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The role of gluten and its components in durum semolina dough viscoelastic properties. N. M.
EDWARDS (1), M. G. Scanlon (2), S. Cenkowski (3), and J. E. Dexter (1). (1) Canadian Grain
Commission, Winnipeg, Canada; (2) Dept. Food Sci., University of Manitoba, Winnipeg, Canada; (3) Dept.
Biosys. Eng., University of Manitoba, Winnipeg, Canada.
Gluten was isolated from three durum wheat cultivars of weak,
intermediate and strong dough strength. Gluten was further fractionated into gliadin, total glutenin and
HMW and LMW glutenin. Base semolina (2g) was enriched with 40 mg protein of each fraction, except
HMW glutenin where 20 mg was used because of lack of material. Doughs were prepared in a 2g
mixograph at 50 percent absorption and were subjected to creep testing over 10,000 s with stress applied in
the linear viscoelastic region. A six element Burgers model satisfactorily described the creep compliance
data. Addition of gluten from the intermediate and strong cultivars to the base semolina resulted in mixing
curves typical of stronger doughs and reduced base semolina creep compliance, but gluten from the weak
cultivar had little effect on dough mixing strength or compliance. Addition of gliadin weakened mixing
curves and increased compliance relative to the base semolina, with no differences seen among cultivars.
Glutenin and LMW glutenin enrichment increased mixing strength and reduced compliance, ranking
according to the mixing strength of the donor cultivar. Rankings persisted when considering only the
retarded elastic compliance. HMW glutenin increased dough strength and reduced compliance, but
differences were not seen between cultivars.
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