thayir

Thayir is the Tamil word for yogurt or curd, a dairy product produced by fermenting milk with lactic acid bacteria. It is a staple in Tamil Nadu and other parts of South India and is used both as a dish component and as a cooling accompaniment to meals.

Preparation involves warming milk and allowing it to cool to about 40-45°C, then adding a starter from a previous batch or plain yogurt. The mixture is kept warm to incubate until it thickens into curd. Traditional thayir is made from cow or buffalo milk; plant-based milks can be used, but are less common in classical preparations.

Culinary uses include thayir sadam (curd rice), where seasoned curd is served with rice and a tempering of mustard seeds, curry leaves, and dried chilies. Thayir kuzhambu is a curd-based curry with vegetables; thayir pachadi refers to yogurt mixed with cucumber, onion, or mango, often tempered with mustard seeds and curry leaves; boondi thayir is yogurt with fried chickpea flour pearls.

Nutritionally, yogurt provides calcium, protein, and live bacteria that can aid digestion. Fermentation can make some of the lactose more digestible for some people, and the fat content depends on the milk used.

Storage and safety: Because it is perishable, thayir is typically refrigerated and consumed within a few days. It should be discarded if it develops an off smell, mold, or unusual texture, and kept separate from raw foods to prevent contamination.

In everyday life, thayir is a common component of meals in South India and appears in various regional recipes and festive offerings, reflecting the role of dairy in the regional cuisine.