Mondelēz International-owned Cadbury filed a patent for temperature tolerant chocolate in November 2012. Nestlé filed its own patent shortly afterwards and now Mars has developed its own method.
Mars’ process involves adding a polyol - preferably glycerin - and a thermal structuring component such as a monosaccharide like dextrose to the formulation.
Overcoming refrigeration problems in hot countries
“With a sharp melting point very near 37°C, cocoa butter provides the desirable melting profile upon ingestion, and thus, a large component of the desired overall consuming experience,” said Mars in its patent application.
“However, what is a desirable trait from a consumer's perspective is not necessary a positive attribute from a manufacturing, shipping and/or handling perspective.”
It said that that chocolate’s quick melt was a quality and storage problem in countries with temperatures averaging at or above 37°C. “These concerns may be exacerbated in regions where economic circumstances are not conducive to the wide spread use of refrigerated storage,” it said.
Taste: ‘Not significantly different’
Mars has developed a polyol and monosaccharide pre-mix that is added before chocolate molding to make white, milk or dark chocolate more temperate tolerant.
“The taste profile of the heat resistant fat based confection is surprisingly not significantly different from that of a conventional fat based confection,” it said.
Enhanced with multilayer packaging
According to Mars, multilayer packaging from foil or flow wrap layers would enhance the heat resistance of the chocolate.
“Generally speaking, the confections packaged in packaging with multiple layers were more stable, and exhibited less sticking to the packaging than those confections packaged in a single layer package,” said Mars, based on tests at 38°C.
Mondelēz and Nestlé methods
Cadbury’s method involved re-refining the chocolate after the conching step. It found that re-refined Cadbury Dairy Milk’s placed in an incubator at 40°C for 3 hours did not melt and had the same mouthfeel as a traditionally processed bar.
Last year, Nestlé’s R&D subsidiary Nestec developed its version by adding little or no sugar or polyols to the chocolate core and instead adding the humectant liquids to a “tropicalized shell” for the product.