The Effect of Shearing in the Thermo-mechanical Properties of Candelilla Wax and Candelilla Wax–Tripalmitin Organogels

Abstract

We investigated the shearing effect in the thermo-mechanical properties of candelilla wax (CW) and candelilla wax-tripalmitin (CW-TP) organogels developed using safflower oil as the liquid phase. A shear rate of 600 s −1 was applied during cooling (1°C/min) of 3% CW and 3% CW-1% TP solutions, until reaching nucleation (i.e., 47°C) or metastable conditions (i.e., 52°C) then allowing the development of the organogel under quiescent conditions at 15°C. The thermal and rheological properties of these organogels were compared with the ones of organogels developed under static conditions. The X-ray results showed that under static conditions the CW crystallized in an orthorhombic O ? ð Þ subcell packing with a lateral stacking with a length (L) equivalent to the hydrocarbon chain's length. During organogelation of the 3% CW-1% TP solution, CW and TP co-crystallized in a O ? subcell packing with TP in a 2L stacking organization. The application of shearing did not modify the molecular packing of the crystals or the melting properties of the organogels. However, the CW and CW-TP organogels developed with shearing showed the formation of larger crystals (i.e., fiber-like or plate-like) in comparison with the ones developed under static conditions. The presence of 1% TP increased the solid fat content, and thus the CW-TP organogels showed higher elasticity (G′) than CW organogels. The organogels developed with the application of shearing until reaching metastable conditions (i.e., CW 52°C and CW-TP 52°C) had the highest G′ and yield stress of all organogels investigated. In the same way, creep and recovery analyses showed that CW 52°C and CW-TP 52°C organogels had the highest resistance to deformation, lowest instantaneous recovery, and highest extended recovery of all organogels studied. We concluded that application of shear and the extent of its application as a function of supercooling determine crystal size and the proportion of transient to junction zones throughout the three-dimensional crystal network and, therefore, the organogels' rheological properties.

Structure and Stability of Fish Oil Organogels Prepared with Sunflower Wax and Monoglyceride

“…In recent studies showed that the main peaks of the MG organogel systems were 4.50, 24.00 and 46.00 Å 8,9 . Similar results were obtained in our study 13 , these peaks were related to the β form polymorph of TAGs. Interestingly, the results from the organogel XRD peaks at 3.82 and 4.18 Å were found to be similar to β form Table 3 .…”

“…SFC values show the rates of solid content of oils and fats at different temperatures. Moreover, SFC values are indicators of the changes in consistency and plasticity of food products and therefore SFC values are essential measurements in bakery, confectionery and margarine in- Table 1 The color values (L, a* and b*) oil binding capacity (OBC), crystal formation time (CFT) and solid fat content (SFC) of the fish oil organogels developed with MG and SW. 13 reported that the SFC value of the safflower organogel prepared with 3 CW was 2.25 . These results are in line with our findings.…”

Physical Properties of Candelilla Wax, Monoacylglycerols, and Fully Hydrogenated Oil Oleogels

“…A similar reduction in enthalpy in mixtures of structuring agents was reported in other studies (Bin Sintang et al, ). This cocrystallization could occur through molecular interactions between the aliphatic chain of hentriacontane (a n‐ alkane with 31 carbons), the major component in CLX, and the long‐chain fatty acids (stearic and behenic acids) found in MAG and HF (Chopin‐Doroteo et al, ; Toro‐Vazquez et al, ).…”

“…Previous studies have shown that MAG‐based oleogels showed a structure recovery above 50% or less depending on the MAG used (Bin Sintang et al, ) while CLX oleogel presented 21.78% of thixotropic recovery (Doan et al, ). Moreover, the addition of tripalmitin (PPP) to CLX oleogel increased the overall resistance to deformation of CLX (Chopin‐Doroteo et al, ). Our results show that the hysteresis effect of CLX‐based oleogels can be reduced by adding other structuring molecules such as MAG and/or HF.…”

Physical Characterization of Wax/Oil Crystalline Networks

“…Several researchers have studied the crystallization behavior of waxes and vegetable oils. Research in this area has included the evaluations of crystallization in vegetable oils with rice bran wax (Dassanayake and others , ; Hwang and others ; Blake and others ), candelilla wax (Toro‐Vazquez and others , , ; Morales‐Rueda and others a,b; Chopin‐Doroteo and others ; Alvarez‐Mitre and others ; Barbosa Rocha and others ; Blake and others ), beeswax (Mellema ; Hwang and others ), and sunflower wax (Hwang and others ; Blake and others ). In addition, some research has been performed on the use of sunflower wax to structure semisolid materials such as milk fat (Martini and others ; Kerr and others ).…”