Grape extract eyed for use in health food and cosmetics

New Zealand winemakers nervously watching the growing glut of wines across the Tasman are taking an interest in a novel effort at diversification in Marlborough.

The Grape Seed Extract Company, based in Blenheim, has moved to recycle the waste product from wineries into an antioxidant extracted using a non-chemical method.

Antioxidants in tannins from pine bark and grape seeds were identified years ago by a scientist at Industrial Research in Lower Hutt, Dr Lai Yeap Foo, as having potential applications as antioxidants in health foods.

The Blenheim company has developed the means to a stable extract that looks likely to make grape seed extract a more common candidate for use in functional food and cosmetic products, research director Glenn Vile said at a food show in Geneva.

"Functional foods and cosmetics are the way things are going," Dr Vile told a food science news website, Nutraingredients.com. "The days are gone when you just add vitamin E to a product for antioxidant properties. People want specifics."

He said the new extract, marketed as Vinanza Gold, was different from others because it was extracted using water rather than ethanol.

It had a mixture of low and high molecular weight antioxidant compounds, in the same proportion as found naturally in grape seeds.

The company has contracts to take the marc - the leftover parts of the fruit after the juice has been extracted for wine - but uses only sauvignon blanc grapes. Sampling of the antioxidant content of several different cultivars showed a specific sauvignon blanc grape had twice the antioxidant content of other grapes.

Dr Vile said the company's theory was that the high level of ultraviolet radiation in Marlborough stressed the vines and they produced extra antioxidant while adapting.

Tests have shown that 7 to 9 per cent of the grape seed is made up of antioxidant compounds, and research on other varieties and fruit grown in other locations suggested the norm was an average of only 3 to 4 per cent. The antioxidants were stable: tests for the ORAC value (a standard measure) of its extracts before and after extrusion into breakfast cereal or baking into bread at 180C showed antioxidant activity remained at 95 and 90 per cent respectively.

This stability suited the extracts to use in food, and Dr Vile said his team was working with a cereal company to develop a muesli using the natural extract to deliver the same antioxidant levels in one serving as in a 75g bunch of grapes.

The cereal will be launched in New Zealand in October. Other trials are with a beverage company, a biscuit manufacturer and a baking company.

The company is also looking at exporting to Japan and Europe, and has received a Government research grant to assess the precise health benefits of its grape seed extract for heart or sports health.

- NZPA