Bovine vs. Plant-based milk: a cost-benefit study
January 14, 2022
Okay, not to be too technical, but the title of this blog is wrong. Plant-based “beverages” are not milk. The term “milk” is a lacteal secretion from a mammal, free of colostrum, obtained from the milking of healthy animals. Bovine milk is from cows, sheep cheese comes from sheep milk, goat milk is from goats, etc. We know these animals are well fed and cared for, the milk is transported to a plant where it is pasteurized, homogenized, and adjusted for fat content prior to processing and packaging. But what do consumers know about plant-based beverages that claim to be milk? They know what oats, soybeans, and almonds are, but you would need to read patent filings in order to understand how these beverages are created in laboratories. We know more about how beer is made than these products. And in terms of nutrition and sustainability, most consumers rely on the marketing information provided by the manufacturers. Or worse yet, they may take advice from websites or movie stars. With regards to tradeoffs between nutrition, environmental impact, and retail cost, it’s doubtful most consumers would have the full picture.
Environmental impact is likely high on the list of consumers seeking alternative plant-based beverages. People like the concept of “Net Zero.” But nothing is free. Any human activity that makes something will result in carbon emissions. So how would you compare bovine milk, which has a relatively higher carbon footprint, to these alternatives? Well, take the case of my friend who wants to purchase a small fuel-efficient car to commute to work each day. This car has much less carbon emissions than a truck or SUV and provides a benefit: getting to and from work. Also, this car has way fewer emissions than the city bus which runs on natural gas. But wait, the bus transports a lot more people to work than a single vehicle. So, on a per person basis, the bus is much more efficient on carbon emissions. Well, the same logic should apply to bovine milk vs. plant-based alternatives. The benefit is nutrition (protein, lipids, carbohydrates, and vitamins/minerals). On the cost side is the retail price and environmental impact.
In Chapter 1 of my new textbook (Table 1.4, pg. 18) I did a cost-benefit study on bovine milk vs. soy, almond, oat, coconut, and rice beverages. I created a nutritional profile per 249 gram serving based on USDA’s FoodData Central (Agricultural Research Service). I then reached out to a researcher from the University of Oxford who published data on the CO2-equiv., water, and land use for plant-based beverages. Finally, I conducted a local price search (dollars per half gallon) and compared the retail cost per 100 kcal of energy for these alternatives to bovine milk. So what did I find?
Plant-based alternatives, on a per serving basis, require much less CO2 and land when compared to bovine milk. But hold on. Just like the comparison of the car and bus, you need to look at this cost relative to other factors. Take almond beverages. They require 3.47 times less CO2 than bovine milk per serving. But, almond beverages provide just 27 kcal of energy per 249 gram serving compared to 149 in bovine milk (due to fat, protein, and carbs). And, almond beverages require 2.5 times MORE water than bovine milk. Finally, in terms of retail cost per 100 kcal of energy, almond beverages are six times more expensive than bovine milk. Other plant-based alternatives do better on the nutrition and water side. In fact, only soy comes close to bovine milk. But most have higher retail costs when compared to bovine milk. Charging families more for less isn’t an attractive societal objective.
I doubt many consumers went to the trouble that I did to develop a methodology, conduct a literature search, contact researchers in other countries for data, and calculate the comparison. To make informed decisions, consumers need improved product labeling (either its “milk” or it isn’t), objective information on nutrition and environmental impacts, and better cost/benefit studies. That way, when they make their way to the dairy case and view all the “milk drinks,” they can make an informed and educated decision.
Dr. Ken