Newsflash: Pre-washing bagged salad leaves doesn’t enhance their quality.

It actually reduces shelf life, increases cost, and to be safe consumers should wash a pre-washed product anyway, highlighted in recent years by product recalls on pre-washed bagged salad involving E. coli. In 2013, Sainsbury’s recalled all its own-brand bagged watercress because of an E. coli outbreak that made 18 people ill.

In her book ‘Swallow This: Serving Up The Food Industry’s Darkest Secrets’ food expert Joanna Blythman suggests that the safest way to eat pre-packed salad is to either re-wash it yourself or buy it unprepared and then wash it.

washed salad

This is because the water that pre-washed salad is “washed” in often includes powdered or liquid fruit acids to inhibit bacterial growth. Disinfectant (chlorine) is added to keep the water clean and kill off bugs but many are resistant to the chemicals, which reduces the nutritional value of the food. Furthermore, the same tank of water can be used for up to eight hours at a time which reduces the sanitising effect.

Salad requires plenty of water to grow and if that water is contaminated by bugs such as listeria or salmonella, they can live in salad cells until eaten – and washing it doesn’t make a difference.

Feeling worried yet?

If not, let’s hear from Professor Hugh Pennington, emeritus professor of bacteriology at the University of Aberdeen. Professor Pennington has claimed that certain types of bacteria found in pre-packed salad bags could almost be impossible to kill.

How’s that tasty pre-washed salad looking?

What pre-washing salad does do is offer the consumer a very obvious perception of convenience, which is a key attraction in the bagged salad market.

However, what price are you willing to pay for convenience?

Let’s talk