Stability of Cold-Pressed Oil from Commercial Indian Niger (Guizotia abyssinica (L.f.) Cass.) Seed as affected by Blending and Interesterification

• Published in: Journal of the American Oil Chemists' Society Vol. 92; no. 11-12; pp. 1671 - 1680
• Main Authors: Bhatnagar, A. S, Gopala Krishna, A. G
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2015; Springer Nature B.V
• Subjects: Agriculture; Biomaterials; Biotechnology; Blending; Chemistry; Chemistry and Materials Science; Coconut oil; fatty acid composition; Flowers & plants; Food Science; Guizotia abyssinica; Indian niger seeds (Guizotia abyssinica (L.f.) Cass.); Industrial Chemistry/Chemical Engineering; Interesterification; linoleic acid; mixing; Niger seed oil; Oil blends; Oils & fats; oleic acid; Olive oil; olive pomace; Original Paper; oxidation; Oxidative stability; peroxide value; Polyunsaturated fatty acids; Relative humidity; Rhizomucor; saturated fatty acids; Seeds; Niger seed oil; Coconut oil; Blending; Oxidative stability; Indian niger seeds; Interesterification; (L.f.) Cass.; Olive oil; Oil blends
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-015-2723-3

Blending and interesterification of cold-pressed oil from commercially available niger (Guizotia abyssinica (L.f.) Cass.) seeds was performed to improve its stability. The fatty acid composition of cold-pressed niger seed oil (NSO) revealed that it contained a huge amount of polyunsaturated linoleic acid (69.2 %). NSO being rich in polyunsaturated fatty acids (PUFA) was susceptible to oxidation and hence was blended with saturated fatty acid (SFA) rich coconut oil (CNO) and monounsaturated fatty acid (MUFA) rich olive–pomace oil (OO) to enhance its stability. CNO contained a total of 91.3 % of SFA, while OO had oleic acid, C18:1 (74.3 %) as MUFA. Two blends of NSO with CNO and OO, i.e. NSO + CNO(B) and NSO + OO(B), were prepared in the ratio of 1:1. The blends were further interesterified using the lipase enzyme from Rhizomucor meihei and interesterified oils, i.e. NSO + CNO(I) and NSO + OO(I), were obtained. The oxidative stability of the oils was evaluated by incubating them at 37 °C and 55 % relative humidity (RH) for a period of 45 days. The peroxide values of NSO + CNO(B), NSO + OO(B), NSO + CNO(I) and NSO + OO(I) showed a reduction by 53.3, 42.6, 65.3 and 55.4 %, respectively, while the conjugated diene values showed a reduction by 75.0, 66.9, 76.7 and 75.3 %, respectively, as compared to NSO during the incubation period. This is probably the first report on the stability improvement of niger seed oil through blending and interesterification.