An integrated approach to improve bread nutritional quality
Résumé
A post-genomic program was initiated to study the potential improvement of the micronutrient content of wheat and their bioavailability in derived food products. To do so we chose an integrated approach most adapted to the European market and consumers. We were interested in increasing the overall nutritional value of wheat and wheat-based products by a synergy between plant breeding, production schemes and adapted transformation processes. The originality was to take each and every step within the cereal chain into consideration. The aimed targets were the vitamin (B especially) and mineral concentration (Mg) and bioaccessibility. The first objective of this inter-disciplinary project was to explore the genetic basis of targeted nutritional wheat traits. Despite the impact of growing conditions on micro-nutrient content we showed there is a strong potential for nutritional trait improvement in European wheat by traditional breeding. Rare alleles have been identified by systematic study of germplasm diversity. They are now used in the genetic identification of relevant molecular markers, necessary for efficient introduction of nutritionally correlated chromosome segments in a genetic base of good agronomic and end-use criteria. Wheat is rarely consumed as whole grain products and most of the time goes through fractionation steps (e.g. milling) and transformation processes (e.g. bread-making) Variability in cereal raw material micro-nutrients impact on the nutritional density of final products. A strong interaction between process and variety was observed. New fractionation processes, based on the mechanical properties of the aleurone layer, and product concepts have been derived from this understanding.