Does Soy Milk Froth? Read this First!

Another sad-looking six-dollar soy latte from your local cafe is bound to leave you with just one question: Does soy milk froth or what?

Glass of soya milk with froth on bamboo mat with soya beans - Does Soy Milk Froth

If you are trying to eat healthier, then reducing the amount of dairy in your diet is a great place to start. But can you ditch the cow's milk in your favorite espresso drink and still enjoy a layer of dense froth? Well, yes, you can, as long as you choose the right brand of soy milk and have a loose definition when it comes to the term ‘froth.'

Foam VS Froth

Some folks may use the words “froth” and “foam” interchangeably, but there are distinct differences between the two. Find out if you have been drinking real froth or just foam all these years. 

What is Foam?

milk bubbles evident on top of hot coffee drink
This is foam. Notice the fluffy appearance and large bubbles.

Have you ever ordered an espresso drink at your local cafe, and the froth layer on top was mostly just a lot of giant bubbles that popped and fizzled out to nothing but a milky ring clinging to the edge of the cup? Well, that was foam, not froth. 

Foam requires much less technique to produce than proper froth, and it's the end result of the majority of at-home baristas, as well as many ‘professionals.' It is 100-percent possible to make foam using some brands of soy milk at home. 

What is Froth?

white coffee cup with creamy froth
This is proper froth. Compared to foam, you can see smaller, finer bubbles and thicker consistency.

On the other hand, froth has microbubbles that form a denser layer that not only lasts longer but has a much creamier mouthfeel. The best gourmet cafes usually have the best froth, and once you taste it, you will easily be able to tell the difference. 

But making actual froth using soy milk is a problem. Although some top-end baristas can make really good soy milk foam, it will never have the tight, tiny bubbles that make froth, well, froth. 

The Reason Some Milk Froths Well, and Some Don't

It's all about protein. During the frothing process, the steam wand's heat and movement combine to unwind the coiled protein strands and thicken the milk. This transformation of the proteins helps form the froth's fine bubbles and prevents these bubbles from falling apart too quickly. 

Unfortunately, the proteins in soy milk are much weaker than those in dairy. However, there is a pretty good solution that you can try if you want better results. According to the folks at Cook's Illustrated, the key to successfully frothing non-dairy milk is to purchase a brand that contains gellan gum. 

Gellan gum is a food additive that helps stabilize and gel loose liquids, giving them a thicker consistency without affecting the flavor. The gellan gum binds with the calcium in soy milk to provide a more substantial structure for the bubbles to form around. And don't worry if you are a vegetarian or vegan; gellan gum doesn't contain any animal products!

How to Increase Your Chance of Better Soy Milk Froth

making milk froth in a glass using an electric milk frother
Learn few tricks here to improve how it foams

Besides choosing different soy milk at the supermarket, you can use a few other tricks to improve how it foams. 

Watch the Temperature

Soy milk doesn't like it when things get too hot. While the preferred milk frothing temperature is around 145 degrees, if you take soy milk that high, there's a good chance you will end up with curdled milk. Instead, aim for a temperature that is about 10 degrees lower.  

Don't forget that you should always start steaming with a cold pitcher and cold soy milk. Keeping temperatures as low as possible will allow you to use the steam wand to incorporate air without raising the temperature too quickly. 

Stay Away From Anything Acidic

Acidity and soy milk don't get along very well, so your best bet is to minimize any direct contact between the two. Sadly, many coffees naturally have a high acidity level. Therefore, if you know that you will be using soy milk in an espresso drink, think ahead and low-acid coffee beans.

Despite what you may think, roasting beans for longer doesn't increase the coffee's acidity but lowers it. In addition, blended coffees are often less acidic than single-origin beans. So give dark roasted coffee blends a try and see if it makes a difference.

Final Word on Does Soy Milk Froth

When you combine good techniques and the right brand of soy milk, you can certainly make good foam and passable froth for your cappuccinos or lattes. Just don't expect cow's milk texture, and you shouldn't be disappointed. 

FAQs About Does Soy Milk Froth

Which brands of soy milk froth best?

If you enjoy soy lattes or cappuccinos regularly, it is hard to beat 365 Everyday Value, Organic Soymilk Unsweetened from Whole Foods. At about three bucks for 64 oz, it is inexpensive, organic, and does a decent job at frothing. 

If money's no object, many folks love the Barista Series from Pacific Foods. It isn't cheap at about seven bucks for a 32 oz container, but with its unique formulation for better frothing, it offers impressive results. Interestingly, this soy milk substitutes carrageenan for gellan gum in its long list of ingredients. 

Do I have to use the steam wand on an espresso machine to froth soy milk?

No, there are many other acceptable ways. Perhaps the easiest is to use an automatic frothing pitcher. Just be aware that if your pitcher turns itself off based on temperature, you will need to manually turn it off to prevent the soy milk from overheating.

In addition, you can use any other method people use to froth cow's milk, with maybe a few adjustments. 

Author

  • Jared Bernstein worked in the food industry for decades, starting as a barista in high school. He graduated from the Institute of Culinary Education in NYC and worked in some of the city's top-end restaurants. When he isn't writing about cooking or historical recipes, he's probably hanging out at a classic diner or cafe.