Polymorphic Phases of Natural Fat from Cupuassu (Theobroma grandiflorum) Beans: A WAXS/SAXS/DSC Study

Abstract

The polymorphic phases of natural fat extracted from cupuassu beans were studied by performing in situ temperature-dependent X-ray scattering experiments and differential scanning calorimetry (DSC) using synchrotron radiation. Cupuassu (Theobroma grandiflorum) is a native plant of the Theobroma species originally found in Brazil's Amazon region, with a great potential for utilization in the chocolate industry. The experiments and data analysis were performed using as a reference the known polymorphic phase behavior of cocoa butter. The results led to the identification of cupuassu fat polymorphic crystalline phases.Using the nomenclature generally found in the literature fortriaceylclycerols(TAGs) systems, these phases were labeled γ, R, β 0 ,a ndβ in increasing order of melting temperature and stability. Differential scanning calorimetry measurements of fusion temperatures indicated the existence of two β states in cupuassu fat. These phases were labeled β2 and β1, following the aforementionednomenclature.Inspiteofthedifferentmeltingpoints,theexistenceofa β2f β1transitioncouldnotbeproven,due to the great deal of structural similarity of the corresponding X-ray patterns obtained in our experiments. A comparison of our resultswiththose reported for several purecompoundsandternary mixturesof TAGsindicated that these components are mainly responsible for the cupuassu fat phase behavior. This study provided the first experimental results of an in-situ follow-up of the polymorphic phasetransitions and crystallizationof fat from Braziliancupuassu beans, anindustrially important naturalproduct.