Dynamic control of polymorphic transformation in triglycerides by surfactants: The button syndrome

Abstract

The kinetics of polymorphic transformations in monoacid saturated triglycerides and the influence caused by the presence of certain solid surfactants were investigated. Selected emulsifiers can be incorporated at the level of 10 wt% within the triglyceride, without changing the crystal lattice; on the other hand, their presence affects the heat capacity of the triglyceride and the NMR relaxation time T1. Following the polymorphic transformation both during aging and during heating in the DSC, it was observed that both the mechanism and rate of transformation of the triglyceride strongly depend on the kinetic conditions and on its own chemical structure. In conjunction with these results it also was observed that the effect of the emulsifier is strongly dependent on the transformation conditions. The kinetic effect of the additive on the solid‐solid transformation has been found to be strictly associated with its hydrophilic moiety structure; a model of molecular incorporation has been proposed which describes the arrangement of the surfactant molecules parallel to the triglyceride chains and formation of vacancies. The selectivity of the additive concerning its effect of dynamic controller of polymorphic transformations has been explained by its capacity to create hydrogen bonds with the neighboring triglycerides, which was called the “Button Syndrome.” The wide range of different additives and triglycerides used supplied a better understanding of the factors which determine the polymorphic and crystallization behavior in triglycerides.

Structural characteristics of crystals formed in palm oil using sorbitan tristearate and sucrose stearate

“…In this process, emulsifiers can modulate the polymorphic transformations in the solid state or via the liquid state, controlling the physical state of crystals and extension of the mobility of the molecules, thereby regulating the rate of polymorphic transformation. [45] Accordingly, STS contributes to the formation more stable polymorph in PO, as β′ crystals.…”

“…[43] According to Rousseau et al, [44] the ability of the emulsifier to prevent the transition to the β form not only depends on the particular chemical structure but also on the structural adjustment, which affords the interposition of the additive between the fat molecules, thereby minimizing the defects, and forming hydrogen bonds between the functional groups. [45] In this context, the addition of 5% of STS is enough to the organization of the TAGs of the PO in the most stable orientation.…”

Effect of Glycolipid Fraction on Fat Bloom in Dark and Milk Chocolates.

“…There have been attempts to prevent fat bloom by, for example, improving the process for producing chocolate (Hachiya et al, 1989a, b), adding a substitute fat which is highly compatible with cocoa butter (Lohman & Hartel, 1994) and adding an emulsifier as a fat bloom inhibitor (Aronhime et al, 1988, Suwa & Matsuda, 1993.…”

“…Some emulsifiers are known to be useful agents to control the polymorphic behaviors of fats and oil (Kawamura, 1980;Aronhime et al, 1988).…”

Physical properties of fats in food

“…Emulsifiers are added to chocolate fats to modify the rheological properties so that interactions between fat crystals, hydrophilic particles such as sugar and milk powders and water phases are mediated through the emulsifiers (Katsuragi, 1999). The emulsifiers also affect fat bloom stability, acting at growing crystal surfaces of cocoa butter (Aronhime et al, 1988). The addition of high-melting fats having the same crystal structure as Form V, namely form β 2 of 1,3-dibehenoyl-sn-2-oleoyl-glycerol (BOB), is quite effective in crystallising cocoa butter in Form V without the need for tempering (crystal seeding; Hachiya et al, 1989aHachiya et al, , 1989bKoyano et al, 1990).…”