Cereal Chem 57:212 - 216.  |  VIEW ARTICLE
Gasograph: Design, Construction, and Reproducibility of a Sensitive 12-Channel Gas Recording Instrument.

G. L. Rubenthaler, P. L. Finney, D. E. Demaray, and K. F. Finney. Copyright 1980 by the American Association of Cereal Chemists, Inc. 

The gasograph is an instrument designed to measure and continuously record the gas produced in 12 fermenting doughs (of about 10 g of flour). Values are recorded as gasograph units (GU), which can be readily expressed as millimeters of mercury or cubic centimeters of gas. Gasograph channel to channel reproducibility is at least equal to that of different manometric-type and gauge-type nonrecording instruments. The first two gasographs produced essentially identical results on successive days at two research laboratories, comparing fermentation rates of two yeast levels (3.5 and 7.25%) and three straight grade baker's flours formulated in sponges containing 6% sucrose, 1.5% NaCl, and 150% water in addition to flour and yeast. The average of the coefficients of variability of treatments within laboratories was 0.55%, and within channels between laboratories was 0.75%. Thus, the excellent reproducibility between laboratories was somewhat lower than that within laboratories. Typical gasograms demonstrate the high reproducibility of the actions of formula ingredients, yeast, sugar, and diastatic malt. The coefficient of variability was 0.69%. The gasograph can be used to indicate the presence or absence of inhibitors or stimulators of yeast respiration and to investigate the interaction of formula ingredients and fermentation rates during various stages of the fermentation and proofing of dough. Traces of alpha-amylase in wheat and flour can be easily detected with the instrument.