Development of an extraction protocol for the removal of the fat phase within chocolate

- We extract the continuous cocoa butter phase from nonfat dispersed particulates.
- Small amounts of added water during tempering stabilizes the particulate network.
- Without added water, defatted chocolate cannot form a self-supporting structure.
- Adding water allows the removal of 88% fat without loss of structural integrity.

An extraction method to remove the cocoa butter fat phase from chocolate while leaving the dispersed particulate network intact was developed. Three parameters were evaluated: i) the method of addition of small amounts of water to the chocolate during its preparation; ii) the contact method of a solvent (petroleum ether) with the fat phase; and iii) the duration of fat phase extraction. The addition of water was necessary to retain the structure of the backbone particulate network during extraction. The absence of water resulted in dispersed particulates that fell apart, suggesting that the water aided in network preservation. Water in the form of an emulsifier-stabilized water-in-oil emulsion was the most efficient means of addition. Optimal fat extraction and structure retention were achieved with a combined capillary/vapor phase method. Extraction times upwards of 24 h were necessary to extract sufficient cocoa butter from the chocolate for particulate network analysis. Characterization with scanning electron microscopy and confocal microscopy confirmed the adequacy of the developed extraction method and demonstrated that the backbone structure consisting of dispersed particulates could be made into a self-supporting network.