Milks from grains
We can produce plant-based milk from almost any grains, but rice and oat are proving popular. However, they require more land compared with nut milks.
Rice milk has a big water footprint. More notably, it’s associated with higher greenhouse gas emissions compared to the other plant-based options because methane-producing bacteria develop in the rice paddies.
In some cases, rice milk may contain unacceptable levels of arsenic. And applying fertilisers to boost yields can pollute nearby waterways.
Oat milk has been becoming increasingly popular around the world because of its overall environmental benefits.
But similar to soy, the bulk of oat production is used for livestock feed and any reduction in the demand for animal-based foods would decrease the pressure on this plant.
Currently grown in Canada and the US, most oat operations are large-scale monoculture, which means it’s the only type of crop grown in a large area. This practice depletes the soil’s fertility, limits the diversity of insects and increases the risk of diseases and pest infection.
Oats are also typically grown with glyphosate-based pesticides, which tarnishes its environmental credentials because it can cause glyphosate-resistant plant, animal and insect pathogens to proliferate.
The final message: diversify your choices
Organic versions of all these plant-based milks are better for the environment because they use, for example, fewer chemical fertilisers, they’re free from pesticides and herbicides, and they put less pressure on the soils. Any additives, be it fortifiers, such as calcium or vitamins, flavours or additional ingredients, such as sugar, coffee or chocolate, should be taken into account separately.
Packaging is also very important to consider. Packaging contributes 45% of the global warming potential of California’s almond milk.
And it’s worth keeping in mind that wasting milk has a much bigger environmental footprint, and questions the ethics of how humans exploit the animal world.
If, as a consumer you are trying to reduce the environmental footprint of the milk you drink, the first message is you should avoid dairy and replace it with plant-based options.
The second message is it’s better to diversify the plant-based milks we use. Shifting to only one option, even if it’s the most environmentally friendly one for the time being, means the market demand may potentially become overexploited.
Authors: , Postdoctoral Researcher, Curtin University
Professor of Sustainability, Curtin University and