DIY oat milk and the plant milks of the world

Grind a seed, a nut or a tuber in water, then strain it: several cuisines have made a plant “milk” this way for centuries. Valencian horchata, Chinese doujiang and medieval almond milk each have a written history. Oat milk has none: it is a process developed in Sweden in the 1990s. We present it for what it is, with a DIY oat milk method in grams at the end of the article.

Five plant milks, one method

From one country to the next the principle barely changes: grind, add water, strain. What differs is the starting ingredient and how long people have been doing it.

Milk	Where	Made from	Earliest written trace
Horchata de chufa	Valencia, Spain	tiger nuts	13th century
Doujiang	China	soybeans	around AD 82 or 1365, depending on the source
Almond milk	Middle East, then Europe	almonds	1226 at the latest
Coconut milk	South and Southeast Asia, East African coast	coconut flesh	not dated here
Oat milk	Sweden	rolled oats	1990s

Horchata de chufa in Valencia

Horchata de chufa, orxata de xufa in Valencian, is not made from a grain but from tiger nuts, which are small tubers. They reached the Iberian Peninsula in the 8th century, under Muslim rule, and took root around Valencia, where 13th-century records already mention a drink of this kind. Today horchata is associated with Alboraya, in the province of Valencia, and a designation of origin, Chufa de Valencia, covers the tiger nuts grown in sixteen Valencian municipalities.

The tiger nuts are washed, ground, left to steep and pressed several times; the extract is then sweetened and sieved once more. Horchata is served with fartons, a local pastry. The name probably comes from the Latin hordeata, from hordeum, barley. In Mexico the same word means a different drink, made from rice, cinnamon and sugar.

The rest of the vegetarian table in Spain is covered in eating vegetarian in Spain and Portugal.

Doujiang, breakfast in China

Doujiang (豆浆) is fresh soy milk as it is drunk in China. William Shurtleff and Akiko Aoyagi, who wrote a history of soy milk, describe the basic Chinese method: the soybeans soak overnight, are ground on a stone mill to a thick purée, mixed with water, usually cold, and strained through cloth. The milk is then boiled for ten to twenty minutes before serving.

It is drunk hot or cold, sweet or savoury. Tian doujiang, the sweet one, is drunk warm early in the morning or late at night. Xian doujiang, the salty one, is eaten as a hot, spicy breakfast soup garnished at the table, and it is sometimes lightly curdled with vinegar. The garnishes Shurtleff and Aoyagi list include bonito flakes and bits of shrimp: for a vegetarian bowl, keep the diced leek, salt pickles, salt and spices. Both come with youtiao, long fried dough sticks dipped into the piping hot milk, sometimes wrapped in a sesame flatbread.

In the morning, congee is eaten across much of China too. Other morning traditions are gathered in our article on savoury breakfasts around the world.

When doujiang first appeared is not settled, and the sources disagree. Shurtleff and Aoyagi point to a first mention of the word around AD 82, in the Lun Heng by Wang Chong, while noting that it may then have meant a soybean purée soup rather than a strained milk. Wikipedia, in its article on plant milks, dates the first recorded use of soy milk in China to 1365. We do not choose between them. As for the tradition that credits Prince Liu An with soy milk in the 2nd century BC, no historical record supports it. In its oldest written versions, the legend credits Liu An with tofu alone; later writers, in Asia and in the West, added soy milk to the story.

Soy milk is also the first stage of tofu: it is curdled, and the curds are pressed into blocks. Mapo tofu and our notes on cooking tofu so it is never bland start from there. In the kitchen, its lecithin lets it emulsify like an egg yolk, which is how it makes the aioli for our patatas bravas.

Almond milk, from the Middle East to Lent

The oldest known almond milk recipes go back at least to the 13th century in the Middle East: almond milk appears in the Kitab al-Tabikh, The Book of Dishes, written in 1226 by Muhammad bin Hasan al-Baghdadi. In the Middle Ages it spread across Europe, where it replaced animal milk in areas that followed Catholic fasting rules, especially during Lent. It was made by simmering ground almonds in water, and it was expensive. On fast days, a thin split-pea purée, sometimes enriched with almond milk, stood in for meat broth.

Coconut milk, a milk for cooking

Coconut milk is above all a cooking ingredient. It is made by pressing grated coconut flesh with a little warm water: the first pressing gives a thick milk, the second a thin one. It belongs to the cuisines of South and Southeast Asia and the East African coast, often in curries. We have given it a whole article, coconut milk, from Kerala to the Caribbean.

Oat milk, a 1990s invention

Oat milk is not a tradition. It was developed in the 1990s at Lund University in Sweden by the food scientist Rickard Öste, who founded the company Oatly in 1994 with his brother Björn.

The industrial process explains the texture of carton oat milk. The oats are ground in warm water, then enzymes called amylases break their starch down into smaller pieces. The liquid is separated from the solids, often fortified, then pasteurised. At home there are no enzymes and the starch stays whole: it is what turns oat milk slimy when it is blended too long, when the pulp is squeezed or when it is heated.

Making DIY oat milk

• 100 g rolled oats
• 800 g (800 ml) very cold water
• 1 pinch of salt

1. Put the oats, water and salt in the blender without soaking them first: a long soak makes the milk slimy.
2. Blend for about thirty seconds, no longer.
3. Pour into a nut milk bag, or a clean, fine tea towel set in a sieve, and let it run through without pressing the pulp. For a smoother milk, strain it a second time.
4. Bottle it and keep it in the fridge. It separates as it stands, which is normal: shake it before serving, and drink it within the next few days.

It will not froth the way carton oat milk does. For a thinner milk, add water after straining. A little vegetable oil blended with the oats makes it creamier and a syrup sweetens it; both are optional.