Hybrid hazelnut oil characteristics and its potential oleochemical application

The demand for vegetable oils as alternatives to petroleum is growing. Vegetable oils offer performance advantages and are environmentally friendly. Soybean oil is one of the promising resources and has been studied extensively. However, soybean oil lacks thermal and oxidative stability and has undesirable cold flow properties. These disadvantages are directly related to its fatty acid composition. Therefore, new varieties with superior oil traits are needed. Hybrid hazelnut oil is just such an attractive raw material. The objective of this study was to investigate hybrid hazelnut oil fatty acid composition and several other important properties in view of potential oleochemical applications. Hazelnut oil, derived from hybrid hazelnuts (Corylus sp. L.) grown in southeastern Nebraska, was extracted using a Soxhlet extractor. The oil contents of 25 different hybrid hazelnut samples ranged from 51.4% to 75.1% of the dry weight of nut kernels. Fatty acid profiles were analyzed by gas chromatography. It was found that oleic and linoleic acids comprised more than 90% of fatty acids in the oil. Oxidative onset temperature (OOT) was used as an indicator of thermal stability. The OOT of the hazelnut oils were in the range of 184.7–190.4 °C, which were higher than that of soybean oil (148.4 °C). The cloud points of hazelnut oils (−12.4 to −14.9 °C) were lower than that of soybean oil (−9.9 °C). The iodine values were in the range of 90.6–97.4. The kinematic viscosity of hazelnut oil was 65.7 ± 2.2 mm2/s at 22 °C. These initial analyses suggest that hazelnut oil is a potential feedstock for oleochemicals.