Physical stability of model emulsions based on ethyl cellulose oleogels

Abstract

The purpose of this study was the evaluation of the physical stability of low-fat oil-in-water model emulsions containing oleogels based on ethyl cellulose), compared to emulsions with anhydrous milk fat. The oleogels were prepared using rapeseed oil with ethyl cellulose at the level of 4.5, 5.0, 5.5 or 6.0% w/w. The O/W emulsions (30/70 w/w) were stabilized by guar gum (0.6% w/w) and soy lecithin (5.0% w/w). The physical properties of oleogels and anhydrous milk fat (centrifugal stability, spreadability/penetration test), rheology and the physical stability of the emulsions (MS-DWS method, centrifugal/thermal stability) were determined, a storage test of the emulsions (CSA method, LUMiSizer) was also conducted. It was demonstrated that ethyl cellulose is an effective edible oil structuring agent. The increase in ethyl cellulose content enhanced the centrifugal stability and hardness of the oleogels. As a result of a microrheology analysis, it was found that the emulsion with anhydrous milk fat had the most elastic strength, macroscopic viscosity and the highest solids content. All emulsions demonstrated high centrifugal/ thermal stability. A higher temperature and extended storage time caused a reduction in the stability of all emulsions and increased the velocity of particle migrations. The ethyl cellulose-oleogels are potential fat phases for stable O/W emulsions, which could be used as a vegan alternative to traditional products based on animal components. K e y w o r d s: oleogels, ethyl cellulose, oil-in-water emulsions, MS-DWS method, storage test, CSA method

Solid Fat Replacement with Canola Oil-Carnauba Wax Oleogels for Dairy-Free Imitation Cheese Low in Saturated Fat

“…Through oleogelation, liquid vegetable oil can maintain a self-standing solid structure, although it contains a lot of unsaturated fat. Oleogelation is essential for solidifying liquid oil, and various materials such as natural waxes, fatty acids, polymer agents, and emulsifiers have been utilized to generate oleogels [22][23][24][25]. Among the diverse oleogelators, waxes such as rice bran wax and carnauba wax have been extensively used in a number of preceding studies because of the advantages of affordable cost, availability, and being Generally Recognized as Safe (GRAS) [26,27].…”

Application of Oleogel and Conventional Fats for Ultrasound-assisted Obtaining of Vegan Creams

“…It can be assumed that the high physical stability of the comparative sample was related to the presence of carrageenan as a stabilizing substance in its composition Table 1 . In other studies 27 , low-fat O/W emulsions containing lipids structured with ethyl cellulose, stabilized with soy lecithin 5.0 w/w and guar gum 0.6 w/w , were characterized by comparatively high stability to the control sample 30 g milk fat as fat phase per 100 g emulsion -the value of the total instability index was 0.001-0.004 after 24 h 20 from their production. In emulsions with oleogels, the flotation creaming mechanism of fat phase droplets mainly occurred, while in the control sample, the phenomenon of sedimentation of particles with a higher specific weight than fat progressed.…”

“…After centrifugation, the tubes were inverted for 30 min to remove the released oil. The centrifugal stability of fats was calculated based on the following slight modified equation 16,27 .…”

“…The microrheological characteristics of creams were analyzed according to our previous research 27 . The Rheolaser Master Formulaction, L Union, France was used and it operates using the dynamic multi-speckle diffusing-wave spectroscopy technique MS-DWS .…”

“…The physical stability of creams was also determined based on our previous studies 27,30 . The LUMiSizer 612 dispersion analyzer LUM GmbH, Germany was used.…”