The company “Nuevas Tecnologías Espaciales” (NTE) developed the Electrical Impedance Spectroscopy (EIS) technology as a part of a project of the European Space Agency (Biological Life Support: Control of Immobilised Cell Culture) whose results were presented in a previous SAE paper (1). Electrical impedance spectroscopy consists on the measurement of electrical impedance at different frequencies and allows to measure on-line viable biomass in industrial fermentations. Another recent SAE paper (2) described the evaluation of the technology to be used in an industrial plant.
NTE has designed and evaluated a system to monitor yeast culture in the production process of the company Freixenet. Freixenet produces a drink called “CAVA”. CAVA is a type of alcoholic drink that results from a double fermentation process. This system is necessary to monitor the amount of viable yeast that is produced for the second fermentation process.
The monitoring system consists of 22 biomass measurement probes that allow real time monitoring of the whole fermentation process. The system determines the viable yeast cell population content of 22 tanks from the start of the fermentation (3 Million cells/ml) up to the maximum biomass content in the process (20 Million cells/ml). The measurement can be as fast as one second, allowing the cultures to be monitored continuously. The system has demonstrated good reliability in monitoring the fermentation process, being used presently in Freixenet facilities as a production and quality control tool.
This technology transfer is an example of the benefits that the Space research can provide to the industry. The technology was developed to measure automatically in-orbit biomass content in bioreactors (1). The European Space Agency promoted an evaluation project that led finally to the installation of an industrial system in Freixenet.
The monitoring system can be used in any fermentation process, such that, for instance, wine, beer and champagne production can benefit as well from this Space technology.