The Measurement of Acetic Acid and Furfural Content in Steam-treated Woods and The Ruminal Change of Furfural into Furfuryl Alcoholin vitro

Abstract

A study on acetic acid and furfural, which are products of steamtreated woods, was carried out. Four kinds of steam-treated wood samples in the study had an average of 2.04 and 0.62% acetic acid and furfural, respectively, under the two conditions of 10.5 kg/cm² pressure for 20 min and 17 kg/cm² for 15 min. Since both compounds are volatile, measurement of the samples' moisture content by oven-drying at 105°C for 16 hrs resulted in about an 85% and 88% volatile loss of acetic acid and furfural, respectively, which led to an overestimation of moisture content. Apparent moisture content as calculated by drying had an overestimation of about 6% in volatile loss. On the other hand, moisture content as measured by the toluene distillation method was close to the estimated true moisture content and this method was considered to be much more applicable than drying. Furfural depressed the production of volatile fatty acids in vitro rumen fermentation, where it was observed that furfural changed into furfuryl alcohol and seemed to be little utilized by ruminants as an energy source. This indicates that furfural production in steam-treated woods is unfavourable.