Bloom formation on chocolate surfaces and texture softening due to migration of filling components are the main reasons for limited storage stability of filled chocolate products. The practical tests of such stability are quite time consuming because of the very long storage times of 6 months and more. Therefore, forced storage tests are applied to reduce the required time to detect possible quality changes. So far, these tests enable only relative data about stability. An extension of results found in these tests to a storage under ‘normal’ conditions is not possible.
The idea of the project is to use available models which describe the microstructural processes within the chocolate for prediction purpose. If these models reflect the reality in a sufficient way, they should also be able to predict storage stability at different conditions. The forced storage tests, however, have to be specially designed to obtain results which will enable an accurate calculation of all relevant model parameters.
Depending on type of chocolate and filling, suitable forced storage tests will be developed and tested which will deliver suitable data for the prediction task with minimal effort. Fat-based fillings as well as aqueous and alcoholic fillings will be included in the project. In a first project step migration models together with all relevant data will be gathered, evaluated and selected for the project. Changes in the chocolate during forced storage without contact to the filling will be characterized in a second project step. In the following project steps 3 and 4, the effects of different types of fillings on chocolate properties will be investigated in forced storage tests. Based on the measured data, model parameters will be calculated and checked. In the last project step, the models will be used to predict storage stabilities of filled chocolate products at non-forced conditions.
The IGF project presented here by the Research Association of the Industrial Association for Food Technology and Packaging (IVLV e.V.) is funded by the Federal Ministry for Economic Affairs and Energy via the AiF as part of the program for the promotion of industrial community research (IGF) based on a decision of the German Bundestag.