Amount and Size Distribution of Monomeric and Polymeric Proteins in the Grain of Organically Produced Wheat

Abstract

ABSTRACTIn the present study, we evaluated 444 organically grown wheat genotypes for the amount and size distribution of polymeric proteins by size‐exclusion HPLC. The investigated genotypes were divided into six genotype groups—selection, spelt, old cultivar, primitive, landrace, and cultivar—and these were grown in four different locations, namely, Alnarp, Bohuslän, Gotland, and Uppsala in Sweden. The results showed that the percentage of unextractable polymeric proteins in total polymeric proteins (%UPP) and percentage of large unextractable polymeric proteins in total polymeric proteins were higher in the cultivar group as compared with the rest of the investigated genotype groups. The amounts of total extractable polymeric proteins (TOTE) and total unextractable polymeric proteins were low in cultivars and selections, respectively. Spring wheat grain was found to have a significantly higher amount of all protein fractions as compared with winter wheat. The genotype Kenya was found to belong to both groups of the 20 genotypes with the highest TOTE and %UPP. Thus, the genotype Kenya might be of relevance for consumption and future breeding to improve the breadmaking quality of organically produced wheat.