Loose fruits and veg are cheaper

Asda charges 68p a kilo for loose bananas and £1.40 for a pack of ten. Although many customers believed the pack would be cheaper, buying ten loose bananas cost £1.20 – a saving of 20p.

At Sainsbury's, there are eight fruit in a £1.15 pack of 'Fairtrade Basics' bananas. Buying the same number loose would cost 96p – a saving of 19p.

Tesco sells an 'Eat Me' pack of five bananas for £1, while buying loose fruit would be 40p cheaper at 60p.

In Waitrose a pack of six 'Essential Fairtrade' bananas was £1.38, while buying six loose would cost 72p.

A Which? spokesman said: Supermarkets make it impossible to work out whether it's cheaper to buy bagged or loose fruit. We want them to show clear unit pricing – price per weight or item – so you can compare.