Chocolate is one of the world's many favorites when it comes to sweets. The confectionary dates back by not only decades or centuries but even by millennia as the earliest evidence of chocolate was found to date back to 1900 BC.
Researchers started studying a 140-year-old mixing technique. They later revealed the science of what makes good chocolate.
The scientists have uncovered the physics behind conching, a process that is responsible for treating the distinctive smooth texture in chocolates.
The importance of this research, the scientists explained, is the possibility of producing confectionary with lower fat content. This could promote energy efficiency in chocolate manufacturing.
In 1879, Rodolphe Lindt, a Swiss confectioner, developed the conching process, which involves mixing ingredients for several hours. Edinburgh researchers studied mixtures resembling liquid chocolate that was created using the age-old process.
The research involves measuring the density of mixtures and observing how each mixture would flow at various stages of the process. Their study suggests that conching may alter the physical properties of granulated ingredients in the chocolate, especially the microscopic sugar crystals. Still, the science behind the process has not been fully uncovered.
However, the new research reveals that the process produces small molten chocolate by breaking down lumps of ingredients into finer grains. This then reduces the friction between the particles producing a smooth texture.
Prior to the practice of conching, the ingredients had rough, irregular clumps which do not flow smoothly when mixed with cocoa butter, thereby producing chocolate with a gritty texture.
The scientists pointed out that the research is important not only for producing better chocolate but also for improving processes used in other sectors. Citing some examples, the scientists explain that ceramics manufacturing and cement production could benefit from this research as well because their industry relies on the mixing of powders and liquids.
The study is a collaboration work between the scientists from Edinburgh and researchers from New York University. Mars Chocolate UK and the Engineering and Physical Sciences Research Council funded the work done in Edinburgh.
Professor Wilson Poon, from the school of physics and astronomy, is optimistic that the research can help reduce the amount of energy used in the conching process and would lead to greener manufacturing of chocolate. The professor added that by studying chocolate making, new insights into the physics of how complex mixtures flow have been uncovered. The research is one great example of how physics can build bridges between different disciplines.
