The watchdog added that nearly half of all shoppers are now freezing food or cooking with leftovers to avoid waste.

More than 43 per cent of people are also checking the ‘use by’ or ‘best before’ dates more closely with 35 per cent ignoring the use by dates on food packets altogether.

The survey comes amid growing concern about rising food bills and the squeeze on disposable income. Which? claims that 36 per cent of people are dipping into their savings to pay for their groceries. The Daily Telegraph this week revealed a survey claiming that food prices will rise by nearly 20 per cent over the coming five years as global competition for meat and grain intensifies.

Richard Lloyd, Which? executive director, said: “Rocketing food prices are changing consumers’ habits, with more people helping themselves by cooking with leftovers and preparing smaller portions to avoid chucking expensive food into the bin.