Cellulose ether oleogels obtained by emulsion-templated approach without additional thickeners

Abstract

In this research, the suitability of methyl cellulose (MC) and hydroxypropyl methylcellulose (HPMC) as unique oleogelators (without additional thickeners) to obtain sunflower-based oleogels by emulsion template approach was investigated. For this purpose, different oleogels were designed taking into account the following variables: 1) the type of cellulose ether: MC or HPMC; 2) cellulose ether concentration (0.5, 1 and 2%); and 3) the oil concentration in the initial emulsion (47 and 60%). The texture, rheology, oil retention properties and microstructure of the obtained oleogels were compared and discussed. Results highlighted that stable structured oil systems can be obtained by using cellulose ethers. The most determining factor in the physical properties of the oleogels was the initial oil concentration and the hydrocolloid concentration, regardless of the type of hydrocolloid used (MC or HPMC). The increase in cellulose ether concentration provided harder oleogels with high mechanical strength, which was linked to more stable systems with enhanced oil binding capacity, reaching values up to 95%. On the other hand, the increase in oil in the initial emulsion decreased the quality of the systems, providing a softer structure with lower ability to retain the oil. The possibility to provide solid structure to sunflower oil by using MC and HPMC would be a promising approach to solid fat substitution in trans free and low saturated fat foodstuffs.