Differential scanning calorimetry of palm kernel oil products

Abstract

Abstract A variety of fractionated and hydrogenated fats were derived from a commercial sample of Malayan palm kernel oil. These were studied by differential scanning calorimetry at different rates of cooling and heating. The resulting thermograms, and latent heats derived from them, were compared with one another and with underlying triglyceride compositions. This enabled three potential interpretations of the thermograms to be compared. The shapes of the cooling thermograms were most complicated, and dependent on the influence of the spontaneous crystallization, which followed supercooling when cooling rates of 8 C per min or more were imposed. Triglyceride composition had a less significant influence on the shapes of the curves, while polymorphism had almost no influence. The cooling thermograms, thus, are more complicated than heating thermograms, a conclusion at variance with one expressed elsewhere. The dynamic nature of the differential scanning calorimetry method is highlighted by the results of this work, and it is concluded that there are dangers in conducting differential scanning calorimetry studies at a single rate of temperature change.