Premium
Correction of wheat meal falling number to a common barometric pressure at simulated laboratory elevations of 0–1,500 m
Author(s) -
Delwiche Stephen R.,
Rausch Steven R.,
Vinyard Bryan T.
Publication year - 2018
Publication title -
cereal chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.558
H-Index - 100
eISSN - 1943-3638
pISSN - 0009-0352
DOI - 10.1002/cche.10044
Subject(s) - atmospheric pressure , elevation (ballistics) , falling number , chemistry , falling (accident) , polynomial regression , linear regression , range (aeronautics) , atmospheric sciences , meteorology , mathematics , statistics , food science , geography , wheat flour , geology , geometry , medicine , environmental health , materials science , composite material
Background and objectives Falling number, a procedure that indirectly characterizes germination enzyme activity in wheat grain by measuring the viscous behavior of a heated flour–water or meal–water mixture, is affected by the immersion water bath temperature. Maintained at boiling point, the water bath temperature is determined by barometric pressure which changes with land elevation. The effect of elevation, hence barometric pressure, on falling number over a simulated elevation range of near sea level (760 mm Hg) to 1,524 m (632.4 mm Hg) was modeled. Findings First‐order polynomial linear regression equations were developed on log‐transformed mean falling number readings to correct non‐sea level readings to sea level conditions represented as pressure, elevation, or water bath boiling temperature. With correction, the range in standard deviation of falling number over five simulated elevations declined to 0.9–14.1 s, from a precorrection range of 13.2–50.9 s. Conclusions The pressure effect was greatly reduced with application of the model. The correction functions are continuous linear relationships in the log domain and applicable to the entire simulated elevation range. Significance and novelty Ready availability of handheld digital barometers or reliance on the built‐in feature of barometric pressure measurement in newer falling number instruments now allow for ready correction of falling number to prevailing environmental conditions, which will translate into a fairer assessment of wheat quality in commercial trade.