Exploiting Grain Bioactivity for Improved Nutrition and Health

Kaisa Poutanen

VTT Technical Research Centre of Finland, POB 1500, FI-02044 VTT, Finland

Intake of both cereal dietary fibre and whole grain has been shown to protect against

rapidly expanding chronic diseases such as cardiovascular disease and type 2 diabetes.

The mechanisms are as yet not known, but the protection is suggested to be due to the

concerted action of dietary fibre and various bioactive compounds such as lignans,

phenolic acids, alkylresorcinols, phytosterols, folates, tocopherols and tocotrienols, other

vitamins and minerals. Being concentrated in the outer layers of the grain, these

compounds are often removed in current milling processes, optimised to deliver products

made of refined grains.

Foods should be made available to deliver more grain fibre and outer layers of the grains,

while also addressing the consumer expectations of palatability and convenience. This

demands for new ingredients high in grain phytochemicals and with good technological

properties. The natural diversity in grains offers a good basis for tailored fractionation

and bioprocessing. The grain chain from plant breeding and crop selection should take

into account the nutritional quality criteria set by the end-use. This was the approach in

the EU integrated project HEALTHGRAIN running in 2005-2010 (www.healthgrain.org),

which addressed the whole grain chain to provide consumers with healthy grain-based

foods and ingredients (Poutanen et al 2008). It included studies of consumer

expectations, development of a biotechnology toolbox for plant breeding, development of

wet and dry milling and novel bioprocessing technologies for grain processing, studies of

mechanisms behind the metabolic merits of foods in a series of in vitro, animal and

human studies, and identification of health-relevant cereal food criteria.

The HEALTHGRAIN diversity screen analysed one hundred and fifty bread wheat lines and

50 other lines of small-grain cereals (spelt, durum wheat, Triticum monococcum, Triticum

dicoccum, oats, rye, and barley), selected for diversity in their geographical origin, age,

and characteristics. They were grown on a single site in Hungary, and analysed for a

range of phytochemicals (tocols, sterols, phenolic acids, folates, alkylresorcinols) and

fibre components that are considered to potentially have health benefits. The results

showed that it is possible to identify lines with high levels of phytochemicals and dietary

fibre, and which also show good yield and processing quality (Ward et al 2009). In the

next phase also the effect of environment was studied in a smaller subset of samples

grown in four countries in two years (Shewry et al 2010).

Having the grain raw material rich in the above mentioned nutritionally interesting

compounds, it is important to process it so as to maintain the high nutritional value.

Milling processing can be tuned for production of new ingredients (Hemery et al 2007).

This necessitates knowledge about distribution of the bioactive compounds in the grain

(Barron et al 2007, Hemery et al 2009). Wheat aleurone is an example of novel wheat

grain fraction with high levels of potentially health-promoting compounds. It has also

been shown that the way of processing influences the bioaccessibility and bioavailability

of f.ex. phenolic compounds in the cereal food (Mateo Anson et al 2009). It is thus

important to consider cereal product quality as an interplay of the raw material and

process-induced changes.

NJF Report Vol 6 No 2 Year 2010

References

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(Triticum aestivum L.) grain and their carbohydrate and phenolic acid composition.

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Hemery, Y.; Rouau, X.; Lullien-Pellerin, V.; Barron, C.; Abecassis, J. Dry processes to

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Acknowledgment

The study is financially supported by the European Commission in the Communities 6th

Framework Programme, Project HEALTHGRAIN (FOOD-CT-2005-514008).

NJF Report Vol 6 No 2 Year 2010