Journal of Supercritical Fluids, Vol.116, 215-222, 2016
Increasing the value of pecan nut [Carya illinoinensis (Wangenh) C. Koch] cake by means of oil extraction and antioxidant activity evaluation
Pecan nut is a dried fruit, appreciated worldwide because of its particularly pleasant flavor and its wealth of healthy bioactive components. The nut oil is rich in monounsaturated fatty acids and vitamin E, currently recognized as antioxidant agents. The oil extraction from the pecan nut cake, an industrial byproduct from oil production, is an alternative to value the industrial application of the pecan nut. In the present work, different extraction processes, low-pressure methods (LPE) and supercritical fluid extraction (SFE) were investigated to obtain the pecan nut cake extract (residual oil). The aspect evaluated was the processes extraction yields, the fatty acid profile and antioxidant activity, by DPPH, ABTS and beta-carotene methods, of the resulting extracts. Results show that higher extraction yields were obtained by Soxhlet with ethanol (69.6 +/- 0.3%), by Soxhlet with acetone (641 +/- 3%), and by SFE at 300 bar and 313.15 K (58.4 +/- 0.2%). The SFE of pecan nut cake reached 98% extraction of the lipid fraction from the raw material. Oleic acid was the main fatty acid present in the cake oil obtained by SFE and by LPE. The antioxidant potential of the pecan cake oil presented high values, similar to gallic acid. The present study has shown that SFE can be used as an alternative method for the extraction of oil from a byproduct rich in acid oleic and other nutrients. The results from this work suggest the importance of these agro industrial residues as a potential for generating alternative high value by-products. (C) 2016 Elsevier B.V. All rights reserved.