On the fractional melting of milk fat and the properties of the fractions

Standard methods of fractionating milk fat from the melt produce solid fractions that exhibit melting at temperatures considerably lower than that used for the fractionation. The use of high concentrations of aqueous detergent, in the presence of ammonia as an aid to centrifugation, has resulted in this solid material being sub‐fractionated into a semi‐solid, plastic material and a crystalline solid. The technique may be applied directly to milk fat to produce three fractions at a given fractionation temperature. Fatty acid compositions and separations according to triglyceride number are recorded for the parent fats and their fractions. Melting fingerprints, obtained by differential scanning calorimetry, are shown for the various samples, and the heats of melting are discussed.