New ingredients could be made from 'waste'

Schemes recycling food waste will only make commercial sense if manufacturers can utilise all of the waste stream to create a range of different food ingredients or biofuels, according to the Institute of Food Research (IFR).

The IFR, which recently hosted an event exploring novel techniques for extracting maximum value from food waste streams, said rising landfill costs would force firms to find new markets for food waste.

However, this would only be viable if they found ways of using everything, said professor Keith Waldron, head of sustainability at IFR's food chain exploitation platform. "Ideally, you want to extract lower value ingredients such as thickeners, stabilisers and fibres, plus higher value bioactives. For example, waste onion peelings could create savoury flavourings, fibres for yogurts and other dairy products or low-calorie, zero-fat and non-starch instant thickening agents."

Brewers' spent grain was a particularly rich source material, and could be used to create stabilisers, protein-based components, fibres and bioethanol, he said.

A key challenge was stabilising waste streams to stop microbial deterioration, he added. "A Dutch firm called Provalor has tackled this by developing mobile facilities for extracting juice and colours from waste vegetables directly from the processing plants."

More funding for anaerobic digestion and sharp rises in landfill tax would help focus minds, added Waldron. "It's been difficult getting the economics to work when you're dealing with industries that have been based on cheap energy, but the opportunities are there. Look at whey. Twenty years ago we were still throwing it away."