Mishti Doi

Mishti doi (Mishti Doi / মিষ্টি দই) is a sweet from the Bengal region made by fermenting and setting sweetened milk. When you put a spoon in, it holds together and can be scooped, and sweetness and a mild acidity layer over the rich taste of milk. Mishti means “sweet,” and doi means fermented milk. Because the milk is boiled down and sugar or gur is added before fermentation, it sets with the sweetness spread throughout the milk.

Concentrating, then setting

The milk is first heated, and water is evaporated to concentrate it. Not only the milk fat but also milk solids such as milk proteins and lactose become more concentrated, which affects the mouthfeel and how the milk sets. Depending on whether cow’s milk, buffalo milk or a mixture of the two is used, and how far it is boiled down, the result varies even under the same name.

Next, the milk is cooled and fermented milk is added as a starter. The method of setting aside a small amount from the previous batch and transferring it to new milk is called back-slopping. Lactic acid bacteria produce lactic acid from lactose, and as the milk becomes acidic, its proteins coagulate, creating a smooth structure. The heated milk is cooled before the starter is added so that it reaches a temperature at which the lactic acid bacteria can work.

In artisanal production, leaving it overnight to set is a widely used method. However, the time needed for fermentation varies with the season, the activity of the starter and the container. While some makers wrap the containers in cloth to keep them warm in winter, industrial production uses selected cultures and controls the fermentation temperature. An interview-based study in North Bengal also recorded examples of mixing buffalo milk into mainly cow’s milk, as well as differences in containers and in methods of keeping the milk warm. The milk blend and the way warmth is maintained are adjusted according to the season and the workshop.

Mishti doi scooped with a spoon. The soft texture of the milk is visible. Photo: Billjones94, 2021-10-15, Kolkata, India. Original image / CC BY-SA 4.0. Downscaled version from the source; no additional processing.

White doi, red doi, and doi in a basket

The color ranges from nearly milky white through pale cream to reddish brown. In some methods, sugar is caramelized separately and added to the milk; in others, the milk is heated for a long time to deepen its color and its cooked-milk flavor. Even when gur is used, the color and aroma vary depending on its source and how it is boiled down. How the sugar is caramelized, how the milk is heated and which sugar is used are each factors that create the color.

Nolen gur, used during the Bengali winter, is a new-season sugar made from the sap of date palms. Like cane sugar, it provides sweetness, and it also brings the aroma of boiled-down sap. Versions made with white sugar and versions made with nolen gur are both enjoyed under the same name, mishti doi.

Lal doi, known in Nabadwip, is distinguished by its reddish color and richness. For kheer doi from Gangarampur, milk is boiled down to a thick state called kheer before it is fermented. In Murshidabad, some jhuri pata doi uses as its container a bamboo basket whose inside is sealed with thick milk. Regional differences appear not only in the level of sweetness but also in how far the milk is concentrated and what it is set in.

Bogura in Bangladesh is another place known for sweet doi bearing the town’s name. In the workshops of Sherpur, earthen pots filled with sweetened, boiled milk and starter can be seen lined up around the hearth and covered with half-moon-shaped woven baskets so the doi can set. Even the way the vessels are placed and covered during fermentation reflects the ingenuity of workshops organized around the hearth.

Bogura’s doi spread from the Sherpur workshops throughout the district, and it is also supplied to shops in Dhaka and to hotels along the Dhaka–Rangpur highway. In addition to collecting milk locally, the work of firing unglazed containers and making rope from dried rice leaves is also connected to the distribution of this sweet. In 2025 interviews, producers spoke of overseas shipments they had made, and of maintaining quality during long-distance transport as a challenge. This earthen-pot sweet bearing the name of its locality has also become an industry that links workshops, container makers and sellers.

A sweet eaten from unglazed earthenware

Unglazed earthenware vessels are closely associated with mishti doi. Their porous walls absorb moisture and let it escape outward, which helps concentrate the milk. A small vessel can also serve directly as a single-serving dish. Today, mishti doi is also made in plastic cups and large metal containers, with the container chosen according to the scale of production and the way it is sold.

This sweet fermented milk belongs to the food culture of Bengal, which spans West Bengal and Bangladesh. It is served not only as a dessert after meals but also at weddings and other celebrations, at festivals and as a gift to relatives. Whether a large quantity is prepared for a wedding table or a single vessel is given when visiting relatives, the sweet milk is delivered still set.

Mishti doi in unglazed earthenware vessels. Vessels of different sizes are used as they are for selling. Taken in 2015. Photo: Anwesha394. Source: Wikimedia Commons, CC BY-SA 4.0. The image has not been altered.

Outside Bengal, too, this sweet fermented milk can be found in sweet shops and supermarkets. A person who lived in New Delhi wrote of buying mishti doi in an unglazed earthenware vessel at a small sweet shop recommended by their cooking teacher. Even in cities far from its home region, it is enjoyed as a treat to take home in its vessel.

Glossary