Sainsbury's is preparing to phase out brown eggs from its own-brand ranges as part of a major push to reduce emissions across its business. The supermarket giant plans to switch to white-shell eggs after studies found they have a significantly lower carbon footprint than their brown counterparts. The retailer believes the move will help it work towards its environmental targets, which include reaching net zero in its own operations by 2035 and across its wider supply chain by 2050.

Sainsbury's said white eggs generate 12.7% fewer emissions because the hens that lay them are typically smaller and require less feed, The Telegraph reports. The company said this helps to "indirectly reduce demand on land and water used to grow feed crops, as well as the amount of manure produced". The move is one of the most visible sustainability changes shoppers are likely to notice in stores, with egg colour set to change despite there being little nutritional difference between brown and white varieties.

The retailer also argues the switch could improve animal welfare standards. Hens bred to lay white eggs are considered less likely to suffer from feather pecking, according to Sainsbury's. In its latest annual report, the supermarket said it was "making progress" with plans to move its own-brand egg ranges to white shells.

However, increasing supplies of white eggs could prove difficult. While white eggs are common in countries such as the United States, where they account for around three-quarters of eggs consumed, British shoppers have traditionally preferred brown eggs. The British Egg Industry Council estimates that hens laying white eggs currently make up just 15% of the UK's flock, reflecting decades of breeding aimed at meeting consumer demand for brown-shelled eggs.

Any large-scale shift in consumer buying habits could therefore require suppliers to gradually adjust production over several years. Brown eggs became dominant in Britain after many shoppers came to believe they were healthier or more natural than white eggs. Claims that white eggs had been bleached also helped fuel their popularity, despite those suggestions being false.

Before that, white eggs were a familiar sight on supermarket shelves throughout much of the 20th century. Today, many white eggs produced in the UK are supplied to restaurants and catering businesses rather than sold directly to consumers. Breeds such as the White Leghorn, which originated in Italy, are among the best-known white egg layers.

A Sainsbury's spokesman said: "White eggs have the same delicious taste and nutritional benefits as their brown counterparts, but result in lower emissions and better welfare outcomes for the hens that lay them.

"We know Brits love their eggs and, as we work with suppliers to transition all our own brand to white shells, they can now enjoy them knowing they are better for the environment and the hens."

The egg shake-up is the latest in a string of measures introduced by Sainsbury's as it attempts to reduce its environmental impact.

In 2023, the retailer switched minced beef from plastic trays to vacuum-packed packaging in a bid to cut plastic use.

The move sparked complaints from some customers who claimed the packaging affected the quality of the meat, although Sainsbury's has continued with the approach and rival supermarkets have since introduced similar packaging.

The company also revealed in 2023 that it had begun sending cattle for beef production earlier than normal as part of efforts to lower emissions.

The latest changes underline the growing pressure on major supermarkets to reduce their environmental footprint while balancing customer preferences and supply-chain demands.