Effect of soxhlet and cold press extractions on the physico-chemical characteristics of roasted and non-roasted chia seed oils

Abstract

While peroxide values of roasted and non-roasted chia seed oils obtained by cold press changed between 3.65 (non-roasted) and 14.12 meqO2/kg (roasted), peroxide values of chia seed oils extracted by Soxhlet extraction system were determined between 2.17 (non-roasted) and 8.53 meqO2/kg (roasted). Total wax contents of chia seed oils ranged between 56.74 mg/kg (roasted seed oil obtained by cold press system) to 138.87 mg/kg (non-roasted seed oil extracted by Soxhlet extraction). The linolenic acid contents of roasted and non-roasted chia oils obtained by cold press and Soxhlet extraction systems varied between 66.24 and 67.84% to 64.98 and 66.75%, respectively. β + γ-Tocopherols contents of roasted and non-roasted chia seed oils from cold press and Soxhlet extraction systems were determined between 901.6 and 917.3 mg/kg and 795.6 to 857.1 mg/kg, respectively. The rosmarinic acid contents of non-roasted and roasted chia seed oils obtained by cold press system decreased from 2.17 to 1.28 mg/g (p < 0.05), while oil extracted from Soxhlet method showed slight increase from 2.67 to 2.92 mg/g in non-roasted and roasted seeds respectively. This study revealed that roasting and extraction methods had significant effects on the micro constituents of oil from chia seeds. Due to these properties cold presses and non-roasted can be recommended.