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ARS Home » Pacific West Area » Pendleton, Oregon » Columbia Plateau Conservation Research Center » Research » Publications at this Location » Publication #221606

Title: Segregation of Soft White Wheat by Density for Improved Quality

Author
item Siemens, Mark
item JONES, DEB - GILLIAM CO GRAIN QUALITY

Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/14/2008
Publication Date: 5/1/2008
Citation: Siemens, M.C. and D.F. Jones. 2008. Segregation of Soft White Wheat by Density for Improved Quality. Transactions of the ASABE 51(3):1035-1047

Interpretive Summary: Buyers of wheat desire grain that is high quality and performs consistently. Grain quality is dependant on many factors and can vary significantly not only within a given field, but also within an individual head of wheat. This research was conducted to determine if grain of varying quality could be effectively segregated by kernel density. The study was conducted in northeastern Oregon in 2004 and 2005 years on soft white winter wheat collected from fields representing three different cropping systems. Grain collected was segregated by density using a gravity table and kernel density for each sample was determined. Baking and milling quality in terms of protein content, flour ash content, flour yield, water absorption and cookie quality were found to be highly correlated with kernel density with correlations ranging from 0.78 to 0.95. Overall quality score based on these quality factors was also highly correlated with kernel density with a correlation of 0.96. Fractions of wheat with higher density had significantly higher quality as compared to both un-segregated wheat and the fraction with the lowest density. These results indicated that wheat quality can be effectively segregated by kernel density. Use of a gravity table or other devices that separate kernels based on density could be used to improve the consistency and quality of grain delivered at the farm gate, thereby adding value and potentially increasing farm revenues.

Technical Abstract: Buyers of wheat desire grain that is high quality and performs consistently. Grain quality is dependant on many factors and can vary significantly not only within a given field, but also within an individual head of wheat. This research was conducted to determine if grain of varying quality could be effectively segregated by kernel density. The study was conducted in northeastern Oregon in 2004 and 2005 years on soft white winter wheat collected from fields representing three different cropping systems. Fifteen samples were collected from various landscape positions in each field. In 2004, a portion from each sample was combined to form a control sample representative of the entire field. The control sample was separated into four density fractions using a gravity table. In 2005, each sample was separated into seven fractions and analyzed for kernel density. Fractions were grouped by density and 14 samples from the range of densities were chosen for quality analysis. Grain quality in terms of test weight, protein, milling score, break flour yield, mixograph absorption and cookie diameter were found to be highly correlated with kernel density with R2 ranging from 0.78 to 0.95. Overall quality score based on these quality factors was also highly correlated with kernel density with an R2 of 0.96. Fractions of wheat with higher density had significantly higher quality as compared to both un-segregated wheat and the fraction with the lowest density. These results indicated that wheat quality can be effectively segregated by kernel density. Use of a gravity table or other devices that separate kernels based on density could be used to improve the consistency and quality of grain delivered, thereby adding value.