Cereal Chem. 73 (1):123-130 |
Effects of Nitrogen Fertilization and Maturation Conditions on Protein Aggregates and on the Breadmaking Quality of Soissons, a Common Wheat Cultivar (1).
Yong-Qing Jia (2), Veronique Masbou (3), Thierry Aussenac (3,4), Jean-Luc Fabre (3), and Philippe Debaeke (2). (1) Research supported by a grant from Conseil Régional Midi-Pyrénées, Contract RECH 92086608. (2) Laboratoire de Physiologie Végétale E.S.A.Purpan. 75 Voie du Toec 31076 Toulouse Cedex France. (3) Station díAgronomie I.N.R.A. BP27 31326 Castanet Tolosan Cedex France. (4) Corresponding author. Fax: 6115 30 00. Accepted September 13, 1995. Copyright 1996 by the American Association of Cereal Chemists, Inc.
Formation of storage proteins and their aggregation in response to available nitrogen and maturation conditions were investigated for the French wheat cultivar Soissons. N-fertilization level greatly influences the accumulation of the different classes of storage and metabolic proteins by modifying the relative composition of the protein pool, which can be expressed by a decrease of the ratio of glutenins to gliadins and also by variations in baking strength. Changes in glutenin content, high molecular weight glutenin subunits (HMW-GS), and aggregates were monitored by nitrogen determination, sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis, size-exclusion high-performance liquid chromatography, and reversed-phase high-performance liquid chromatography. Whereas the composition in HMW-GS remained unchanged, the aggregation level of glutenic polymers developed differently depending on the maturation conditions. These aggregation variations are discussed in connection with the specific contribution of some HMW-GS to the formation of both soluble and insoluble SDS-glutenic aggregates and also with baking strength response.