Effect of Pulsed Electric Fields (PEF) on Extraction Yield and Stability of Oil Obtained from Dry Pecan Nuts (Carya illinoinensis (Wangenh. K. Koch))
L. M. Rábago-Panduro, Mariana Morales‐de la Peña, María‐Paz Romero, Olga Martı́n-Belloso, Jorge Welti‐Chanes
Foods
Abstract
Pulsed electric fields (PEF) have been reported to increase the total oil extraction yield (OEY<sub>TOTAL</sub>) of fresh pecan nuts maintaining oil characteristics and increasing phenolic compounds in the remaining by-product. However, there is no information regarding the PEF effect on dry pecan nuts. Dry kernels were pretreated at three specific energy inputs (0.8, 7.8 and 15.0 kJ/kg) and compared against untreated kernels and kernels soaked at 3, 20 and 35 min. OEY<sub>TOTAL</sub>, kernels microstructure, oil stability (acidity, antioxidant capacity (AC), oil stability index, phytosterols and lipoxygenase activity), along with by-products phenolic compounds (total phenolics (TP), condensed tannins (CT)) and AC were evaluated. Untreated kernels yielded 88.7 ± 3.0%, whereas OEY<sub>TOTAL</sub> of soaked and PEF-treated kernels were 76.5-83.0 and 79.8-85.0%, respectively. Kernels microstructural analysis evidenced that the 0.8 kJ/kg pretreatment induced oleosomes fusion, while no differences were observed in the stability of extracted oils. PEF applied at 0.8 kJ/kg also increased by-products CT by 27.0-43.5% and AC by 21.8-24.3% compared to soaked and untreated kernels. These results showed that PEF does not improve OEY<sub>TOTAL</sub> when it is applied to dry pecan nuts, demonstrating that kernels' moisture, oil content and microstructure play an important role in the effectiveness of PEF.
Extracted Claims
3 claims extracted from this paper into the knowledge graph
PEF at 0.8 kJ/kg increased by-products condensed tannins (CT) and antioxidant capacity (AC)
“PEF applied at 0.8 kJ/kg also increased by-products CT by 27.0-43.5% and AC by 21.8-24.3% compared to soaked and untreated kernels.”
PEF at 0.8 kJ/kg induced oleosomes fusion
“Kernels microstructural analysis evidenced that the 0.8 kJ/kg pretreatment induced oleosomes fusion, while no differences were observed in the stability of extracted oils.”
pulsed electric fields (PEF) did not improve total oil extraction yield (OEY<sub>TOTAL</sub>)
“These results showed that PEF does not improve OEY<sub>TOTAL</sub> when it is applied to dry pecan nuts, demonstrating that kernels' moisture, oil content and microstructure play an important role in ...”