Degradation of Tocopherol Molecules and Its Impact on the Polymerization of Triacylglycerols during Heat Treatment of Oil.

Dominik Kmiecik,Bartosz Kulczyński,Aleksander Siger,Monika Fedko

doi:10.3390/molecules24244555

Dominik Kmiecik, Bartosz Kulczyński + Show 2 more

Open Access

https://doi.org/10.3390/molecules24244555

Copy DOI

Abstract

The aim of the study was to analyze the influence of the surface area to volume ratio of pressed and refined rapeseed oils on the changes in tocopherol content and polymerization of triacylglycerols during heating. In the study the pressed and refined rapeseed oil was heated at 170 °C, during 6, 12, and 18 h with three different surface area to volume (s/v) ratios (0.378, 0.189, and 0.126 cm−1). During heating, a decrease in tocopherols and increases in dimers, trimers, and oligomers of triacylglycerols were observed. However, the changes were dependent on the surface area to volume ratio used, type of oil and time of heating. The biggest changes were observed in oil with the biggest s/v ratio (0.378 cm−1), and the lowest when the s/v ratio was 0.126 cm−1. The pressed oil was characterized by faster degradation of tocopherols and slower increase of triacylglycerol polymer levels compared to refined oil.

Highlights

Fried food is one of the most popular types of food consumed worldwide
A lower level of total polar compounds (TPCs) content was found in refined oil (0.9%)
The study showed that the surface area to volume ratio of the heated oil had the biggest impact on the thermal changes of the oils and its components during frying

Summary

Introduction

Fried food is one of the most popular types of food consumed worldwide. By the frying process, we can obtain the elements of the main dishes and different types of side dishes such as French fries or other fried potato products. The popularity and magnitude of fried food consumption have two reasons: (I) sensory (texture, color, and flavor) and (II) economic (the frying process is easy to use, fast, and relatively cheap). As a result of the processes which occur during frying (dehydration of food, Maillard reactions), fried food is characterized by unique sensory properties such as golden color, characteristic flavors and crispy texture [1,2]. There are three main factors influencing oil quality: oxygen from the air, moisture from foodstuff and the temperature of the process. Because of these factors, the oil undergoes undesirable transformations as a result of oxidation, hydrolysis and thermal reactions [3]. As a result of oxidation in the heated oil, both lower and higher

Objectives

Methods

Results

Conclusion