Comparative Assessment of Quality Deterioration in Various Vegetable Oils During Deep-Fat Frying of Crispy Meat

TL;DR

This study compares how different vegetable oils degrade during deep-frying of crispy meat, focusing on safety and quality changes.

Contribution

The study identifies palm oil and canola oil as more stable during frying, with lower deterioration and contaminant formation.

Findings

Palm oil and canola oil showed significantly lower total polar compounds and oxidation markers after frying.

Initial high levels of MCPDEs and GE in palm oil decreased during frying, unlike in other oils.

Color parameters like L* and b* correlated with oil deterioration markers, suggesting their use as quality indicators.

Abstract

Deep-fat frying is widely used, but high temperatures and complex food matrices promote oil deterioration and harmful substance formation, posing risks to food safety and oil quality. This study evaluated five vegetable oils—sunflower oil (SFO), canola oil (CNO), palm oil (PO), cottonseed oil (CSO), and soybean oil (SBO)—during deep-fat frying of crispy meat to elucidate oil deterioration and contaminant formation patterns. After 32 h of frying, total polar compounds (TPCs) of PO and CNO were 29.8% and 32.6%, significantly lower than the other oils. Similar trends were observed for total oxidation value (TOTOX), carbonyl value (CV), and polar polymers, suggesting higher oxidative stability of PO and CNO, as confirmed by principal component analysis (PCA). Initial monochloro-1,2-propanediol esters (MCPDEs) and glycidyl ester (GE) in PO were relatively high (e.g., 3-MCPDE: 3630 μg/kg) but decreased over time during frying, whereas levels in SFO, CSO, and SBO remained low. Pearson’s correlation analysis indicated diacylglycerols (DAG) and monoacylglycerols (MAG) were positively correlated with MCPDEs and GE (p < 0.05). L* and b* values were positively correlated with polar polymers and contaminants, indicating that color parameters may serve as rapid, non-invasive auxiliary indicators of oil quality but should be combined with other indices for accurate evaluation.

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