August 28, 2025 – (Qahwa World) – The coffee world has long been familiar with debates about dairy versus alternatives, but a groundbreaking study from South Korea has now provided the most detailed comparison yet of how nut-based milks perform in espresso drinks. The findings reveal that while cow’s milk remains the preferred choice for taste and texture, nut milks—particularly when roasted—offer unique health advantages and the potential for future innovation in coffee beverages.
Background: The Rise of Plant-Based Milks
Growing concerns over lactose intolerance, cholesterol, and the environmental footprint of dairy farming have fueled global demand for plant-based milk alternatives. Almond, cashew, hazelnut, and walnut milks have emerged as popular options, often promoted for their nutritional value and lower environmental impact. Yet little scientific research has explored how these nut milks behave when combined with coffee, particularly in terms of sensory appeal and chemical composition.
This new study, conducted by researchers at Dongguk University in Seoul and published in Scientific Reports, set out to fill that gap. The team prepared espresso-based beverages using roasted Brazilian arabica coffee and each of the four nut milks, in both roasted and unroasted forms, then compared them against traditional cow’s milk coffee.
The Science Behind Nut Milks in Coffee
The researchers examined multiple factors:
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Fatty acid composition
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Antioxidant activity
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Volatile compounds (aroma contributors)
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Particle size and viscosity
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Color and browning index
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Sensory evaluation by trained tasters
Roasting nuts before milk preparation had a profound impact. Oleic, linoleic, and linolenic acids—all beneficial unsaturated fatty acids linked to heart health—rose significantly in roasted nut milks. These drinks also exhibited higher antioxidant activity and polyphenol content, key markers associated with reduced oxidative stress in the body.
On the flip side, nut-based coffees tended to have larger particle sizes and higher viscosity compared to cow’s milk, factors that influenced mouthfeel and overall smoothness.
Volatile Compounds and Aroma Profiles
Gas chromatography identified 33 volatile compounds across the samples. Cow’s milk coffee stood out for floral and sweet notes such as furfuryl acetate and 5-methyl furfural, while nut milks contained more aldehydes and pyrroles, compounds characteristic of nutty aromas.
For example, almond milk coffee showed high levels of benzaldehyde, the chemical responsible for the distinct bitter-almond scent. Cashew and walnut-based versions contained other aldehydes linked to roasted and woody notes. These chemical profiles shaped the sensory outcomes, sometimes creating bitterness or lingering aftertastes that reduced preference scores.
Sensory Results: Dairy Still Dominates
Seventeen trained panelists evaluated all beverages for sweetness, bitterness, texture, nuttiness, and overall acceptance. Cow’s milk consistently ranked highest for sweetness, creaminess, and general preference.
Among the nut milks, cashew milk scored the highest, followed by almond and roasted hazelnut. Roasted walnut milk was the least favored. The study attributed the lower ratings of nut milks partly to aldehydes that impart undesirable flavors and to textural differences caused by larger particles.
Despite this, researchers stressed that nut milks still show strong promise:
“Nut-based milk coffee demonstrated potential as a health-promoting beverage owing to its high unsaturated fatty acid content and antioxidant effects,” the authors wrote.
Health and Sustainability Advantages
Nutritionally, nut milks have clear advantages. Compared with cow’s milk, they contained:
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Lower levels of saturated fat
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Higher levels of unsaturated fatty acids (linked to cardiovascular benefits)
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Greater antioxidant activity (especially in roasted versions)
From an environmental perspective, the use of nuts in plant-based beverages reduces reliance on livestock farming, which is resource-intensive in terms of water, land, and greenhouse gas emissions.
The Road Ahead: Improving Flavor and Texture
While health benefits are evident, the researchers acknowledged that consumer acceptance remains limited by flavor and mouthfeel. They recommended further work to:
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Control aldehyde production during processing to minimize off-flavors
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Conduct additional physical experiments to refine texture and improve creaminess
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Explore roasting parameters to optimize antioxidant release without compromising taste
These steps, they argue, could help close the sensory gap between nut milks and cow’s milk, paving the way for a new generation of plant-based coffee beverages that balance health, sustainability, and taste.
A Shift in the Coffee Industry?
The study’s findings come at a time when cafés worldwide are diversifying their menus with oat, soy, and nut milks to cater to vegan and health-conscious consumers. While dairy still dominates, particularly in espresso-based drinks, this research signals that the future of coffee could include more scientifically engineered plant-based options that rival dairy not only in nutrition but also in flavor.
For coffee lovers, that could mean healthier cappuccinos and lattes without sacrificing the sensory experience that makes café culture so irresistible.
