Fractionation technology developed by VTT increases diverse uses of oats
VTT Technical Research Centre of Finland has, in collaboration with Agrifood Research Finland (MTT), developed a technology to efficiently separate the health-promoting beta-glucan from oats. The technology can also be used to produce high-quality oat protein, starch and lipid fractions. The new fractions increase the possibilities to use oats in the food, cosmetics and pharmaceutical industries.
The blood cholesterol lowering effects of beta-glucan, the soluble oat fibre,
is well known. Still, the usage of β-glucans in industry is relatively low.
One reason for this is the lack of β-glucan-rich fractions that are feasible
in food applications.
The dry processing method developed by VTT is based on fractionation of fat-free oats using milling and classification technology. In the first processing stage, the fat is removed form oats using supercritical extraction technology developed by MTT. This technology is previously used to remove pesticides from rice and to extract berry oils from seeds. Milling and classifications of this material results in three types of oat fractions: The main product is a coarse, light-coloured bran, with a beta-glucan content of approximately 40 per cent; defatted starch-protein flour; and small amounts of nearly white, extremely light fraction with a beta-glucan content of over 50 per cent. Traditionally, dry fractionation methods for oats have resulted in oat bran concentrates with only slightly over 20 per cent beta-glucan content.
The developed technology has several benefits. As a dry process, it is economically far more feasible than wet processes. Until now, the wet processes have been the only option for production of fractions with such high beta-glucan content. With the used extraction method oat fats can be efficiently removed, increasing the self-life of the fractions and decreasing the well-known rancidity problems often related to oat products. Due to the gentle processing method, both the beta-glucans and other bioactive compounds in oats remain in their natural state.
Oat fractions produced with the new method are well-suited, for instance, for beverages, dairy applications, baking, snack products and fermented products. The cosmetics and pharmaceutical industries can also utilise them.
VTT has developed special know-how in dry milling and classification technology of plant-based food raw materials for years. The dry milling method is suitable for processing of versatile plant raw materials and plant-based side-streams. The technology offers the opportunity to isolate fractions from plant raw materials that can, for instance, be used to deliver improved taste and additional health benefits into products.
The development of oat fractionation technology has been carried out during years 2004-2007 and has been financed by the Ministry of Forestry and Agriculture. The management group of the research project included several Finnish companies.
Approximately 25 million tonnes of oats is produced annually worldwide.
Half of the production is used as cattle feed and only a quarter for food, seed and other products. Due to the health-promoting effects of soluble beta-glucan fibre in oats, oats have a string position as a raw material for functional foods.