Comparative evaluation of structured oil systems: Shellac oleogel, HPMC oleogel, and HIPE gel

Abstract

In lipid-based food products, fat crystals are used as building blocks for creating a crystalline network that can trap liquid oil into a 3D gel-like structure which in turn is responsible for the desirable mouth feel and texture properties of the food products. However, the recent ban on the use of trans-fat in the US, coupled with the increasing concerns about the negative health effects of saturated fat consumption, has resulted in an increased interest in the area of identifying alternative ways of structuring edible oils using non-fat-based building blocks. In this paper, we give a brief account of three alternative approaches where oil structuring was carried out using wax crystals (shellac), polymer strands (hydrophilic cellulose derivative), and emulsion droplets as structurants. These building blocks resulted in three different types of oleogels that showed distinct rheological properties and temperature functionalities. The three approaches are compared in terms of the preparation process (ease of processing), properties of the formed systems (microstructure, rheological gel strength, temperature response, effect of water incorporation, and thixotropic recovery), functionality, and associated limitations of the structured systems. The comparative evaluation is made such that the new researchers starting their work in the area of oil structuring can use this discussion as a general guideline.Practical applicationsVarious aspects of oil binding for three different building blocks were studied in this work. The practical significance of this study includes (i) information on the preparation process and the concentrations of structuring agents required for efficient gelation and (ii) information on the behavior of oleogels to temperature, applied shear, and presence of water. This information can be very useful for selecting the type of structuring agents keeping the final applications in mind. For detailed information on the actual edible applications (bakery, chocolate, and spreads) which are based on the oleogel systems described in this manuscript, the readers are advised to refer our recent papers published elsewhere. (Food & Function 2014, 5, 645–652 and Food & Function 2014, 5, 2833–2841).

Rheological Profiling of Organogels Prepared at Critical Gelling Concentrations of Natural Waxes in a Triacylglycerol Solvent

“…However, since these gels are rather "weak" in nature with high shear sensitivity and low thixotropic recovery, incorporation of high-melting fats will be necessary to obtain structured oil systems (i.e., hybrid systems) with desired properties for actual food applications. 56 ■ ASSOCIATED CONTENT * S Supporting Information Chemical composition of waxes (Table S1); flow parameters of gels (Table S2); photograph of organogels ( Figure S1); chemical structures of main wax components ( Figure S2); plots of temperature ramps ( Figure S3); graph of tan δ at v = 1 Hz measured at periodic intervals for all gels over a storage period of 1 month ( Figure S4); and data from 3 ITT ( Figure S5). The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.-jafc.5b01548.…”

The Potential of Waxes to Alter the Microstructural Properties of Emulsion‐Templated Oleogels

“…[7] Many have shown potential, but waxes appear to be very promising. [7] Many have shown potential, but waxes appear to be very promising.…”

Nutritional Evaluation of Oleogel Made from Micronutrient Rich Edible Oils

“…Recently, some researchers have even demonstrated interesting food based applications of oleogelation such as replacement of solid fats and reduction of saturated fats in ice creams 15 , cooked frankfurters 16 , sausages and cookies 17 as well as for development of delivery systems of nutraceuticals. Three alternative approaches of oil structuring was done using wax crystals shellac , polymer strands hydrophilic cellulose derivative , and emulsion droplets as structurant in one study 18 . Another interesting study examined the physical properties of soybean oil oleogels and commercial confectionery filling fats and evaluated the oil migration properties in model praline systems.…”