Effect of different gelators on the physicochemical properties and microstructure of coconut oleogels.

BACKGROUND: The inherent properties of coconut oil (CO), including its elevated saturated fatty acid content and low melting point, make it suitable for application in plastic fat processing. The present study explores the physicochemical characteristics, micromorphology and oxidative stability of oleogels produced from CO using various gelators [ethylcellulose (EC), ß-sitosterol/γ-oryzanol (PS) and glyceryl monostearate (MG)] to elucidate the formation mechanisms of coconut oleogels (EC-COO, PS-COO and MG-COO). RESULTS: Three oleogel systems exhibited a solid-like behavior, with the formation of crystalline forms dominated by ß and ß'. Among them, PS-COO exhibited enhanced capability with respect to immobilizing liquid oils, resulting in solidification with high oil-binding capacity, moderate hardness and good elasticity. By contrast, MG-COO demonstrated inferior stability compared to PS-COO and EC-COO. Furthermore, MG-COO and PS-COO demonstrated antioxidant properties against CO oxidation, whereas EC-COO exhibited the opposite effect. PS-COO and EC-COO exhibited superior thermodynamic behavior compared to MG-COO. CONCLUSION: Three oleogels based on CO were successfully prepared. The mechanical strength, storage modulus and thermodynamic stability of the CO oleogel exhibited concentration dependence with increasing gelling agent addition. PS-COO demonstrated relatively robust oil-binding capacity and oxidative stability, particularly with a 15% PS addition. This information contributes to a deeper understanding of CO-based oleogels and offers theoretical insights for their application in food products. © 2024 Society of Chemical Industry.

A comprehensive foodomics analysis of rambutan seed oils: Focusing on the physicochemical parameters, lipid concomitants and lipid profiles.

A foodomics approach was employed to systematically characterize and compare the quality parameters, antioxidant activity, minor-components, fatty acid composition, and lipid profiles of the seed oils from the three most popular rambutan varieties in China. The total lipid content ranged from 23.40 to 25.77 g/100 g. The fatty acids 9cC18:1 (39.84%-40.92%) and C20:0 (28.45%-30.23%) were identified as the dominant ones, which are uncommon among higher plants. All oil samples exhibited low AI and TI values. BR-7 exhibited the highest levels of squalene (21.48 mg/kg), cholesterol (144.43 mg/kg), and tocopherol (17.42 mg/kg), and the lowest levels of polyphenols (24.21 mg GAE/kg). Additionally, a total of 807 lipid species were identified, with TAG, DGTS, and PE being the predominant ones. Multivariate statistical analyses revealed significant variations in lipid profiles among the varieties, particularly in glycerophospholipids and sphingolipids. Fifty-seven distinct lipids were identified as potential markers for distinguishing between rambutan varieties. Furthermore, a hypothetical scenario was developed by linking relevant lipid metabolism pathways. These findings establish a theoretical framework for comprehending rambutan seed oil in depth and unlocking its high-value potential.