Leatherhead to identify bioactives from waste

While most people are aware that fruit and vegetables are good for your health - a connection that has been borne out by epidemiological studies. While in some cases the exact component has been identified - such as lycopene in tomatoes and glucosinolates in brassica vegetables - in many others it remains a mystery.

UK-based Leatherhead Food International is aiming to identify plant foods containing compounds that have a specified biological activity, and find alternative uses for waste materials. The findings should give participating companies a head start in an area that looks set to figure large in the food industry's future.

At present, by-products from food processing like potato peel or peanut skins are commonly used by the animal nutrition industry. Project co-ordinator Rosemarie Bramble told NutraIngredients.com that the UK government has been looking into more effective ways to use such waste, and has shown an interest in the upcoming research.

Nutritional use of waste matter is a model that has been used in other parts of the world. For instance, New Zealand is particularly know for exploiting the by-products of its agricultural industries for nutritional uses.

Researchers at Cornell University in the US developed the technology to derive powerful phenolic compounds from apple peel, now licensed to Health Sciences Group; Singaporean scientists reported in Food Chemistry​ this year (Vol. 97, pp. 277-284) that residues from star fruit, a waste product from the juicing process, is a rich source of extractable antioxidants.

A Spanish-German study in the same journal also suggested that waste products from processing of fruit and vegetables offer a practical and economic source of potent antioxidants that could replace synthetic preservatives. In this case golden rod, red beet, asparagus, artichoke, and apple were seen to yield the highest phenolic content with polar solvents like water and methanol.

Leatherhead's approach, however, is to return to square one and no assume any prior knowledge of bioactive compounds. It is seeking companies to contribute funding and propose two samples for analysis - be they whole plant foods like fruits, vegetables, seeds or herbs, or waste peel or pulp.

The researchers will prepare activity-guided fractionation which, as well as identifying the biological compounds, more easily identify synergistic effects.

The first step will be to prepare simple extracts in a range of buffers/solvents, and to look at the effect of simple food processing and/or an in vitro digestion step.

The extracts will then be tested for their ability to affect a defined biologically-relevant parameter, like antioxidant activity or glucose uptake. Where bioactivity is seen, the extract will be further fractioned using chemical and biochemical methods for a purer preparation of the compound.

The final stage will be a preliminary chemical characterization of the type of compound with the bioactivity.

Bramble said that the findings will be shared between all participating companies, who will have the right to apply them to their own product development. The findings will not be publicly available.

Leatherhead is aiming to attract between ten and 15 companies to the product, who will share the £200,000 costs between them. It is hoped that the project will get underway in March 2007.

More information on the project is available from project coordinator Rosemarie Bramble​, tel: +44 1372 822358.​