McDonald’s has started to use fresh beef in burgers sold at its US restaurants.

The fast-food chain is looking to improve food quality and ward off competition from premium burger chains.

Burgers containing fresh beef will be sold at most of McDonald’s 14,000 US restaurants by the end of June.

The move is part of bigger changes at McDonald’s, as new competitors, including burger chains such as Shake Shack, are using fresh ingredients to differentiate themselves.

As part of its turnaround efforts in recent years, McDonald’s has tweaked pricing and added to its menu. The fast-food chain has also ditched ingredients such as high fructose corn syrup in a bid to appeal to health-conscious customers.

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McDonald’s has been testing the appetite for burgers made from fresh beef for about a year. The premium quarter pounder and other offerings are now available at about 3,500 McDonald’s restaurants in the US, including in Miami, Orlando and Nashville.

These products are sold alongside existing burgers made using frozen meat.

Next month, fresh beef burgers will become available at restaurants in Los Angeles, Houston and San Francisco.

McDonald’s US president Chris Kempczinski said that offering fresh beef was the most significant change to the restaurant chain’s menu since it started offering all-day breakfast in 2015.

Chris Kempczinski said: “If it slows down the drive-through, that’s the critical part of our business. And so we just had to spend a lot of time really making sure that as we were cooking only when someone ordered, we’d figured out a way to do it that wasn’t going to slow down service time.”