Influence of Growing Location on the Phytochemical Content of Pecan (Carya illinoinensis) Oil

Pecan (Carya illinoinensis) is a tree nut native to North America with high oil content. Pecan oil is rich in unsaturated fatty acids and other lipid soluble phytochemicals. Many geographical and environmental factors are responsible for the phytochemical content of the oil, and little current information exists on the properties of pecans grown in northern México. We formulated the hypothesis that pecans grown in multiple locations are exposed to different environmental conditions which alter the concentration of the phytochemicals in the oil. We characterized oil from pecans harvested in 2009 and 2010, in three different regions in northern Mexico. The content of individual fatty acids varied significantly within growing location (mainly oleic and linoleic, which were inversely related) and from year to year (mainly linolenic). Phytosterols and tocopherols also showed significant variation among locations; polyphenols were statistically similar in all samples. Oxidative stability of pecan oil, evaluated by differential scanning calorimetry, was similar to other oils with a similar content of unsaturated fatty acids. It may be concluded that the chemical composition of pecan oil is sensitive to the environment in which it is produced, but on average, the studied pecan oils were good sources of phytochemicals.