Specifies a volumetric method, after distillation, for determining of neutral oils, and a titrimetric method, after distillation, for determining of pyridine bases. The principle is based on distillation from an aqueous alkaline solution of a test portion. Measurement of the volume of neutral oils collected. Titration of the bases present in the aqueous distillate and in the oils with standard volumetric hydrochloric acid solution using methyl orange and xylene cyanol FF as indicator. An assembled distillation apparatus is shown in a figure.