Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Oral Communication Abstract - S2f

b-GLUCAN AND TOCOLS IN SMALL GRAIN CEREALS FOR THE DEVELOPMENT OF FUNCTIONAL FOODS

FINOCCHIARO F.*, FERRARI B.*, CAVALLERO A.*, FARES C.**, DI FONZO N.**, GIANINETTI A.*, STANCA A.M.*

Istituto Sperimentale per la Cerealicoltura

*) Sezione di Fiorenzuola (PC)

**) Sezione di Foggia

functional foods, barley, b-glucan, tocol

We are in a new era in the fields of food science and nutrition with an increasing emphasis on the interaction of foods and medicine. The practical results of this area of study are known as “functional foods”, which involves food components, as essential nutrients needed to maintain optimum health, and as non-nutritional components which contribute to the prevention of chronic illnesses. “Functional foods” may be defined as any food, in a natural or processed form, which contains, in addition to its nutritional role, components that favour the good health, physical capacity and the mental health of an individual.

The abundant evidence regarding the role that nutritional factors play in maintaining health, and also the role of diet in the occurrence of ten of the major causes of death (including hearth disease, cancer, stroke, diabetes, arteriosclerosis, liver disease), have contributed to the present dietary “revolution” and to the interest in functional foods.

Small grain cereals are important sources of many nutrients including dietary fibre, resistant starch, oligosaccharides, trace minerals, vitamins and other compounds of interest in disease prevention, including antioxidants. Barley is the main cereal grain for the development of functional foods. In fact it contains two classes of compounds of strong nutritional interest: tocols (vitamin E) and b-glucan (dietary fibre). Dietary fibre is defined as the edible parts of plants or analogous carbohydrates that are resistant to digestion and absorption in the human small intestine. Dietary fibre promotes beneficial physiological effects including laxation, and/or blood cholesterol attenuation, and/or blood glucose attenuation.

In our Institute two varieties of durum wheat, bread wheat, T. dicoccum and barley have been grown in different italian environments to evaluate accumulation of b-glucan and tocols. Variability has been found among species and varieties for the different tocols isomers.

In a second experiment barley flour from whole naked grain and two b-glucan enriched fractions, a sieved fraction and a water-extracted fraction, were produced and mixed with bread wheat flour, for bread-making quality evaluation. Bread was baked in a pilot plant and analysed for sensory properties, proximate composition and b-glucan content.

Eight adults were fed test meals of each of the four breads, containing the same amounts of available carbohydrates, and glycemic indices calculated from finger-prick capillary blood samples. A linear decrease in glycemic index was found for increasing b-glucan content. This research confirms the effectiveness of viscous b-glucan in reducing postprandial blood glucose levels, even in foods with high glycemic index. The enrichment technique, and water extraction/freeze-drying technique, could enable the use of barley as a source of high-value fibre for reducing the glycemic index of traditional wheat-based food such as bread, without negatively affecting their sensory characteristics.

We are in a new era in the fields of food science and nutrition with an increasing emphasis on the interaction of foods and medicine. The practical results of this area of study are known as “functional foods”, which involves food components, as essential nutrients needed to maintain optimum health, and as non-nutritional components which contribute to the prevention or the delay of chronic illnesses. “Functional foods” may be defined as any food, in a natural or processed form, which contains, in addition to its nutritional components, components that favor the good health, physical capacity and the mental health of an individual.