Development of in-line measurement methods to assess the quality of wheat dough during the lamination process
The lamination process has an important effect on the behaviour of dough during the next processing steps and, therefore, on the final quality of baked goods. Notably, during this process the creation of irregular surfaces (as for example surface cracks) should be avoided. Although various approaches exist for crack detection, their implementation on in-line measurement systems is still limited. To this purpose, a recent study conducted by a group of German researchers (Mahadevappa et al., 2015) proposed a solution based on the use of an automatic detection and evaluation system via digital images for the in-line assessment of irregular surfaces on laminated doughs. Surface quality of these products was evaluated in terms of cracks rate, i.e. the rate between the pixels of the cracks and the pixels of the global product surface. For the validation of this system different dough varieties were tested, as those for puff pastry. The results show that this system can detect the presence of even the smallest surface defect, even in unfavourable lighting conditions. Through the implementation of this simple technology, lamination can be optimised in terms of both, process severity (distance between the rollers) and dough recipe. According to the study, in order to maximise dough quality, the cracks ratio should always be below 0.1%. In conclusion, the researchers state that the developed system, although in need of further studies, offers interesting application potentials, especially for small and medium industries, considering the limited implementation costs.
Mahadevappa et al., Journal of Cereal Science, 64, 2015, 183-188