Journal of Oil Palm Research Vol. 35 (1) March 2023, p. 23-32
STABILITY AND PHYSICAL PROPERTIES OF DIHYDROXYSTEARIC ACID BASED ORGANOGELS IN DIFFERENT TYPES OF VEGETABLE OIL
Received: 12 August 2021 Accepted: 2 March 2022 Published Online: 22 April 2022
Dihydroxystearic acid (DHSA) was obtained from epoxidation and hydroxylation of oleic acid from palm oil. Unlike monohydroxystearic acid, only a few publications described DHSA in the gelation of oils. This study aimed to investigate the stability and physical properties of DHSA organogels in different vegetable oils. Five vegetable oils; refined, bleached and deodourised palm olein (RBDPOo); refined, bleached and deodourised super olein (RBDSPOo); refined, bleached and deodourised palm kernel olein (RBDPKOo); medium-chain triglyceride (MCT); and soybean oil (SBO) were used to prepare DHSA organogels. The stability and critical gel concentration (CGC) of organogels were determined at concentrations of DHSA in the range of 0.2%- 20.0% (w/w). DHSA organogels were characterised using a polarised light microscope, texture analyser and rheometer. DHSA organogel with RBDSPOo showed a more stable gel with the lowest CGC value at 9.9% than other oils. In microscopic characterisation, DHSA organogel with RBDPOo showed a high density of small needle-like crystals. The hardness and rheological measurements revealed that DHSA organogels with RBDPOo and RBDSPOo showed the highest elasticity, which is more than 10 000 Pa compared to other oils. However, all DHSA organogels were classified as soft gels and have the potential to be used in cosmetic products.KEYWORDS:
1 Malaysian Palm Oil Board,
6 Persiaran Institusi, Bandar Baru Bangi,
43000 Kajang, Selangor, Malaysia.
* Corresponding author e-mail: firstname.lastname@example.org