Food inflation now stands at 2.9 per cent, according to figures from Kantar Worldpanel, outpacing the UK's overall rate of inflation.
The general rate of inflation spiked to 2.7 per cent in April, up from the 2.3 per cent rate recorded the month before.
The higher prices have been boosting supermarket sales figures, with overall sales up by 3.8 per cent year-on-year for the 12 weeks ending 21 May.
This was the grocery sector's best set of sales figures since September 2013.
German discounters Aldi and Lidl grew at their fastest rate for two years, bagging a combined market share of 12 per cent. Kantar said 62 per cent of the UK shopped in either an Aldi or a Lidl over the past three months.
Josh Mahony, market analyst at IG, said it was "no surprise" that Lidl and Aldi were growing market share.
"UK shoppers are increasingly heading to the discounters in a bid to overcome the incessant rise in food prices, which are far outstripping the wide inflation picture," he said.
Richard Chamberlain, analyst at RBC Capital Markets, said there was a "genuine shift of traffic to discount formats", rather than just a seasonal change, due to "subdued wage growth and rising inflation pressures".
Morrisons put in the best performance of the "Big Four" supermarkets, growing its sales by 1.9 per cent over the period.
"Consumers are starting to feel the pinch as prices continue to rise, with the average household spending an additional £27 on groceries during the past 12 weeks," said Chris Hayward, consumer specialist at Kantar Worldpanel.
"That may not seem like much, but if inflation continues at its current rate over the course of a year that would mean an extra £119 spent on groceries per household."