Starbucks adds oat milk to the menu nationwide

Starbucks is rolling out oat milk across the country.

The coffee chain announced on Wednesday that the wildly popular dairy alternative will be available in all stores starting in spring 2021. Starbucks had previously tested oat milk in 1,300 stores around the Midwest.

The chain has been offering the dairy-free alternative in European markets since January 2018. It's also been available at select Starbucks Reserve locations since March 2019. Starbucks is using milk from Oatly, a Swedish oat milk producer that is one of the world's largest.

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Starbucks introduced its first dairy-free alternative — soy milk — in 1997, but over time, market demand for plant-based milks has grown exponentially and the company has evolved its menu accordingly. The coffee giant added coconut milk to its menu in 2015, followed by almond milk (the chain blends its own and calls it Almondmilk) in 2016.

Dairy-free milks are often associated with being a bit healthier and less caloric than whole milk, but they often don't have as much protein and some varieties may be loaded with sugar. For example, a grande Starbucks flat white made with 2% milk has 220 calories, 11 grams of fat, 18 grams of carbs and 12 grams of protein. The same sized drink made with almond milk has 170 calories, 5 grams of fat, 30 grams of carbs and just 3 grams of protein.

Oat milk is made by adding water to oats and then blending. The most popular brands list oats and water as the main ingredients and then sometimes salt and added vitamins and minerals.

Related: Almond milk is so 2018.

Calcium and iron are almost always found in the drink and crowd-favorite Oatly, also fortifies the beverage with vitamins like D and A.

It is possible to make at home as well, just by blending 1 cup oats with 3 cups water.

EDITOR'S NOTE (Dec. 10, 2020, 10:34 a.m. EST): A previous version of this article incorrectly stated that Starbucks introduced soymilk in 2004, but it was actually introduced in 1997.