Methods for thermal values of fat determination
Although it is customary to speak of the melting points of fats, they really have no melting point in the proper sense of the word. Pure substances have a sharp melting point, i.e., the temperature of transition from the solid to the liquid state. Fats are invariably mixtures of mixed triglycerides and each individual triglyceride has its own melting point. Fats, therefore, have a melting range.

A variety of methods exist for the determination of the melting point (mp) of fats. These include the Wileymp (AOCS Method Cc 2-38), open capillary slip point, softening point and METTLER TOLEDO's dropping point (AOCS Method Cc 18-80). The conditions under which the tests are performed influence the values obtained. The methods were compared using a variety of fats. The METTLER TOLEDO dropping point values were found to coincide with the extrapolated solid fat curves obtained using wide-line NMR for all fats except butterfat.

The perfect solution
The METTLER TOLEDO dropping point is an automated version of the Ubbelohde dropping-point method. A sample cup filled with fat is placed in an automatically heated furnace where the falling of the first drop of fat is sensed photometrically and indicated on a digital display. The standard deviations of the slip melting point determinations were dependent on the kind of fat measured between 0.3 °C and 1.2 °C. The same measurements, using a METTLER TOLEDO FP83HT dropping point cell, resulted in standard deviations between 0.1 °C and 0.3 °C. The reproducibility of the METTLER TOLEDO dropping point and softening point are excellent compared to the slip point.

Measuring the dropping point of fats with the METTLER TOLEDO FP83HT offers the easy, reliable and automated determination of the melting point of fats.