Thermal Degradation of Tocopherol and Oxidation Products in Different Olive Oil Classes Using Uv-Vis Spectroscopy and McR-Als

Abstract

Extra virgin olive oil, virgin olive oil and mixed oil were analyzed by UV-Vis spectroscopy and Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS). When the oils were heated at high temperatures (frying), oxidation products were formed which were harmful to human health and antioxidants present were degraded. The aim of this study was to evaluate tocopherol (an antioxidant present in oils) and the behaviour of oxidation products in different olive oil classes. MCR-ALS results showed that degradation started at 70 ºC for extra virgin olive oil, while tocopherol concentration decreased and oxidation products increased starting at 40 ºC in virgin olive oil. In mixed oil, commercialized as a mixture of 85% soybean oil and 15% olive oil, tocopherol concentration started to decrease and oxidation products increase at 30 ºC. The results suggested that extra virgin olive oil offered more resistance to increasing temperatures, while virgin olive oil and mixed oil were less resistant. ]]>

Maternal oxidized soybean oil exposure in rats during lactation damages offspring kidneys via Nrf2/HO‐1 and NF‐κB signaling pathway

“…The primary oxidation products are hydrogen peroxide (H 2 O 2 ) and conjugated dienes, which then undergo other chemical reactions to produce many secondary oxidation products, including aldehydes, ketones, alcohols, epoxy compounds, carboxylic acids, oligomers, and polymers 8 . The original antioxidants also become degraded and form oxidation products harmful to human health 9 . Oxidized lipid products are associated with various pathological conditions, such as cardiovascular diseases and different types of cancer 10 .…”

“…8 The original antioxidants also become degraded and form oxidation products harmful to human health. 9 Oxidized lipid products are associated with various pathological conditions, such as cardiovascular diseases and different types of cancer. 10 According to reports, the final product of lipid peroxide, represented by 4-hydroxynonenal (4-HNE), is highly carcinogenic.…”

UV-Vis spectroscopy and chemometrics applied to residues monitoring in sewage

“…MCR-ALS has been proposed and extensively used to resolve multiple pure responses and concentrations of the components present in unknown mixtures. It has been applied to the analysis of the environmental samples (Peré-Trepat et al, 2005;Peré-Trepat & Tauler, 2006) and UV-spectral data (De Luca et al, 2010;Março et al, 2011;Jayaramana et al, 2012;Gonçalves et al, 2014a;Gonçalves et al, 2014b;Gonçalves et al, 2015).…”

Projeto Da Horta Para a Alimentação Escolar: Relato De Uma Experiência Na Educação Básica, Salvador, Ba

“…A classificação do azeite de oliva é determinada a partir da porcentagem de ácido oleico, o azeite de oliva considerado "puro" que é constituído por azeite de oliva refinado e azeite de oliva virgem, pode ter no máximo 1,0 g/100 g em ácido oleico (ANVISA, 2005), enquanto o azeite virgem pode variar de e 0,81% a 2% e o azeite extra virgem no máximo 0,8% de ácido oleico (GONÇALVES, 2015).…”