End consumers have certain quality expectations for products which producers need to live up to. Viscosity measurements for raw materials and end products are analyses which need to be performed rapidly and reliably in the production process. For this purpose, the laboratory equipment manufacturer Brabender from Duisburg has developed the new ViscoQuick. Jessica Wiertz and Ulrike Ito from the Application Lab Food introduced the device in an interview.

Viscosity measurements are of key importance in many sectors, such as the food industry in the case of starch and starch-containing products. Why are they so important? UI: Measuring viscosity is necessary in order to control the quality of raw materials, to optimize and monitor the production process, and of course also for the final inspection of the finished product. This ensures that only the best raw materials are used and that complaints are minimized. Malfunctions and the resulting losses in production also need to be avoided. In addition, they are also used to develop products and production processes.

Which factors influence viscosity and hence the processing chain? UI: Natural products such as starch are subject to natural fluctuations, which depend on their type and variety, as well as their cultivation and weather conditions. Depending on their individual properties, they have a differing level of suitability for certain uses. Further on in the processing chain, temperature, quantity, heating and cooling rates, as well as shear forces acting on them, play a big role. By determining product-specific viscosity curves, the properties can be controlled and processes optimized.

JW: In order to determine the best possible use of a raw material and analyze its quality, the gelatinization properties of starches and starch-containing materials are examined. When processing flours, the effect of raw material-specific enzyme activity on the gelatinization process is also analyzed. It is also decisive for the processing properties of the flour and has a huge impact on the result after baking.

Which challenges do companies face overall, and in particular for the quality control of viscosity measurements? UI: Viscosity measurements are necessary in many industry sectors. Among other things, this also includes needing to inspect various materials within a single company. Hence, it is above all important that a device for viscosity measurement can be used flexibly enough to live up to the various requirements.

JW: The speed of the viscosity measurement and a reliable result are particularly important during production quality control. Because all raw materials need to be checked and the end products also need to be inspected, this means comprehensive analysis requirements which need to be fulfilled by laboratories, where they take up processing capacity. In this case, the reproducibility of the results also plays a role. The better the reproducibility, the less frequently measurements need to be repeated for confirmation. The factor of speed affects the entire production process. Because approvals for the use of raw materials or end products can only be issued after quality inspection by the laboratory, the entire production operation depends on the analyses. In a worst-case scenario, this results in disruptions and losses in production, or the quality of the end product does not adhere to requirements and entire production batches are unusable. Of course, this also costs companies money.

Brabender has now brought the ViscoQuick to the market, which promises to deliver rapid and straightforward measurements. How is it different from existing systems?

JW: First of all, the ViscoQuick is a device that can be used for various purposes. It can analyze starches, as well as viscous and paste-like masses. This means that the ViscoQuick is a device with a wide range of possible applications which covers many industry requirements. The ViscoQuick offers companies multiple advantages over existing systems, which range from measurement options to savings in terms of space, time, and costs, as well as in terms of the collection of measurement data.

UI: The ViscoQuick is a compact device which is also user-friendly. It is fitted with an integrated heating and cooling system, so that an external thermostat is not necessary. There is also the intelligent MetaBridge software from Brabender, which allows all measurement data to be evaluated, diagrams to be displayed, and applications to be saved. This makes the ViscoQuick a stand-alone device which not only saves space, but which can also be used independently of other devices.

What advantages does the system offer for viscosity measurements in practical applications? JW: The greatest advantage afforded by the ViscoQuick is the enormous amount of time saved during measurements. Compared to classic measurements for starch gelatinization, a measurement procedure is possible in approx. 15 minutes with the ViscoQuick. With the ViscoQuick, a heating rate of up to 20 °C/minute is possible, and a cooling rate of up to 15 °C/minute. Furthermore, the integrated heating/cooling feature also reduces any error sources in the measurements. The ViscoQuick also offers improved reproducibility with the new patented dynamic taring and calibration method and the new, precise heating/cooling system. This not only delivers reliable results, but also saves clients time, as repeated measurements are reduced. Another advantage is that, depending on the sample material, only small sample sizes of between 5 and 10 grams are required and that temperature ranges between + 10 °C and 98 °C can be achieved. Furthermore, the reusable sample containers and paddles are made of stainless steel, meaning that they can be cleaned easily and also be used for applications with bases and acids. This means that additional sample containers do not need to be bought, thereby providing a sustainable solution and saving on follow-up costs.

Which parameters can be measured with the device and which materials and/or applications is the device suitable for? JW: With the ViscoQuick, it is possible to determine the viscosity behavior of samples. During this process, the viscosity of a suspension is recorded via the rotating paddle during the entire measurement procedure. The MetaBridge software records a complete picture and supplies information on viscosity increases and the maximum viscosity. The ViscoQuick enables the analysis of starch gelatinization properties, qualitative determination of alpha-amylase activity in flours, and measurement of the absolute viscosity of Newtonian fluids.

UI: This makes the ViscoQuick suitable for a wide range of uses. It can be used to measure hot and cold viscosities and to check the stability of thickening and binding agents. It is equally suitable for testing the acid resistance of starches as well as for investigating alkaline gelatinization.