Starch analysis: Brabender launches quicker and precise viscometer

05 Aug 2019 --- Laboratory equipment manufacturer Brabender is releasing a new viscometer, touted as being able to deliver rapid and straightforward measurements. ViscoQuick uses an integrated heating and cooling feature to reduce error rates in measurements, as well as having a new taring and calibration system. The device is to be marketed worldwide and can be used for starch-based products, as well as a diverse range of viscous and pasty masses.

“In contrast to the previous Brabender viscometers, the new device is an all-in-one device. Therefore, the heating and cooling device, as well as the software control, had to be realized differently than before,” Jessica Wiertz, Head of Food Application Lab at Brabender, tells FoodIngredientsFirst.

“The device had to become more compact, without a measuring tower that could be raised and lowered. Heating and cooling are now via Peltier elements, a small computer with pre-installed MetaBridge software, which is already integrated into the ViscoQuick. The paddle rotation is no longer implemented from above but instead is from below, so that a measuring tower is no longer required. A touch screen for easy control can also be attached to the device,” she continues.

The new device is compact but has the advantages of larger machines. Ulrike Ito, Product Manager (Food) at Brabender, notes that ViscoQuick is also user-friendly thanks to its Brabender MetaBridge software. All users can access any instrument or even operate several instruments at any time in the web-based system. 

Furthermore, gelatinization measurements can be reduced to ten minutes, due to quick heating (20°C/min) and cooling rates (15°C/min). Small sample sizes of between five and ten grams are required. The paddle and sample pot are easily exchangeable and do not have to be calibrated specifically for one instrument. They are also stainless steel to allow for easy cleaning and usage with bases and acids.

This device joins two prior viscometers in Brabender’s range. The Viscograph-E, provides reliable information about the gelatinization behavior of starch products. A measurement with this device takes one hour and 40 minutes according to the International Association for Cereal Chemistry standard. With its successor, the Micro Visco-Amylo-Graph (MVAG), it is possible to carry out a gelatinization measurement within 20 minutes, thanks to faster heating and cooling rates of 7.5°C/min.  

However the measurement results can deviate from time-to-time compared to the viscograph measurements, depending on the sample material used, Wiertz notes.

“The ViscoQuick closes this gap. The measuring time takes approximately 10-15 minutes, depending on the sample material. In addition to the small sample size, faster heating and cooling rates are also possible, while at the same time, good reproducibility is ensured.”

The need to monitor viscosity
The device can be used for quality control of raw materials. Due to the flexible test parameters, manufacturing and processing processes of starch and starchy materials can be more accurately simulated and, if necessary, optimized for the raw material, notes Ito. Some raw materials it can be used on include baked goods, noodles, confectionery, and gourmet foods, for paper, textiles, and even chemical and cosmetic products.

Ulrike Ito and Jessia Wiertz of Brabender.Checking viscosity can be a critical part of quality control in various sectors, as well as being useful in inspecting incoming and outgoing goods, production monitoring, and also for the development of formulation and manufacturing processes.

As natural products like starch have fluctuating viscosity due to their variety, cultivation and weather, it is necessary to determine what gelatinization properties the starches have. “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,” adds Ito.   

Additionally, 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 need to be fulfilled by laboratories, where they take up processing capacity. In this case, the reproducibility of the results also plays a role, notes Wiertz.

“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,” she concludes.

By Katherine Durrell