Effect of Extraction Method and Sesame Oil (Sesamum indicum L)Type on Lecithin Yield and Study of Its Physicochemical Properties

Abstract

The aim of this study was to evaluate the effect of the type of sesame oil (roasted and unroasted) and different extraction methods on the yield of lecithin and its physicochemical properties, Three methods were used to extract lecithin, including aqueous extraction, acid extraction, and ultrasonic-assisted extraction at different times (10, 20, 30) minutes, The results showed significant differences in the lecithin yield depending on both the type of oil and the extraction method, as well as their interaction. The ultrasonic extraction method for 10 minutes achieved the highest lecithin yield of 3.912% ,whilst the aqueous method recorded the lowest yield of 0.510%, Unroasted oil also yielded a higher average yield compared to roasted oil. The results of the chemical analysis showed that the crude lecithin contained 28.14% moisture and 7.01% ash. The lecithin possesses good quality characteristics, with an acid value (AV) of 1.597 mg KOH/g and a peroxide value (PV) of 2.610 meq O₂/kg, while the free fatty acid (FFA) was 2.173%, Antioxidant activity testing showed that the extracted lecithin possessed good free radical scavenging capacity, with activity increasing with concentration; the highest inhibition rate for DPPH free radicals was 81% at a concentration of 0.8 mg/ml, FTIR analysis also confirmed the presence of functional groups characteristic of phospholipids, such as CH₂, C=O and ¯PO₂, and the results generally indicate that the ultrasonic extraction method is one of the most efficient methods for extracting sesame lecithin.