New imaging techniques are being developed that could be used to monitor the onset of the common and costly problem of chocolate bloom – and confectionery manufacturers are being invited to pioneer the process.
Previously methods to delay the emergence of fat bloom have included adding full cream fat powder to milk chocolate but problems frequently arise as the bloom is often undetected until it is too late – 24 to 36 months after production.
Chocolate bloom can occur in two forms, fat bloom and sugar bloom. Sugar bloom occurs when chocolate is stored in damp conditions and can be easily avoided by manufacturers following correct storage procedures and guarding against fluctuations in temperature.
Fat bloom is a consequence of changes in the fat structure of the substance and can be caused by inadequate cooling processes or the presence of soft fat centres in the chocolate. It frequently results in significant product losses for confectionary manufacturers as, although it does not affect the taste, the tell-tale sign of the bloom – a white frosting – is unacceptable to consumers.
Now researchers at the Institute for Surface Chemistry in Sweden, (YKI) have developed technology allowing them to map the surface of chocolate more effectively and are calling for manufactures to work with them in testing its application in the confectionery industry.
Becoming enrolled on the study at the Chocolate Research Centre will cost large companies €15,000 per year, small companies (those with less than 250 employees) will be charged €7,500 per year and micro companies (with less than 50 employees) must pay €3,750 for the year. Institute members will be able to benefit from a discounted price.
There will be quarterly bulletins issued of the progress made and steering committees will be complied in order to determine the direction research will take.
At present, the Centre intends to focus on structures in chocolate, mechanisms of bloom formation, oil migration mechanisms and recrystallisation in chocolate.
With atomic force microscopy (AFM), environmental scanning electron microscopy and profilometry, YKI have been able to measure surface structures and transformations at different microscopic scales more quickly than techniques used by the industry are able to do so at present.
AFM involves passing a probe over the surface area of the chocolate which then deflects as it detects variations and alerts operators to subtle changes in the chocolate's composition. Scientists can therefore catch and track the early onset of fat bloom, going some way towards eventually discovering more effective ways of eliminating it.
Area Manager for Fat Technology at YKI, Dr Paul Smith, told bakeryandsnacks.com: “We have been using different techniques on imaging and surface environment scanning to look at images of chocolate surface structure and changes that occur very early on in chocolate bloom.”
He added: “Detailed study in this area is important, hopefully in the future it will be of wider application in the food industry. It is a great opportunity for the industry to be involved in research.”
YKI are hoping to enlist from five to nine manufacturers and aim to begin the project by January 2007. Participating companies will be able to combine their own product development ideas and specific ingredients needs with research on soft surface structure and composition.
By Catherine Boal