Katja Schulze
Oculyze GmbH, TH Wildau

MIKROBIOLOGIA
Słowa kluczowe: yeast, cellcounter, mobilemicroscope, concentration, viability

Concentration and viability of brewing yeast are the most important factors determining beer taste and quality. Incorrect pitching is responsible for the spoiling of the taste and the usage of new yeast for every batch can be expensive.

The traditional way to analyse yeast is to count and evaluate the cells manually with a laboratory microscope. This approach is very time-consuming, tedious and susceptible to human error. We developed a mobile microscope that can be used without specialized expertise. A combination of an optical module, a corresponding smartphone and automated image analysis, enables different cell counting approaches.

The whole system (containing hard- and software) is cheaper than other automated solutions. The device enables a 400x magnification with a high resolution of samples. The user can record and analyse microscopic images with the associated smartphone automatically. Data management and storage is carried out in the cloud and available from any internet connected device. The captured images are transmitted via a mobile network to the server and results appear on the screen within seconds.

The system was taken through an external validation by the Research and Teaching Institute for Brewing in Berlin. The concentration of the yeast cells is calculated by counting and the viability is determined by differentiating between dead and living cells with an appropriate staining solution (Methylene Blue or Violet). An accurate separation of clumped cells and the identification of budding occurrences make the results very precise.

With the results, the user has the option to use the integrated yeast pitch calculator that can directly determine the ideal pitch rate. To have a long-term overview of results, the user can also review all findings through a web application: that allows for generating customized reports, viewing historical data, tracking yeast over time and increasing statistical accuracy by creating averages of different measurements.