Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties
Oil extracted from tiger nut is a good, edible source owing to its richness in unsaturated fatty acids. This study investigated the effects of the refining processes on the flavor components of crude tiger nut oil by GC-MS and focused on the thermal stability of the refined oil under high-temperatur...
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2025-01-01
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| author | Yue Zhao Yang Sun Heyi Sun Tianying Sun Jian Ren Chunli Song |
| author_facet | Yue Zhao Yang Sun Heyi Sun Tianying Sun Jian Ren Chunli Song |
| author_sort | Yue Zhao |
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| description | Oil extracted from tiger nut is a good, edible source owing to its richness in unsaturated fatty acids. This study investigated the effects of the refining processes on the flavor components of crude tiger nut oil by GC-MS and focused on the thermal stability of the refined oil under high-temperature conditions. Three different refining processes were evaluated: citric acid-assisted hydration degumming, alkali deacidification and bleaching. In the present study, the neutralization refining resulted in 11.67% losses. The refined oil had higher brightness and transparency. Moreover, 109 volatiles were identified, mainly including aldehydes, alcohols, pyrazines and furans, the characteristic flavor compounds of which present a fatty, fresh and nutty flavor. Hence, the refining processes have a significant effect on the flavor components of tiger nut oil, and the accumulated information can be helpful in increasing the tiger nut oil quality to meet the market value. The results of the thermal properties indicated the significant degradation of oleic acid and linoleic acid with prolonged heating, leading to increases in the acid value by 17 times and the peroxide value by 31 times after prolonged heating at 210 °C for 10 h compared with those without heating. When the refined tiger nut oil was heated at 210 °C for 4 h, the carbonyl value (62.6 meq/kg) exceeded the recommended value, and after heating for 8 h, the total polar compound percentages (50%, the instrument limit value) also exceeded the national standard. In order to extend the cooking heating time, it is necessary to appropriately decrease the heating temperature. This study provides a scientific reference for the frying of tiger nut oil in food and the high-temperature treatment of food containing tiger nut oil. |
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| institution | Kabale University |
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| spelling | doaj-art-5fac55cbad144c668f034a8354c3ce772025-01-24T13:33:12ZengMDPI AGFoods2304-81582025-01-0114230110.3390/foods14020301Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal PropertiesYue Zhao0Yang Sun1Heyi Sun2Tianying Sun3Jian Ren4Chunli Song5College of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaCollege of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaCollege of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaCollege of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaCollege of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaCollege of Food and Biological Engineering, Qiqihar University, Qiqihar 161006, ChinaOil extracted from tiger nut is a good, edible source owing to its richness in unsaturated fatty acids. This study investigated the effects of the refining processes on the flavor components of crude tiger nut oil by GC-MS and focused on the thermal stability of the refined oil under high-temperature conditions. Three different refining processes were evaluated: citric acid-assisted hydration degumming, alkali deacidification and bleaching. In the present study, the neutralization refining resulted in 11.67% losses. The refined oil had higher brightness and transparency. Moreover, 109 volatiles were identified, mainly including aldehydes, alcohols, pyrazines and furans, the characteristic flavor compounds of which present a fatty, fresh and nutty flavor. Hence, the refining processes have a significant effect on the flavor components of tiger nut oil, and the accumulated information can be helpful in increasing the tiger nut oil quality to meet the market value. The results of the thermal properties indicated the significant degradation of oleic acid and linoleic acid with prolonged heating, leading to increases in the acid value by 17 times and the peroxide value by 31 times after prolonged heating at 210 °C for 10 h compared with those without heating. When the refined tiger nut oil was heated at 210 °C for 4 h, the carbonyl value (62.6 meq/kg) exceeded the recommended value, and after heating for 8 h, the total polar compound percentages (50%, the instrument limit value) also exceeded the national standard. In order to extend the cooking heating time, it is necessary to appropriately decrease the heating temperature. This study provides a scientific reference for the frying of tiger nut oil in food and the high-temperature treatment of food containing tiger nut oil.https://www.mdpi.com/2304-8158/14/2/301cold-pressed tiger nut oilrefining processvolatile compoundsthermal properties |
| spellingShingle | Yue Zhao Yang Sun Heyi Sun Tianying Sun Jian Ren Chunli Song Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties Foods cold-pressed tiger nut oil refining process volatile compounds thermal properties |
| title | Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties |
| title_full | Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties |
| title_fullStr | Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties |
| title_full_unstemmed | Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties |
| title_short | Changes in the Flavor of Cold-Pressed Tiger Nut Oil (<i>Cyperus esculentus</i> L.) During Refining Processes and Evaluation of Its Thermal Properties |
| title_sort | changes in the flavor of cold pressed tiger nut oil i cyperus esculentus i l during refining processes and evaluation of its thermal properties |
| topic | cold-pressed tiger nut oil refining process volatile compounds thermal properties |
| url | https://www.mdpi.com/2304-8158/14/2/301 |
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