Miller Magazine Issue: 132 December 2020

74 ARTICLE MILLER / december 2020 ter this has ethical reasons, as milk is a high-quality fo- odstuff. However, to be as close as possible to cooking pudding as a final product, milk was used for a selected number of tests and samples in this study. It was initially assumed that all pudding mixes behave similarly in terms of cooking and cooling when water is substituted by milk. Test series 3: Analysis under variation of sugar addition Since the final product usually contains sugar, this inf- luence was also investigated. Again, it was assumed that the influence of sugar would be similar for all pudding mixes, so this was only performed on some samples. In addition, the time of addition of pudding mixes and sugar was varied during the measurements. In common laboratory measurements, all materials (liquid and solids) required for testing are added at the beginning. Since in the preparation of pudding, the powder, which is mixed with sugar and then dissolved with little liquid, is only stirred in when the main part of the milk is boiling, this influence on the viscosity was also considered. Two test arrangements were considered, whereby the sugar was always mixed with the pudding mix in a dry state (manufacturer's information), then stirred with cold liquid and transferred to the measuring cup. In va- riant one, all components (powder, sugar, milk) were already contained in the measuring cup when the experiment was star- ted. In contrast, 86 % of the milk was available at the beginning of variant two, which was heated at 20 °C/min. according to the specifications. After exactly 3 minutes, short- ly after reaching the 93 °C holding temperature, the solids mixed with the remaining milk (14 %) were added during the running process throu- gh an opening in the lid. During dosing, the speed of the paddle was auto- matically reduced to the programmed speed of 50 rpm, only to return to the original value after 1 mi- nute. In this study, however, the main focus was only on the different viscosities and the viscosity changes at the end point of the respective cooling to 50/20/6 °C, as only these consis- tencies - especially those at lower temperatures (20/6 °C) - are of interest from the consumer's point of view. For this purpose, two special profiles were developed in advance, which automatically enabled reproducible co- oling to 20 °C and 6 °C, respectively. The programmed cooling rates were between 15 °C/min. and 1.5 °C min., depending on the selected final temperature. RESULTS OF THE STUDY Test series 1: Analysis at different temperature profiles As already described, in the first test series all samples were measured with the parameters listed under ST-50 (Tab. 1). Due to the high heating and cooling rates possib- le with the ViscoQuick, the measuring time was reduced to 10 minutes compared to the frequently used methods. The sample mix for industrial use showed viscosities that were in some cases more than twice as high as the "su- permarket samples". The cause was identified as the much higher initial weight (approx. 35 %) specified by the ma- nufacturer. As a result, the weight was reduced to the 7.77 g specified for most products, which resulted in a much better comparability. However, the data were not consi- dered in the further course of the series, as all other mixes were used according to manufacturers' recommendations. Fig. 3: Test scheme