What is Beta-glucan?

Introduction to Beta Glucan

Beta Glucan is a generic term for a number of non-starch polysaccharides occurring in plants and micro-organisms which contain glucose as the monomer, or building block.
They are characterised in that most are soluble or dispersible in water, and cannot be digested in the human stomach or intestine. They are therefore classified, from a nutritional labelling point of view, as fibres and, importantly, from a nutraceutical standpoint, they are soluble fibres.

The most well-known are those which occur in Cereal grains such as oats and barley, or in fungi and other micro-organisms. The most important Beta Glucan from a nutritional and ingredient standpoint is that derived from oat grain.

Oat Beta Glucan is scientifically classified as a (1,3),(1,4)-β-D-Glucan. The numbers in parentheses simply indicate the way the individual glucose monomers are linked together in the polymer beta glucan chain.

Oat Beta Glucan exists in the oat grain as a component of loose cell walls that contain the starch granules in the kernel, and as a major component of the sub-aleurone layer of the grain. The sub-aleurone layer is the really the first part of the oat bran, occurring next to the starchy endosperm that constitutes the flour when milled out and dried. Oat bran is therefore richer in Beta-Glucan than the whole oat grain, which also contains the flour part.

In the PromOat™ product, BioVelop has developed a precise, natural, stepwise procedure to loosen and concentrate the beta glucan within the sub-aleurone layer into a white powder containing up to 45% beta Glucan as analysed by International Standard methods.
PromOat™ is therefore a concentrated form of natural oat beta glucan which retains all of the natural characteristics of the beta glucan within the whole grain.

Oat Beta Glucan is hence the beneficial soluble fibre from the oat grain. It is precisely this soluble fibre component that is responsible for most of the very healthy properties of oat. Oat Beta Glucan is really the “essence of oat” from a health point of view. Oat Beta Glucan has been shown during 30 years of research to:

• effectively lower serum cholesterol in humans and thus promote cardiovascular health]
  
• to regulate glucose absorption from the intestine during digestion of sugary and starch rich foods, therefore lowering “GI” of a meal and protecting against obesity and type 2 diabetes
• as a true soluble fibre, it promotes excellent gut health, relieves constipation and offers long term protection against bowel diseases
• suppress appetite, because it forms a thick, viscous solution in the human gut, causing a feeling of fullness and satiation

Research has also established that to work in these areas, the beta glucan should not be degraded during concentration or oat processing and that it should be readily soluble. The PromOat™ ingredient fulfils all of these criteria and is therefore the Oat Beta Glucan of choice for the food manufacturer. More specific information about Health Aspects of PromOat™ can be found on this website.

Other Beta Glucan Products
There are two major types of beta glucans in the market: cereal-derived (oat) and micro-organism-derived (mainly fungal).

The Beta Glucans derived from Fungal Micro-organisms are scientifically classified as (1,3),(1,6)-β-D-Glucan, or (1,3)-β-D-Glucan. These are chemically different molecules to oat beta glucan and are therefore, importantly, different products. They are generally less-soluble and tend to be marketed on their “immune-boosting properties”. These properties are a consequence of their chemical structure and their micro-organism origin. Because of the source (fungal cell wall, yeast etc), and the methods employed to concentrate and isolate the materials, they are very expensive products and lack the “popular appeal and healthy image” of oats.

Oat Beta Glucans are currently available in two broad types of product: Insoluble bran and Soluble.

Insoluble bran products consist primarily of oat bran which has been purified by extensive milling and/or extraction with organic solvents. In any case the end-product contains low levels of beta glucans (12 to 22%), high fibre and starch contents. Therefore, it is still a bran-type (fibrous) product which has several limitations in food applications, hence the relatively low price and market penetration. The largest drawbacks to such a product is the “gritty aftertaste” due to the insoluble milled bran components, the settling out and sedimentation of these components in liquid preparations, and to a relatively strong and distinctive oat cereal taste

Soluble products can be produced from a variety of processes and are much more interesting from the application point of view. For example they may have functionalities which are quite ideal for beverages, baked goods, dairy products, etc. The level of beta glucan may vary from 1 to 70%, but without any exception the price per kilo of beta glucan has been far too high and only affordable in rather niche areas.

PromOat™ is based on a soluble fibre. It can be produced with very high levels of beta glucans, but it can be marketed at considerably lower price.

Up to the present date, Oat beta glucan have been sold into neutraceutical, functional food and cosmetic markets whereas microbial-derived beta glucans almost exclusively go into the high end neutraceutical and cosmetics market.

PromOat™ will change this, being a highly functional, low-taste, white Oat Beta Glucan concentrate, with a realistic price for food producers.