Cattle produce more methane than any other livestock. Methane, a greenhouse gas, traps heat, which warms the Earth. It is far more powerful than its more common counterpart, carbon dioxide.

When cows graze, microbes in their stomach break down their food and make methane. Cows then belch and fart that methane into the Earth’s atmosphere, through a process called enteric fermentation. The U.S. Environmental Protection Agency estimates that just one cow can emit 154 to 264 pounds of methane gas into the atmosphere each year. 

With more than 28 million beef cattle in the U.S., that is more than 4 billion pounds of methane — the weight of at least 20,000 blue whales.

Agriculture emits 10% of the total U.S. greenhouse gas emissions. The sector trails behind others, including electric power (25%) and transportation (28%). Within the agricultural sector, however, cattle production is estimated to be the biggest methane culprit linked to U.S. consumption.

The U.S. as well as other major beef-producing countries including Brazil, Argentina, France and Germany have been intent on slashing global methane emissions by at least 30% from 2020 levels by 2030, a goal under the Global Methane Pledge. One solution? Eating less beef. 

“It’s hard to get people to reduce their meat consumption in general,” said Kelly Davidson, a University of Delaware assistant professor of applied economics. “We all have tastes and preferences, social norms and cultural practices around what we eat. Having grown up on a cattle farm, it would be hard to convince me to not eat beef.”

Meanwhile, many countries have approved feed supplements that, if added to cows’ diets, could curtail the methane emitted from cattle burps and farts.

Davidson and a team of researchers from UD’s Department of Applied Economics and Statistics in the College of Agriculture and Natural Resources were curious if U.S. consumers would purchase ground beef from cows fed one of three methane-reducing additives.

It turns out, consumers would rather stick with conventional ground beef. But when given information about greenhouse gas emissions and methane-reducing additives before making a purchase, consumers opted for ground beef from cattle given feed with the seaweed additive. The researchers published their findings from a national consumer survey in the journal Food Policy.

Curtailing methane burps

Feed additives that work to curb cattle methane emissions, including organic compound 3-nitroxypropanol (3NOP) and essential oils, are already on the market in the European Union, Brazil, Chile and Australia. 

The U.S. Food and Drug Administration in May approved 3NOP as a feed additive for lactating dairy cows only. Meanwhile, several U.S. companies are researching and developing seaweed as a potential cattle feed additive. 

Sarah Meyer, who graduated UD in 2022 with a master's degree in Agricultural and Resource Economics, and is a co-author on the paper, said between the three solutions, seaweed has the potential to reduce methane emissions the most.

“The seaweed feed additive has the potential to reduce a cow's methane emissions up to 95%,” Meyer said. “So if every U.S. cattle producer implemented this practice, the agriculture industry would experience major methane emissions reductions which could help the U.S. achieve its 30% methane emissions reductions targets by 2030.”

After reading an article in The Economist about how seaweed could be a solution to livestock’s methane burps, Meyer wondered how interested consumers would be in buying beef from cattle that consumed feed supplemented with the seaweed additive. 

“Finding efficient ways to reduce cattle emissions that consumers are interested in that aren’t as costly is important,” Meyer said. “A lot of times there are barriers to cost or people have to completely change their habits to be more environmentally conscious. People aren’t always willing to pay more or change their habits or behavior to reduce emissions.”

Consumer preference

The researchers collected data from 3,009 ground beef consumers through a 2022 online survey. They randomly assigned people into two large groups: one group was offered a 1-pound package of ground beef at low prices and the other was offered a 1-pound ground beef at high prices.

Consumer groups were shown different ground beef prices from $3.79 to $9.24 based on U.S. Bureau of Labor Statistics data and realistic grocery store prices.

Survey respondents were further broken into subgroups for each price group and given varying levels of product information ranging from advanced information about methane emissions that come from cattle production, to labels about decreased emissions possible by methane-reducing additives, to no information at all.

“Overall, people preferred conventional beef at the lowest price,” Meyer said. “However, when people were given pre-purchase information and a label, people would choose the seaweed alternative over conventional beef and would potentially be willing to pay more for it.”  

Consumers given no information or labels on methane emissions were more willing to pay higher prices for conventional ground beef than for ground beef from cattle fed any methane-reducing additives, up to $2.50 more.

Meanwhile, consumers given information about methane emissions from cattle production and a label showing feed additives’ potential to curb methane were willing to pay about 36 cents more for 1 pound of low-methane ground beef from cattle fed seaweed over what they would pay for conventional ground beef.

Davidson said it’s not surprising that consumers would rather buy conventional beef. Even though a growing number of environmentally conscious consumers are willing to pay premiums for products with an environmental impact, many food consumers gravitate towards what they know they like and can afford.

“I think it goes back to those social norms and preferences,” Davidson said. “And the average consumer pays most attention to price when making food purchasing decisions. The emissions label is a way to nudge behavior toward a more environmentally conscious choice.”  

Given environmental information about methane emissions from cattle production before purchasing a product, consumers were slightly more willing to purchase ground beef from cattle fed essential oils than seaweed additives. Yet when shown more information and a label about methane-reducing additives and their impact on emissions, interest in the seaweed additive picked up steam. 

According to animal science researchers, each feed additive has the potential to lower methane emissions by a different rate if universally used by cattle producers:

• Seaweed could reduce cattle methane emissions by up to 95%.

• 3NOP offered a 40% average reduction rate.

• Essential oils provided a 23% average reduction.

Multiplied by this study’s predicted portion of the market buying low-methane ground beef:

• They found that if farmers fed their cattle the seaweed additive and consumers bought low-methane ground beef without any information on greenhouse gases or emission reductions, seaweed additives could cut methane emissions by 13-14%.  

• If seaweed, essential oils and 3NOP are all used, they could altogether reduce methane emissions up to 48% if consumers buy low-methane beef after seeing information campaigns and labels. 

Davidson said these results show how demand for low-methane beef and the market can drive a shift in methane emissions.

“Consumers can drive the market for seaweed-fed beef,” Davidson said, “but it’s going to take policymakers investing in labeling and information campaigns to build consumer awareness about the potential for low-methane beef.”

Informing policy

With the Global Methane Pledge’s 2030 goal of curbing methane emissions of at least 30%, the UD researchers say their study can inform policy and strategies to slash methane emissions. 

Since the seaweed feed additive received the highest consumer interest and having the largest potential to curb methane emissions, the researchers recommend global policymakers consider setting aside funding for this market and paving the way for approval. 

The research paper, Consumer preferences for low-methane beef: The impact of pre-purchase information, point-of-purchase labels, and increasing prices, is authored by Kelly Davidson, Brandon McFadden, Sarah Meyer and John Bernard. It was published in the journal Food Policy. The study was funded by start-up funding from the UD College of Agriculture and Natural Resources and USDA NIFA Hatch funding, grant #14009178