If you want to learn how to steam soy milk, you’re not alone. Soy milk generated over $972 million in revenue in 2024 alone, and it’s been a leader in the nondairy milk industry for years.
If you’re looking to swap out your dairy milk for an alternative, then you won’t find a better option than classic soy milk. Available almost everywhere, once you learn how to steam it properly you’ll be able to make all of your favorite drinks.
What is the difference between steaming and frothing soy milk?
Steaming and frothing might sound similar, but they’re two different techniques. Frothing soy milk involves aerating the milk to create a thick and silky layer of foam. The milk can be hot or cold when it’s frothed, but it usually works best with heat. You also don’t need any specialty equipment to froth milk, although again, it does work best with the proper tools.
Steaming soy milk, however, is only for hot drinks and requires a steam wand. It’s the best way to create the microfoam so many coffee drinks require. The equipment here is crucial, and there’s really no good way to steam your milk without a steam wand. It’s also the only way to create the professional-quality froth you’re used to getting at high-end cafes, meaning a silkier, denser texture.
Can you heat up soy milk?
Yes, of course, you can heat soy milk. It would be impossible to make hot soy lattes and cappuccinos if you couldn’t! That said, you should pay attention to the temperature and heat it gently the way you would dairy milk. Soy milk can curdle just like dairy milk can, so make sure it’s only heated to 110°F.
You don’t need any special equipment to heat soy milk. You can microwave it on low power in short bursts to ensure it doesn’t overheat. You can also heat it gently in a pot on the stove. You can’t use either of these methods to steam it, though.
What to know about steaming soy milk before you get started
In learning how to steam soy milk, there are just a few important things to keep in mind, including how it reacts to heat and proper temperatures.
Soy milk reacts differently to heat from regular milk
Like other non-dairy milks, soy milk reacts differently to heat than regular milk because it lacks the levels of fat and certain proteins that dairy milk has. That means the structure of its foam may be less stable and have a different mouthfeel than dairy milk. It also means it can be a little more finicky to figure out, but you can still treat it the same way as regular milk.
Luckily, there are barista blends that fortify the soy milk with the extra structure it needs to perform better when it’s steaming and frothing. The stabilizers it has help give it the smoother texture you’re looking for in espresso drinks.
The ideal steaming temperature
Because soy milk can scald and curdle, knowing the right temperature to bring it to can help you avoid those pitfalls. The sweet spot for steaming soy milk is 130-150°F (55-65°C). When you push those temperatures above 160°F, it can cause separation and an unpleasant, grainy texture. Keep a thermometer on hand to monitor the temperature until you get the feel for it.
Choosing the right soy milk for steaming and frothing
Like with all alternative milks, you should look for a barista blend soy milk for your espresso drinks. It’s specially formulated for steaming and its stabilizers help hold foam much better than regular soy milk. If you’re checking the label for ingredients, keep an eye out for emulsifiers like sunflower lecithin, which are essential for microfoam. You should also do your best to use the freshest soy milk available. The older the soy milk, the worse it may be able to froth and hold the foam.
How to steam soy milk
With the right soy milk, you’re ready to start whipping up your favorite coffee drinks at home. Here’s how to do it with a steam wand:
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Pour cold, fresh soy milk into a metal milk jug.
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Place the steam wand with its tip just below the surface and start aerating for 3-5 seconds.
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Lower the wand to integrate air smoothly, creating fine-textured microfoam.
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Stop steaming when the pitcher is warm to touch (around 140°F).
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Tap and swirl the pitcher to break large bubbles and refine the texture.
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Wipe the steam wand clean, and that’s it!
Common issues when steaming soy milk
As you start learning how to steam soy milk, you’re likely to encounter some common issues. Here’s a brief overview and how to handle them:
Curdling
Curdling happens when soy milk is heated too quickly or to an excessively high temperature. To prevent it, keep the steam temperature between 130-150°F and avoid sudden heat spikes. Using barista-blend soy milk with stabilizers reduces the risk of separation. If curdling occurs, try steaming at a slightly lower temperature and adding the milk to the coffee slowly.
Large bubbles
Large bubbles result from too much air introduced too quickly at the start of steaming. Begin with the steam wand just below the surface to aerate evenly. Once froth forms, lower the wand deeper into the milk to smooth out the texture. After steaming, tap the pitcher on the counter and swirl the milk to eliminate excess bubbles.
Watery texture
Watery froth occurs when air isn't properly incorporated during steaming. Ensure proper aeration by introducing air early, within the first few seconds of steaming. Maintain steady movement of the steam wand to create a consistent microfoam. For better frothing, use a steam wand with strong pressure, like those found in high-quality espresso machines.
Get the perfect pour with Pesado!
Now that you know how to froth soy milk, you can start making all your favorite espresso drinks with the help of Pesado. Pesado’s collection of professional-quality accessories, from portafilters to distribution tools, is designed to help you make the best coffee possible. Our stainless steel milk jugs are the perfect place to start.
