TITLE:
Monitoring Oxidative Degradation of Thermally Stressed Palm Olein Shortening by Spectroscopic and Chromatographic Techniques
AUTHORS:
Adnan Mujahid, Saba Nazir, Muhammad Hamid Raza, Azeem Intisar, Tajamal Hussain, Ahsan Sharif, Ejaz Ahmed
KEYWORDS:
Palm Olein, Shortening, Oxidation, ATR-FTIR, GC-MS
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.8 No.12,
December
24,
2018
ABSTRACT: Deep
frying with repeated use of same edible oil leads to the formation of lipid
oxidation products. The presence of these oxidized products formed during
frying at elevated temperature is hazardous for human health and therefore,
requires prompt analysis for ensuring its fitness/quality. In this study,
oxidative degradation of thermally stressed edible oils canola, sunflower and
palm olein shortening was studied at 180°C ± 5°C up to 48 hours. Palm olein
shortening remained stable during this period as the increase in its acid value
was significantly less than canola and sunflower seed oils. The shortening
samples were further studied by attenuated total reflectance Fourier
transformation infrared (ATR-FTIR) and gas chromatography mass spectrometry
(GC-MS) to evaluate the formation of various oxidation products due to thermal
stress. ATR-FTIR indicates the formation of free fatty acids (FFAs), aldehyde
groups and change in degree of unsaturation while GC-MS gives important information
about profile of FFAs. The combination of these analytical techniques is useful
for rapid and highly sensitive analysis of oxidized edible oil thus, ensuring
its quality and fitness for safe use.