Comparative study of polymers and total polar compounds as indicators of refined oil degradation during frying
The aim of this work was to compare the frying stability of refined olive pomace oil alone and blended with refined coconut oil during 60 successive sessions. Frying experiments were carried out at 180 °C and samples were evaluated by high-performance size-exclusion chromatography (HPSEC), measuring the polymers and polar compounds formed. The tocopherol content was also analyzed. At the end of the frying process, the lowest content of polymeric compounds (PC) and total polar compounds (TPC) were detected for the blend of refined olive pomace oil–refined coconut oil (ROPO/RCO) with 13.20% and 25%, respectively, compared to refined olive pomace oil (ROPO) pure with 16.9% and 34.5%, respectively. Hence, the present study based on PC and TPC as best quality indicators of frying oil degradation indicated that the frying behavior of ROPO pure significantly improved by the blending application with RCO and showed a higher chemical stability.
KeywordsDeep-fat frying Total polar compounds Polymeric compounds Solid-phase extraction
Refined olive–pomace oil
Refined coconut oil
High-performance size-exclusion chromatography
Saturated fatty acids
Polyunsaturated fatty acids
Total polar compounds
Oxidized triglyceride monomers
The authors would like to thank the “Ministère de l’Enseignement Supérieur et de la Recherche Scientifique” (Laboratory LR14ES08), Tunisia, for its financial support for this research work. The authors acknowledge also National Funds through Ministry of Higher Education-Tunisia for financing MedOOmics Project—“Mediterranean Extra Virgin Olive Oil Omics: profiling and fingerprinting”— “Arimnet2/0001/2015”.
Compliance with ethical standards
Conflict of interest
The authors declare no competing financial interest.
Compliance with ethics requirements
This article does not contain any studies with human or animal subjects.
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