Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2010
Publication Date: 10/1/2010
Citation: Chen, Y.R., Seabourn, B.W., Herald, T.J. and Tilley, M. 2010. Extensigraph dough preparation based on protein content and 10-g mixograph for limited sample size. AACC International Annual Meeting. Meeting Abstract 36. p. 10.
Technical Abstract: The Brabender extensigraph is one of several empirical rheological instruments used to determine dough extension characteristics to predict end-product qualities of wheat flour. The extensigraph method (AACCI 54-10) utilizes 450 g flour and a 50-g farinograph to estimate optimal mix time and water absorption requirements prior to testing. However, the official method does not always meet the needs of breeding programs that need to evaluate numerous experimental lines in a short period of time. Therefore, the objective of this study was to modify the official method in order to make the test more useful in terms of sample size, test speed, and objective dough preparation. For each sample tested, the 10-g mixograph was initially incorporated to estimate dough mixing time based on water absorption that was calculated from the formula: y = 1.67 x + 42.9 (where x = % flour protein content, 14% mb). Doughs for extensigraph testing were then prepared in a National 100-g pin mixer based on their respective 10-g mixograph peak time plus 30 sec and the calculated water absorption. As a result, overall flour sample size was reduced to approximately 110 g, compared to approximately 450 g for the standard method and dough preparation time was reduced to approximately 20 min, compared to 90 min for the standard method. This modified dough preparation step for the extensigraph method was highly correlated with data generated by the official AACCI 54-10 extensigraph method. The correlation coefficient (r) for 150 pairs of each of six extensigraph dough characteristics for 33 different tested wheat samples grown in the Great Plains, were 0.87 for energy (area under the curve), 0.88 for resistance-to-extension, 0.90 for maximum resistance-to-extension (Rmax), 0.82 for extensibility, 0.87 for ratio of resistance-to-extension to extensibility, and 0.89 for ratio of Rmax to extensibility. This rapid dough preparation method may be useful for breeding programs and may also be considered as an alternative to the standard method used by industry, research, and crop quality surveys.