Claude Deroanne

Effect of the sowing date on physicochemical and fonctional properties of native starches extracted from European soft wheat (Triticum aestivum L.)

The influence of wheat sowing dates on the starch properties was evaluated during several growing seasons (2002 to 2005). Some European wheat varieties were sown at 2 distinct dates, cultivated in the same growing conditions and simultaneously harvested. The comparison of the 4 harvest seasons shows globally the same observations and the results of 2005 harvest are presented in this paper. A significant impact of the sowing date on the starch properties are measured for most of the studied varieties. An appropriate selection of the wheat variety and its sowing date could be valorized to emphasize starch properties researched in industrial end uses. Furthermore, these variations between the starch characteristics could lead to processing or end-products quality problems.

Influence of Nitrogen Fertilizer Treatments on Soft Wheat Starch Characteristics

Different nitrogen treatments were applied on winter wheat crops during several growing seasons (2002, 2003 and 2005). The starch was isolated and the impact of the nitrogen fertilization on the starch properties was evaluated. The comparison of the three harvest seasons shows globally the same observations. A significant impact of the N-fertilization on the grain yield and flour properties was measured for all studied varieties. The starch damages increased slightly with the N-doses but the other measured starch characteristics tended to be insensitive to applied N-fertilization. These results suggest that protein and starch accumulations in wheat grains are probably independent events.