Testing the Antioxidant Effect of Essential Oils and BHT on Corn Oil at Frying Temperatures: a Response Surface Methodology

Abstract

Food habits worldwide have increased the demand for oxidative‐resistant oils that can be used for deep‐frying. Oxidative stability in oils can be improved by changing the fatty acid composition of the oil or by adding natural antioxidants to the oil. In this study, the effect of essential oils of seven plants; cinnamon, rosemary, sage, turmeric, clove, thyme and oregano enriched with carvacrol on the oxidative stability of corn oil at frying temperatures were studied. Experiments were conducted by using a PetroOxy device, a rapid small scale oxidation stability test. A central composite design was used to evaluate the effects of concentration of essential oil (X1: 1,500–5,000 ppm) and temperature (X2: 150–180 °C), on the induction time of corn oil. In order to compare the results with the synthetic antioxidant, butylated hydroxy toluene (BHT), another design was made with a concentration range (60–350 ppm) containing the legal upper limit of BHT, 200 ppm. Induction periods obtained from the accelerated oxidation test revealed that increasing temperature decreased the induction time of all the samples. However, the essential oils except for oregano oil had no significant antioxidative effect on corn oil, probably due to a lower content of their active components. The antioxidative effect of oregano oil was also found to be higher compared to BHT. At very high temperatures (e.g., 180 °C), the concentration of antioxidants had no effect on the induction periods.

Türki̇ye Pazarlarinda Satilan Yemekli̇k Sivi Ve Kati Yağlarin Bazi Bozulma Parametreleri̇

“…These values are within the limit (0.3% oleic acid) stated in the Turkish Food Codex Communiqué on Oils Called by Plant Name (TGK, 2012). In previous studies, FFA in CO was reported as 0.15% (Ali et al, 2016), and 0.12% (Inanc and Maskan, 2013). Our findings are similar to these results reported in the literature.…”

“…8.72 (P <0.05). In corn oil, p-AV was determined as 2.85 by Inanc Horuz and Maskan (2015), 1.44 by Günç Ergönül and Nergiz (2014), and 1.36 byInanc and Maskan (2013). Totox values in the samples were determined in the range of 11.91-17.59.…”

Thermo-Oxidation of Phytosterol Molecules in Rapeseed Oil during Heating: The Impact of Unsaturation Level of the Oil

“…Oxidation can be classified as one of the most important reaction influences on the oil quality and its nutritional value. The lipid oxidation caused by atmospheric oxygen and heat leads to the formation of rancid odors and flavors in frying food and decrease in the shelf life of oil; it also decreases the nutritional value and safety via the formation of potentially toxic secondary compounds [ 8 ]. The oxidation process is not only typical for unsaturated fatty acid but also for other oil compounds, such as tocopherols and phytosterols [ 9 , 10 , 11 , 12 ].…”

Effect of the phytochemicals curcumin, cinnamaldehyde, thymol and carvacrol on the oxidative stability of corn and palm oils at frying temperatures

“…However, the essential oils have been observed to have an effect on the oxidative stability of edible oils, especially during storage (Tomaino et al 2005;Maestri et al 2006;Al-Jaber et al 2011;Chen et al 2014). In our previous study, various essential oils showed poor antioxidant activity during the accelerated oxidation test of corn oil, presumably due to low concentration of active components and interference of extraneous pro-oxidative materials in the essential oils (Inanc and Maskan 2013).…”