Alter wheat dough viscoelasticity.

USDA-ARS researchers are looking to license a process that involves changing the mechanical properties of wheat dough used to make breads and noodles by using modified glutenin proteins. Wheat is the single greatest source of protein in the human diet. Wheat is also unique because the mixture of flour and water produces a dough with unusual physical properties, such as viscoelasticity.

The rheological properties of dough are attributable to many flour components, but the clearest association is with the storage proteins of the grain and flour. These proteins are divided into several families, of which the high molecular weight (HMW) glutenins correlate best with dough viscoelasticity and bread-making quality. Fundamental to dough functionality is the integrity of a highly cross-linked matrix formed by intermolecular disulfide linkages. Disrupting this network, such as by partial reduction, leads to a loss of dough functional properties. Hence, the number and placement of cysteine sites in the HMW glutenin termini have been thought to determine the viscoelastic properties of dough.

This ARS process encompasses producing dough, preferably wheat dough, with particular viscoelastic properties. Viscoelastic variation is achieved by using flour milled from seed containing non-natural HMW glutenin subunits. In particular, HMW glutenin subunits comprising a non-natural repetitive domain with repeat units that are not natural in number or synthetic in sequence are used by scientists to control the viscoelastic properties of dough. While controlling for termini and repeat sequence, modifying a repeat number may change dough properties such as viscoelasticity. Hence, researchers prefer that the repetitive domain be of a non-natural glutenin subunit length, preferably greater than natural length.

The technology also involves recombinant genes encoding HMW glutenin subunits, plants and seeds comprising such genes, as well as ways of making such plants by genetic engineering. The genes may encode natural repeat sequences recombined to encode proteins that have non-naturally long, repetitive domains. The genes may also contain non-synthetic or heterologous sequences that may be selected for preferential expression or secretion in a given host. Scientists tested doughs and other wheat products with modified viscoelastic properties and developed techniques for making such products.

Patent. 6,174,725. Altering wheat dough viscoelasticity with modified glutenins. Issued: Jan. 16, 2001. Inventor: Olin Anderson. Assigned to USDA. The patent covers the methods and compositions for producing dough, preferably wheat dough, with particular viscoelastic properties and the use of the dough in products such as breads and noodles. Viscoelastic variation is effected by using flour milled from seed containing non-natural HMW glutenin subunits.

Further information. Licensing: Mary Ann Gwozdz, USDA-ARS Office of Technology Transfer, 5601 Sunnyside Ave., Beltsville, MD 20705; phone: [phone]; fax: [phone]; email: [e-mail].