Spectra and carbonyl index changes on processed beef fats using fourier transform infrared spectrometer and principal component analysis

Abstract

Cooking processes such as frying, steaming, and roasting will modify or change the fatty acids composition in the fats. The objective of this research was to study and evaluate the changes in spectra profile included carbonyl index that occurs on cooked beef fats using Fourier Transform Infrared spectroscopy and principal component analysis, where the fat extraction using the Folch method. The results showed the spectra profiles of processed beef fats were modified at wavenumbers of 2028 cm⁻¹ which was C–H stretching vibrational, 1413 cm⁻¹ and 1218 cm⁻¹ of C–H (CH₂) scissoring bending, and 960 cm⁻¹ of CH=CH trans compared to raw beef fat. Steamed and fried beef fats have additional peaks at wavenumbers of 1239 cm⁻¹ and 757 cm⁻¹, respectively. These results also indicated that cooking processes have the potential to form trans fatty acids. In addition, the processes on beef fats also cause a decrease in the carbonyl index due to the formation of the volatile carbonyl. Finally, principal component analysis of infrared spectra showed that each processed beef fat can be clustered and classified as well as a fat extract from a beef meatball.

Keywords:

• Beef fat
• carbonyl index
• cooking process
• chemometric analysis
• vibrational profile

Acknowledgement

We acknowledge to Directore of LPPM Djuanda University, Mrs. Ginung Pratidina for supervising us in the research.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

We acknowledge to Hibah Penelitian Kerjasama Antar Perguruan Tinggi from Ministry of Research, Technology, and Higher Education of The Republic of Indonesia under Grant [0826/K4/KM/2018].