Liaoning Provincial Bureau of Quality and Technical Supervision

Abstract This paper demonstrated a new approach for detecting pentosan content in wheat products enabled by phase‐transfer reaction technique. This approach was based on the phase‐transfer reaction of pentosans in wheat sample to furfural in an acidic medium. The hydrolysis reaction could be finished within 30 min at 90 °C, with a sulfuric acid concentration of 12.0 mol/L. The furfural generated from the hydrolysis of pentosan was then measured by headspace gas chromatography (HS‐GC) using a flame ionization detector (FID). The results showed that this method was precise (relative standard deviations (RSD)≤2.82 %) and accurate (relative differences (RD)≤6.49 % compared with the reference spectrophotometric method, the recoveries ranged from 98.1 to 102 %). Moreover, the developed approach is semi‐automated and efficient, which can be a good alternative method for the high‐throughput analysis of pentosan content in both laboratory and mill testing.

We investigate a simple and accurate method for quantitatively analyzing dissolved inorganic carbon in environmental water by reaction headspace gas chromatography. The neutralization reaction between the inorganic carbon species (i.e. bicarbonate ions and carbonate ions) in environmental water and hydrochloric acid is carried out in a sealed headspace vial, and the carbon dioxide formed from the neutralization reaction, the self-decomposition of carbonic acid, and dissolved carbon dioxide in environmental water is then analyzed by headspace gas chromatography. The data show that the headspace gas chromatography method has good precision (relative standard deviation ≤ 1.63%) and accuracy (relative differences ≤ 5.81% compared with the coulometric titration technique). The headspace gas chromatography method is simple, reliable, and can be well applied in the dissolved inorganic carbon detection in environmental water.