Is Kerrygold butter made with milk from grass-fed cows? A new lawsuit filed in California claims the beloved Irish butter brand is misleading consumers into thinking their cows are fed an exclusive grass diet when they also eat grains and soy.

Beloved Irish butter Kerrygold is the subject of a class action lawsuit in California that alleges the butter's claim to be made of milk from "grass-fed cows" is misleading.

Kerrygold Butter and its parent company, Ornua, are being sued for including allegedly misleading claims about using milk from grass-fed cows in their advertising and on their packaging.

Read More: Selling Kerrygold butter is no longer a criminal offense in this US state

California man Dyami Myers-Taylor submitted a complaint claim to the southern district court of California, arguing that:

"Kerrygold products contain the grass-fed claims, which were and are false, misleading, and deceptive claims and advertisements set forth on packaging, labeling and in advertisements as alleged herein."

Hold up - Kerrygold ISN'T made with milk from grass-fed cows?

Not entirely, apparently. Per the Irish Times, Kerrygold's Irish cows often eat grains or soy when the weather is bad or has resulted in a poor yield of grass for the year.

Myers-Taylor, a real estate executive based in San Diego, was a frequent consumer of Kerrygold's range of dairy products from 2014 to 2018 because he believed them to be made with the milk of cows fed solely grass.

He claims to have been deceived and argues that he would not have paid "premium prices" for Kerrygold had he known their cows' diets also included grains and soy.

Read more: A new health craze: Kerrygold butter in your morning coffee (VIDEO)

The complaint, which runs 30 pages and was submitted by attorneys Reuben D. Nathan and Ross Cornell, also states, "On information and belief, the Kerrygold products are derived from cows that are fed soy, corn and other grains, among other non-grass feed, including grains that are genetically modified, and are thus not "grass-fed" as advertised."

Kerrygold, the best-selling butter in the US, second only to Land O'Lakes, is prized by consumers for its pure taste and quality. Milk from grass-fed cows is believed to be healthier, especially for consumers struggling with high cholesterol, and plays a big role in the Ketogenic diet and the Bulletproof Coffee health trends. It has also long been thought to give Kerrygold butter its rich yellow hue.

In another recent lawsuit centering on Kerrygold, Wisconsin residents sued their state's dairy board to change a regulation that made it illegal to buy and sell Kerrygold butter. A number of those who petitioned complained that they had been advised by their doctors to purchase Kerrygold as a healthier alternative because it is derived from grass-fed cow's milk.

Read more: Butter battle spreads as Kerrygold sues Wisconsin-approved rival Irishgold

In a statement to the Fora.ie website, Ornua, which owns Kerrygold, said "we believe our products are marketed in accordance with applicable laws and regulations and will vigorously defend claims which propose otherwise."

According to FeedNavigator, Myers-Taylor filed the suit both independently and as a class-action so that others may join.

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