SummaryA dilatometric method is presented which is of considerable convenience and reliability in application to commercial fats, notably shortening and margarine. The instrument is of volumetric type with mercury as confining fluid. The simplified calculations give results in terms of “Solid Content Index,” which is an approximation to the true % solid. The apparatus is applicable not only to basic study of composition and processing but is adaptable to hydrogenation control where it has been used with notable success for several years. With shortenings, for instance, the method cuts substantially the deviation from normal consistency encountered with the best thermal methods. Despite the high precision the determination can be completed in about two hours. Part of the reason for the combined precision and speed is a “tempering” step introduced to expedite approach to a steady state prior to final measurement.