenia. If a “matsoni culture” you buy sets on the counter and turns stringy, it is this kind.
Making It at Home
Use pasteurized milk: raw milk can carry harmful bacteria, and fermentation doesn’t reliably make it safe (CDC). For a starter, use matsoni from a Georgian or Armenian shop, a matsoni starter culture, or – closest to the bacteria found in studies – a plain live-culture yogurt. The method (recipe card below) is the same as for homemade yogurt: heat the milk, cool it to warm, stir in the starter and keep it warm until it sets. Matsoni is usually eaten softer and less sour than strained yogurt, so check it early.
Keep it cold and eat it within a few days. Traditional matsoni has a short shelf life – 72 to 120 hours at 6°C in one study – which is why researchers have worked on better starter cultures to extend it (Quero et al., 2014).
How It’s Eaten
Matsoni is eaten plain or with honey and walnuts (no honey for babies under 1), thinned with water and salt into a cooling drink (much like Turkey’s ayran or Iran’s doogh), used in cold and warm soups, and as a base for garlicky sauces for meat and vegetables.
Like yogurt with live cultures, matsoni is easier for many lactose-intolerant people to digest than milk: the European Food Safety Authority accepted that live yogurt cultures improve lactose digestion (EFSA, 2010). Claims that it explains long life in the Caucasus aren’t supported by studies.