Some meat, yoghurt and vegetables are among items that have doubled in price compared to a year ago, new figures show.
Which? urged Prime Minister Rishi Sunak to intervene on behalf of struggling consumers as its latest data shows food inflation remaining at “shockingly high levels”.
The figures come ahead of Tuesday’s Downing Street “Farm to Fork Summit”, bringing together farmers’ representatives and food and retail trade bodies along with supermarket chiefs to talk about the Government’s goal of boosting cooperation across the supply chain, the sector’s resilience and rampant food inflation.
The Which? analysis of April prices on more than 26,000 food and drink products at Aldi, Asda, Lidl, Morrisons, Ocado, Sainsbury’s, Tesco and Waitrose found inflation in categories that have previously seen the highest rises – including milk, butters and spreads and bakery items – has eased slightly.
Overall inflation has also started to ease slightly, from 17.2% in March to 17.1% to the end of April, according to the tracker.
However other essential food groups like meat, fish and vegetables have continued to rise month on month.
A pack of four brown onions at Morrisons went from 65p to £1.24, a 90.8% rise over 12 months.
Also at Morrisons, Lancashire Farm Natural Bio Yoghurt 1kg went up from £1.18 to £2.18 over the year, a rise of 85.3%.
Other food categories where inflation continued to rise month on month included juice, chocolate, water, fish, chilled ready meals and cheese.
Which? found Aberdoyle Dairies Natural Cottage Cheese 300g at Lidl had gone from an average of 67p in 2022 to £1.34 this year, a difference of 100.9%.
At Tesco, a 260g pack of own-brand salmon tails rose 51.4% from £3 to £4.54.
Supermarket own-label budget items were up 25% in April on 12 months ago, demonstrating how low-income shoppers are being hit hard by soaring inflation.
Branded goods, meanwhile, showed no change on March, staying at 13.8% higher than last April, while regular own-brand food and premium own-brand food inflation decreased slightly.
Which? called on the Prime Minister to challenge supermarket chiefs to take urgent action to help consumers cope with “rampant” food price increases by ensuring that smaller convenience stores stocked a range of essential budget lines that support a healthy diet, especially in areas where they are most needed.
It has also called for supermarkets to commit to clearer unit pricing, especially on promotions and loyalty card offers, so that people can easily work out which products offer the best value.
Sue Davies, Which? head of food policy, said: “It’s very alarming to see products such as meat, cheese and vegetables that people rely on still rapidly soaring in price.
“As the Prime Minister gathers supermarket bosses today to discuss the problem of inflation, we urge him to ask supermarkets to commit to do much more, including stocking budget lines in convenience stores to ensure easy access to basic, affordable food ranges that support a healthy diet, particularly in areas where people are most in need.
“Supermarkets must also provide transparent pricing so people can easily work out which products offer the best value.”
Rebecca Tobi, senior business and investor engagement manager at The Food Foundation, said: “We know that the current food price crisis is causing a great many households to cut back on essentials.
“With levels of food poverty among children having doubled in the year to January 2023, government and businesses must act urgently to ensure that everyone can afford and access healthy essentials like fruit and vegetables.
“If not, we will be seeing the long-term health and economic consequences of the cost of living crisis playing out for years to come.”