Characterization of almond kernel oils of five almonds varieties cultivated in Eastern Morocco

摘要

This study focuses on characterization of almond kernel oils extracted mechanically from five sweet almond varieties Marcona, Fournat, Ferragnes, Ferraduel and Beldi), cultivated in eastern Morocco. Oil content, physicochemical parameters, triacylglycerol and fatty acid compositions were determined. Analyzed oils showed low acidity values that range between 0.77 – 0.88 %, peroxide values range between 6.43 – 16.39 meq/kg and Iodine values range between 98.42 – 103.90%. The principal fatty acid of almond kernel oils is oleic acid (C18:1); oils of Ferragnes-Ferraduel and Beldi varieties show higher values of C18:1 respectively of 72.87 and 71.62 %, however Fournat almond kernel oil shows the lowest content of C18:1 (63.54%). HPLC analysis of triglycerides was carried out, and results show that analyzed almond kernel oils are characterized by the dominance of trioleylglycerol (OOO) that contents range between a minimum of 31.48 % for Fournat’s oil and 43.82% for Ferragnes-Ferraduel’s oil. The oxidative stability of almond kernel oils was determined by rancimat tests as the induction period (IP, h recorded by a 743 Rancimat apparatus Metrohm, Switzerland). Results show that stability, of almond kernel oils is clearly influenced by the almond variety; Oxidative stability of tested almond kernel oils ranged between an IP = 20.28 h for Marcona oil and an IP =27.55 h for Ferragnes-Ferraduel.