Physico-Chemical Characteristics of Flaxseed Oil and Its Oxidation in Frozen Condition

Some physico-chemical characteristics of Iranian linseed oil (Linum usitatissimum) such as oil content (44. 25%)، refractive index (1. 47)، peroxide (7. 21meqO2/Kg Oil)، iodine (170. 67gI2/100g Oil)، acid (3. 10mgNaOH/g Oil) and saponification (191. 73mgKOH/g Oil) values and fatty acid profile (C:، C18:0، C18:1، C18:2، C18:3) were studied. For preservation of ω-3 ingredients، the linseed oil that containing 43. 18% of ω-3 fatty acid، were kept in frozen condition (nitrogen atmosphere and -30 º C temperatures) and its peroxide value was determined after 0، 7، 30، 60 and 90 days. Statistical analysis showed significant difference (p<5%) average amount of peroxide value only in first 7 days of storage time and its increase (8. 30%) conformed to international standard.