Crystalisation IV

Under economic point of views a fast crystallization of chocolates is necessary to guarantee high production speed. Therefore tempering machines and cooling tunnel need to be set to the optimal conditions. Only ideal crystallization gives products which are stable against fat bloom. Despite the already gained knowledge of pre-crystallization there are still uncertainties and problems due to unsteady product qualities of the cocoa butter. It is well known, that cocoa butter and masses of different origins may show different crystallization behavior. The project “cocoa butter” could show that minor components may have a big influence on the physical properties of cocoa butter, cocoa masses and chocolates. The proposed methods were harmonized and a new NMR-method was developed in the previous IVLV-Projects “crystallization” I-III. Until now, unspecific cocoa butter samples were used to develop and establish the measuring methods. In 2016 cocoa butter samples were specifically treated and analyzed. In the subsequent project these trials will be extended by varying storage conditions. The methods established and developed in the previous projects will be used for further cocoa products.

Goal:

Different methods for measuring crystallization behavior of cocoa butter have been established in the chocolate industry. These methods should be compared in a cooperative test to show their abilities also on cocoa masses. The comparability of the results between different laboratories and the reproducibility will be investigated. Project partners will have the chance to compare notes and discuss different measuring methods and to optimize the scheme of measuring.

Fraunhofer IVV will provide homogenized and standardized samples for the measurements (For example cocoa butter of different origins (Bahia, West Africa, mixture of cocoa butter and milk fat)), sends the samples do the participating laboratories and makes the evaluation of the different results. At the organized meetings at Fraunhofer IVV methods and recommendations will be derived.

Used Methods:

• DSC (isotherm and with cooling rates)
• Micro DSC
• Multitherm (Bühler)
• Shukoff cooling curves
• NMR (solid fat content, dynamic quasi-isothermal crystallization)
• Rheometry

Beside the development of crystallization indices for static methods, dynamic methods for analyzing cocoa masses and chocolates will be in the focus of the project.