The story of Bakkover

‘Knox™ significantly reduces in-store waste levels’

Knox significantly reduces in-store waste levels

Many years ago, Bakkavor – the leading provider of fresh prepared food (FPF) in the UK – was the first Rijk Zwaan partner to conduct tests with Knox™ lettuce. Those tests demonstrated the shelf life benefit, and the customer is now incorporating Knox varieties into its entire range. “We believe it delivers opportunities and benefits to consumers, retailers and our factories,” says Clare Foy, Customer Produce Manager at Bakkavor.

Important to our business

The story on the Bakkavor website outlines why the Knox trait is so relevant: “Cos lettuce is very important to our business. It’s sweet, it has a fantastic texture, it’s the main constituent of the iconic Caesar Salad and we use over 1 million kilos of it each year. But while popular, the lettuce had historically been problematic due to the fact it tended to discolour on cut surfaces (a process also known as pinking). This led to customer complaints, reduced shelf life and levels of waste.”

Knox significantly reduces in-store waste levels

Delayed discolouration

“Still, there was nothing anyone could do about this, right? Wrong. We have a long-established relationship with international vegetable breeding company Rijk Zwaan and challenged its team to improve the shelf life of fresh- cut salad leaves by developing a non-discolouring Cos lettuce. Rijk Zwaan was up for the challenge and managed to identify a natural gene that confers delayed cut-surface discolouration.”

Increases shelf life by at least two days

“When the first prototype lettuces featuring this new trait were produced, Bakkavor was Rijk Zwaan’s first partner to run tests and prove the shelf life benefit, with our data indicating that the Knox trait could increase shelf life by at least two days. Our commercial trials were an instant success, with in-store waste levels and customer complaints reducing significantly. Since then, we’ve continued the project at pace.”

Rolling out the project

“So, in addition to rolling the project out to the point where we’re maintaining supply of Knox Cos all year round, we’ve become the first food producer to commercially grow it in Spain,” states Bakkavor on its website.

Bauke van Lenteren

60 lettuce varieties with the Knox trait

Bauke van Lenteren, Marketing Specialist Leafies at Rijk Zwaan, explains that varieties with the Knox trait are available for all lettuce types: “At our recent online Global Open Field e-vent we presented 60 commercial and new varieties with this trait, including some outstanding iceberg lettuce varieties. Bakkavor is currently trialling our green Knox Salanova® crispy types such as Excerno RZ and Excuria RZ. Bakkavor is an important partner for Rijk Zwaan, and we’re continuing to innovate together for a healthy future.”

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