With kind permission by the Dean and Chapter of York Minster.

With kind permission by the Dean and Chapter of York Minster.

Did You Know…

…that the Creaminess of Chocolate Can Be Measured?

Chocolate brings a little bit of luxury into everyday life. It has not lost any of its seductive allure over the centuries. Not even strong-willed people can resist its effects, as tellingly shown by the film"“Chocolat,” in which sweet creations cast a spell over an entire provincial town.

This taste sensation is the product of a rather ordinary, though complex, manufacturing process. The cocoa beans have to be fermented and roasted, after which the cocoa mass is ground up and finally conched. How smoothly the finished chocolate melts and how it feels in the mouth is already determined by the grinding process. Even tiny particles can be detected by the human tongue; therefore, the finer the consistency, the creamier the end product.

In order to achieve optimal results, the chocolate mass is pressed through a system of rollers at different temperatures and speeds. The pressure on the mass is continuously increased so that by the end of the process the particles are so small that the coating on the metal cylinders is only 20 micrometers thick. Even on this order of magnitude, tastes still vary greatly. The Japanese prefer chocolate with a particle size of 11 micrometers, with the Swiss permitting 16 and the Americans even up to 20 micrometers.

A ZEISS spectrometer makes it possible to determine the coating thickness of the chocolate and thus the particle size right down to the micrometer in contactless operation during the grinding process. The reflectance of the mass in relation to the wavelength is measured in the near infrared range (950 to 1700 nanometers) to obtain the specific reflection spectrum. Continuous, second-by-second measurements allow every step of the grinding process to be monitored very closely. So the taste sensations that lie in store for chocolate lovers are already determined during production.

18 April 2012