Impacts of Bleaching and Packed Column Steam Refining on Cocoa Butter Properties

摘要

Natural and alkalized cocoa butters were bleached and subsequently steam refined in a continuous packed column at temperatures ranging between 160 and 220 °C. None of the processes evaluated gave rise to any detectable formation of trans fatty acids, interesterification or polymerization. For the pressures and steam injection rates used, packed-column steam refining required a minimum temperature of 170 °C to achieve acceptable taste. Bleaching was highly effective in preventing darkening at high steam-refining temperatures, as well as in removing alkaloids, such as theobromine and caffeine, before steam refining. The impacts on the crystallization properties of cocoa butter were studied using DSC and P-NMR. The more significant changes in crystallization kinetics and equilibrium values can be reliably predicted on the basis of FFA removal from the butter.