Microwave heating of different vegetable oils: Relation between chemical and thermal parameters

详细信息    查看全文

• 作者：Emma Chiavaro ; Maria Teresa Rodriguez-Estrada ; Elena Vittadini ; Nicoletta Pellegrini
• 关键词：Microwave heating ; Vegetable oils ; Differential scanning calorimetry ; Chemical stability indices
• 刊名：Lebensmittel-Wissenschaft und -Technologie
• 出版年：2010
• 出版时间：September 2010
• 年：2010
• 卷：43
• 期：7
• 页码：1104-1112
• 全文大小：439 K

文摘

Changes of DSC profiles and thermal properties (upon cooling and heating) were evaluated at different times of microwave heating on refined peanut (Pto), high oleic sunflower (HOSo) and canola (Co) oils and compared to the results obtained for standard chemical indices (free fatty acids, peroxide, p-anisidine, OSI time) and antioxidant capacity (Trolox equivalent antioxidant capacity). Co was more extensively oxidised by microwave heating than the other two oils probably as a consequence of the higher degree of unsaturation, even though it showed a higher antioxidant capacity. Microwave heating also induced alterations in both cooling and heating profiles of the oils, mainly in Pto and Co, shifting phase transitions towards lower temperature and enlarging temperature range. High statistical correlation coefficients were obtained among thermal properties both upon cooling and heating and chemical indices (i.e. free fatty acids and p-anisidine values). The analysis of both cooling and heating profiles and related thermal properties appears to be a valuable tool to assess different degrees of lipid thermoxidation induced by microwave in vegetable oils being also very useful for the ready-to-eat food sector and the vegetable oil industry.