Absorbance spectra of edible oils were obtained using a Fourier transform middle-Infrared spectrophotometer (FTIR Tensor 27 from Bruker Optics) equipped with liquid nitrogen cooled Mercury- Cadmium-Telluride (MCT) detector and GRASEBY SPECAC three-bounce Attenuated Total Reflectance (ATR) crystal of Zinc Selenide. The ATR crystal was completely covered with the sample and kept at 65 ± 1 C, to ensure that the sample was fully melted, using an automatic temperature controller of GRASEBY SPECAC.
The ATR accessory allows precise controlling of the sample temperature owing to the small amount of sample needed to cover the surface area of the ATR crystal. This technique is convenient
for the analysis of small amounts of fat extracted of low fat foods
because it requires 50 lL–100 lL of sample.