Rampazzo Valéria, Ribeiro Leomara Floriano, Santos Poliana Macedo, Ferreira Maresa Custódio Molinari, Bona Evandro, Maciel Giselle Maria, Haminiuk Charles Windson Isidoro
Universidade Federal do Paraná, Programa de Pós-Graduação em Engenharia de Alimentos (PPGEAL), Curitiba, CEP (81531-980), PR, Brazil.
Universidade Tecnológica Federal do Paraná, Programa de Pós-Graduação em Química (PPGQ), Câmpus Curitiba, CEP (81280-340), PR, Brazil.
J Chromatogr B Analyt Technol Biomed Life Sci. 2018 Apr 1;1081-1082:118-125. doi: 10.1016/j.jchromb.2018.02.031. Epub 2018 Feb 26.
The effect of heating in twenty-four different oil samples was evaluated via iodine value (IV), gas chromatography (GC) and mid-infrared (MIR) analyses. Common components and specific weights analysis (CCSWA) was applied to distribute the samples according to their most relevant characteristics, thereby revealing the influence of heating on composition. Instrumental analysis indicated a high amount of beneficial fatty acids, such as alpha-linolenic acid, in less exploited oils such as chia oil. This oil can present nutritional damage when subjected to high temperatures and is thus less recommended for frying. Conversely, oils containing high amounts of linoleic acid, such as almond and nut oils, as well as those containing equivalent amounts of alpha-linolenic and linoleic acids, such as golden flaxseed and flaxseed oils, displayed greater resistance to temperature. The 3008/cm band exhibited greater intensity in oils with a higher degree of unsaturation, such as chia and linseed oils, a phenomenon mainly influenced by the presence of linoleic and alpha-linolenic fatty acids. After heating, there was a decrease in the intensity of this band. The main parameter discriminating the tested oil samples based on CCSWA was the degree of unsaturation. Overall, the employed statistical method was effective in analyzing the data obtained via the applied techniques, revealing the influence of each assessed parameter.
通过碘值（IV）、气相色谱（GC）和中红外（MIR）分析评估了24种不同油样加热后的效果。采用共同成分和比重分析（CCSWA）根据样品最相关的特征对其进行分类，从而揭示加热对成分的影响。仪器分析表明，在奇亚籽油等较少使用的油中含有大量有益脂肪酸，如α-亚麻酸。这种油在高温下会出现营养损害，因此不太推荐用于油炸。相反，含有大量亚油酸的油，如杏仁油和坚果油，以及含有等量α-亚麻酸和亚油酸的油，如黄金亚麻籽和亚麻籽油，对温度表现出更大的耐受性。在不饱和度较高的油中，如奇亚籽油和亚麻籽油，3008/cm波段表现出更强的强度，这一现象主要受亚油酸和α-亚麻酸的存在影响。加热后，该波段的强度降低。基于CCSWA区分测试油样的主要参数是不饱和度。总体而言，所采用的统计方法有效地分析了通过应用技术获得的数据，揭示了每个评估参数的影响。
