A total of 15 walnut (Juglans regia L.) samples from 15 cultivars from different geographical areas (Villaviciosa, Colunga, Ribadesella, Llanes, Nava, Peñamellera and Sariego) from Asturias, Spain were studied. Samples of virgin walnut oil were obtained from dehusked ground walnuts by extraction at a pressure of 160 kg cm -2 and temperature below 40°C for 3 min. The oil obtained by pressure was filtered for analysis. Fatty acid, sterol and tocopherol compositions as determined by capillary column gas chromatography (GC) and triacylglycerols composition as determined by high performance liquid chromatography (HPLC) are reported. The overall composition (percentages of husk, oil and moisture) was also determined. The higher percentages of fatty acids, as determined by capillary GC, corresponded to palmitic (6.11 ± 0.06-7.49 ± 0.04%), oleic (11.70 ± 1.10-18.90 ± 1.19%), linoleic (59.81 ± 1.03-64.77 ± 1.25%) and linolenic (11.11 ± 0.05-15.65 ± 1.09%). c-Tocopherol was the major component of the total tocopherols in the sample under study (289.01 ± 6.02-676.52 ± 5.98 mg kg -1 oil). b-Sitosterol was the major sterol found (78.61 ± 1.45-86.50 ± 1.35%) followed by D 5 -avenasterol (5.54 ± 0.92-13.81 ± 1.06%). The main triacylglycerides were LLL (24.67 ± 1.31-29.

Nine varieties of virgin hazelnut oil from different autochthonous cultivars from distinct locations in Asturias (Spain) were obtained by extraction under a pressure of 280 kg/ cm 2 at a temperature of 45 7C. The extracted oils were separated and filtered. The overall composition (percentages of husk, oil and moisture) of unhusked seeds was determined as well as moisture, ash, total sulfur and heat power of the husks for their possible use as biomass. Recovery of the oil extraction procedure for its application to the production of extra virgin edible hazelnut oil was studied. Fatty acid, tocopherol and sterol compositions as determined by capillary column gas chromatography and triglyceride compositions as determined by high performance liquid chromatography are reported in this study. All values were compared with a Turkish and a French hazelnut oil, with solvent-extracted hazelnut oil and with a 75/25 blend. A cluster analysis was performed as a criterion to differentiate the different hazelnut oils as groups.

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Although it is well known that oil temperature is an essential factor for determining the deacidification mass rate and the final free fatty acids content, the influence of the temperature of the gas distillates above the liquid phase in the deodorizer on the oil temperature is much less understood. An extensive study of the effect of the temperature of the oil and of the gas distillates was undertaken in a continuous deodorizer, comparing the results with those obtained using a batch process. Variations in temperature from the temperature obtained without additional heating of the gases to a higher temperature than that of the oil were assayed for the gas distillates at the head of the deodorizer. It was possible to obtain low outlet free fatty acid contents at lower oil temperatures by controlling the overheating of the distillates, even for very high initial free fatty acids content, indicating that this is an essential variable to consider in distillation. However, increasing the temperature of the gas distillates above that of the oil sometimes produces a negative effect in deacidification.