Five Methods for Determination of Silage Dry Matter

Dry matter contents of 18 high-molsture feed samples were determined by: 1) Oven drying at 100 C, 2) oven drying at 70 C, 3) freeze drying, 4) toluene distillation (uncorrected), and 5) toluene distillation (corrected).Means for the five methods were: 1) 44.44, 2) 46.80, 3) 47.21, 4) 47.70, and 5)48.24%.Up to 14.64% loss of dry matter by drying depended upon the method and the sample.Oven drying at 100 C caused maximum loss of dry matter while toluene distillation (corrected) showed the highest dry matter in all samples and is assumed to be most accurate of the systems compared.Corrections for volumes of total acids, ethanol, and ammonia in the toluene distillate caused significant changes in the dry matter compared to uncorrected toluene distillation method.The apparatus for toluene distillation was modified from those described in the literature which along with other considerations reduced distillation time from between 6 and 8 to 1.5 hours.