A guide to roasting coffee for plant-based milks

From almond and oat to coconut and cashew, plant-based milks have exploded in popularity over the last few years. According to a 2019 UK study, nearly a quarter of the population drink plant-based milks, with this figure set to rise over the next five years.

The largest demographic of plant-based milk drinkers is 16-24 year olds, whose increasing awareness of dairy milk’s impact on the environment, among other things, have encouraged the search for nondairy alternatives.

As consumers increasingly turn to plant-based milks, coffee businesses have had to adapt to cater to these new demands. For many specialty coffee roasters, this has meant sourcing and roasting coffees that complement plant-based milks.

To find out more, I spoke with three-time National Barista Champion and Starbucks South Africa consultant, Ishan Natalie.

Read next: What is the carbon footprint of a cup of coffee?

What are plant-based milks?

Plant-based milks have been consumed by humans for centuries, but it’s only relatively recently that they’ve entered the mainstream market.

Derived from a range of plants, including beans, nuts, seeds, and grains, they’re typically made by grinding the plant and mixing it with water, minerals, vitamins, and flavourings.

Today, there are dozens of plant-based milks available, from rice to coconut. However, the most popular milks are almond, soy, and oat, making up more than 70% of total sales.

While traditional dairy milks still dominate the market, plant-based milks are on the rise. Buoyed by a surge in vegan diets, sales in the US climbed by 20% between 2019 and 2020, with nearly half of all US shoppers now adding a plant-based milk to their baskets. 

One of the main reasons for this trend is related to sustainability. Research shows that compared to dairy milk, plant-based alternatives use around nine times less land, produce three times fewer greenhouse gases, and consume considerably less water. For example, oat milk requires 48 litres compared to 628 for dairy milk.

What challenges do plant-based milks present for baristas?

Among the most popular uses of plant-based milks is for making coffees. “Barista” versions of oat, almond, and soy milks have become an increasingly common sight on supermarket shelves and coffee shop menus, as demand for these products has surged.

Compared to the regular versions they have a higher fat content, offering a creamier texture that pairs well with espresso-based drinks. In April 2021, Starbucks reported a “shortage” of oat milk across US stores just one month after adding it as an option to menus.

However, for baristas the growing trend in plant-based milks has presented a new set of challenges. Not only does their texture and “mouthfeel” differ to traditional dairy milks, they also contain ingredients that behave differently when added to coffee.

“Most plant-based milks are unsweetened, which is a dietary choice for most.”

Ishan Natalie works as a barista trainer and consultant for Starbucks South Africa. He tells me that one of the biggest problems baristas face with plant-based milks is curdling: the separation of the milk into clumps when it makes contact with brewed coffee.

“I’m currently investigating a commonly reported problem with plant-based milks and coffee, which is curdling,” he says. “Based on feedback and my own research, it seems as though less developed, lighter roasted coffees tend to be the cause.

“Either the sugar content in the coffee in more developed coffees keeps the curdling effect in check, or there is some clash with high acidity in lower developed coffees. I’m yet to see plant-based milk curdling with more developed, darker roasted coffees.”

Another issue is flavour. While most “barista” edition plant-based milks have been adapted to complement the taste of coffee, others tend to produce grainy, cardboard-like flavours that can mask certain characteristics.

In particular, Ishan explains that a lack of sweetness in some nondairy milks can cause espresso-based drinks to fall short.

“Most plant-based milks are unsweetened, which seems to be a dietary choice among most consumers,” he says. “These options lack the sugar content in less developed coffees, which have lower and more refined sugar content, and don’t tend to have the elevated sugar levels that make for a richer, tastier beverage.”

How to adapt roast profiles for plant-based milks

Today, more and more specialty roasters have started to source and roast coffees according to what works best with the addition of plant-based milks.

Ishan explains that in addition to maintaining a balance, roasters need to pay close attention to the body of the coffee. In most cases, this involves developing the coffee for longer.

“More developed coffees will have a richer mouthfeel, which will lend itself well to plant-based milks that often lack body and richness.”

As well as adding body, a longer development time will also provide additional sweetness and lower acidity, therefore reducing the chances of curdling. This is due to what’s known as the Maillard reaction, a chemical reaction between amino acids and reducing sugars that gives coffee its sweet, caramelised flavours and high viscosity.

“In my experience, oat, coconut, and macadamia milks work best with light roasted coffees.”

Ishan tells me to think of it like creating a blend. “Focus on developing coffees that are well balanced, sweeter, and keep acidity in check,” he says.

“It’s always best to look at all the components going into a beverage, and how each complements each other from a like-for-like character, or from a point where they lend their dominant characters to each other where the others lack, to create harmony. 

“For example, in my experience, oat, coconut, and macadamia milks work best with light roasted coffees, whereas almond and soy work best with darker roasts.”

For those who want to appeal to a wider range of customers, this might mean choosing origins that work across all plant-based milks, such as swapping typically acidic East African coffees for those from Central and Latin America. 

“Coffees from this region have higher sensory tones of chocolate, nuts, caramel, biscuit, vanilla, and the like, which meld perfectly with any milk, whether dairy or plant-based,” Ishan explains.

Whether roasting coffee for dairy or plant-based milks, including information on your packaging is essential for consumers. Not only will it help them make informed decisions about the coffee they buy, it will also ensure they get the best out of your coffee.

At MTPak Coffee, we have a team of expert designers who can help you with every step from concept to completion. We can advise on materials, additional components, printing methods, and more. 

For more information on our sustainable packaging, contact our team.

MTPak Coffee

Stay updated about MTPak Coffee’s products & services. Sign up to our free newsletter.