Sainsbury's "needs to raise the bar on quality - in fresh produce it isn't where it needs to be", its head of technical for fresh foods Beth Hart told last month's Fruit Focus industry event.
"This means either the product spec (specification) isn't right or we haven't been meeting it," she added. "We need to decide with industry experts what a market-ready spec looks like," pointing out that 241 such specs are due to be revised or rewritten.
Explaining the context of the supermarket's new drive, Hart said: "The customer is very different today. They are complaining very publicly through social media."
Meanwhile, online shoppers "rely on others to make the call on quality and at the click of a button can shop somewhere else instead".
Giving strawberries as an example, she said: "They are our biggest-selling item in summer but a rotten strawberry can ruin a special occasion - it's the sort of thing people get in touch with us about in their hundreds. Yet we have a spec that permits a percentage of mouldy strawberries. In effect we are designing in disappointed customers, when we should be designing them out."
This can partly be achieved by making assessments less subjective, she explained. The supermarket's London headquarters already contains an "electronic tongue" and such scientific measures will become more widespread, she predicted
On strawberries, she added: "We know Brix levels aren't everything but how can we be quick and accurate in measuring other aspects of flavour?"