In a bid to find out which supermarket delivers the freshest food, consumer group Which? deployed mystery shoppers to order 29 fresh groceries from locations across the UK.

Asda, Morrisons, Ocado, Sainsbury’s, Tesco and Waitrose were investigated over a two-week period, with 2,000 perishable goods ordered and delivered. Asda was crowned “the freshest supermarket”, with perishable items that had use-by dates averaging 11 days from delivery.

Additionally, five shoppers received beef mince with 18 days or more before it went off, and a pack of cod fillets had seven days.

Waitrose delivered the least fresh groceries, with use-by dates averaging just 7.7 days. The high-end supermarket had the lowest averages for scones, bread, fresh pasta sauce, houmous, fresh tagliatelle and pork sausages.

During the test period, one shopper recieved beef mince with just 1.2 days left before it went off, and another got chicken thighs with 1.6 days remaining.

Waitrose responded to the survey: “We are committed to offering the freshest and highest quality products, reflected in our growing online grocery sales. And in response to increasing customer demand for products with simpler ingredients, we have removed preservatives from some of the items in this analysis where they are common, including our houmous.

“Our online grocery pickers are trained to choose the longest dated products they can, and our most recent customer survey showed that the vast majority of our online customers rated the shelf life of our products as good or excellent.”

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The consumer group also looked at substituted items, and the impact this had on shoppers. It found seven items were delivered on their use-by or best-before date, including a substituted raspberry trifle from Morrisons that had just under four hours left until it expired and a toffee sundae from Tesco with around 13 hours left.

“Having to dig straight into dessert may seem like a trifling issue, unless it was bought with future dinner plans in mind,” joked Hannah Walsh, senior researcher for Which?

However, many shoppers shared numerous examples of food that arrived damaged or looking past its best, despite being within its use-by or best-before date.

Walsh added: “One pack of M&S basil from Ocado was limp and wilted. Multiple people reported freshness concerns about pre-cut carrot batons from several supermarkets, noting carrots that looked ‘slimy’, ‘wet’ or ‘manky’.”

There was also reports of packaging leaking and even open packaging. These issues were reported on a wide variety of items, including a curry ready meal, a toffee sundae, mozzarella, fromage frais pots, bread and milk.

The consumer body advised shoppers to take time unpacking products at home, with refunds available even once items have been delivered.