In a study, the measuring and testing system provider Brabender examined the cooking and cooling behaviour of commercially available vanilla puddings. In tests with the high-precision Brabender ViscoQuick viscometer, the influence of temperature, milk and sugar on the viscosity properties of the pudding was determined, and clear differences were shown.

By Markus Löns, Business Development Manager Food, Br

The consumption of vanilla pudding is very popular among the population of many countries and regions. This is shown by the large number of suppliers who offer a broad range of variants, divided into cold-produced products and those that need to be cooked. No wonder that even medium-sized discounters and supermarkets may have listed two to five different ready-to-cook vanilla pudding mixes suppliers.

The main ingredient of the mixes is starch, mainly made from maize. Furthermore, they contain table salt, aroma and colourings, partly real bourbon vanilla is added. Customers experience product quality parameters as taste, colour and consistency only with their senses. As this is very subjective, a study conducted by the Brabender company from Duisburg/Germany concentrates exclusively on one measurable quality parameter: viscosity. In addition to the already mentioned taste and colour, this is one of the main sensory properties and thus responsible for the popularity of vanilla pudding.

This study should examine the extent to which commercially available puddings differ in their consistency. Since the composition of these products is very similar in most cases and therefore only marginal differences were to be expected, the corresponding tests were carried out with a high precision viscometer, the Brabender ViscoQuick.

To obtain meaningful results – from the cooking behaviour of the stirred pudding powder to the condition of the pudding after cooling – data for the cooling behaviour were recorded in addition to the typical heating tests. The usual test methods in quality assurance as well as in research and development rarely consider a temperature reduction to below 50 °C. Therefore, a special focus was on viscosities at room temperature (RT-20 °C) and in a cooled state (FT-6 °C, refrigerator).

In further series of experiments, the influence of milk or sugar on the viscosity course should have been analyzed and considered. As both raw materials are used in the cooking of pudding, it makes sense to analyze the kind and extent of influence on consistency. Especially in the cooling phase from 20 °C to 6 °C, the differences between the usage of milk in contrast to water are interesting for the researcher, as these are likely to be reflected in the sensory properties of the finished pudding. The influence of sugar, on the other hand, could be of interest to the final consumer from a health point of view.

For the study, a total of ten different commercial pudding powders were purchased in supermarkets. In addition, a product manufactured for industrial use in the bakery industry was tested, but was not included in the evaluation because of its gelatinization and cooling properties, which deviated significantly from the other samples.

The Brabender ViscoQuick visco-meter used for the experiment has an integrated heating/cooling system that operates without an additional heating or cooling thermostat. Due to the high heating/cooling rates, the individual measurements could be performed in a relatively short time (10 min at 50 °C, 20 min at 20 °C and 25 min at 6 °C temperature). Due to the evaluation unit directly built into the device, necessary changes of the test parameters and correlations could be made without an additional PC. The necessary cooling profiles provided reproducible results.

The study found that the pudding powder manufactured for industrial use was very different from all other samples. One can only speculate about the reasons. All other patterns showed predominantly similar or equal viscosities. However, the change in the ranking (highest/lowest) of the individual pudding samples was remarkable when the final temperature was changed. There were samples that became firmer as they cooled down, others softer.

Since for the consumer not only colour and taste but also consistency can be a purchase criterion, measurements of up to 20 °C/6 °C as well as the effects of milk and sugar on the consistency of a vanilla pudding mix ought to be included in the focus of future product developments and quality controls. Measuring final viscosities at low temperatures of cooked pudding mixes can generate additional added value.

No qualitative assessments were made during the tests and evaluations. The aim was exclusively to point out and make visible any differences that may exist. The final assessment of the individual puddings is the sole responsibility of the con-sumer. It is left to the manufacturers of the various pudding mixes to draw their own conclusions from this study. The results of the study in detail can be found in a white paper released by the Brabender company (http://bit.ly/vqpudding-en).