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Comparison of flour pasting characteristics using the micro-visco-amylo-graph, the visco-amylo-graph and
the RVA. C. E. PERRON (1), C. F. Morris (2), and P. Hucl (1). (1) Crop Development Centre,
University of Saskatchewan, Saskatoon, SK, Canada, S7N 5A8; (2) USDA, ARS, Western Wheat Quality
Lab, Pullman, WA, 99164.
The Brabender Visco-Amylo-Graph (VAG) has been used extensively
to measure the pasting properties of wheat flour and starch as well as for screening for enzyme activity.
However, the large sample size and time required to run a single test can be problematic in a wheat breeding
program where rapid, small-size testing is preferable. Using the Rapid Visco Analyzer (RVA), pasting
profiles of a 3-4g flour samples can be obtained in 20 min. Similarly, Brabender's
Micro-Visco-Amylo-Graph (microVAG) requires a sample size of 5-15g and full pasting profiles can be obtained in less than 20
min. The objective of this study was to compare the pasting profiles of a set of flour samples with a range of
starch properties and alpha-amylase activities using a microVAG (model 803220), a standard VAG PT-100
and an RVA-4. The samples were selected primarily from breeding yield trials grown in the Saskatoon area
of Canada in 1999, but also included a small number of Australian, Japanese and American waxy and
partial waxy wheat samples. The relative contribution of alpha-amylase activity and GBSS genotype to
starch pasting characteristics was considered through analysis of these components, as well as falling
number, starch damage and flour swelling volume.
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