Ingrid Sumeri

Ingrid Sumeri

Competence Center of Food and Fermentation Technologies, Estonia

Title: Human gastrointestinal tract simulator for viability testing of bacteria


Dr. Ingrid Sumeri has completed her PhD at Tallinn University of Technology in the field microbiology and fermentation technology in 2011. Since 2005, she is project manager at Competence Center of Food and Fermentation Technologies. This center was founded in 2004 by Tallinn University of Technology and six companies for carrying out research in the food and fermentation technology. Ingrid and her research group develop and evaluate the strategies of probiotics production and incorporation into food to improve the survival of probiotics in gastrointestinal tract. Several articles on given topic have been published in peer reviewed journals.


The viability of probiotics is a key parameter for developing probiotic foods. To demonstrate the viability of probiotic bacteria in vivo, especially in humans is very complicated. Although the ultimate model for testing this is the human being, this ‘‘model’’ has various drawbacks, such as ethical constraints, high costs, and limitations in sampling from the gut. Therefore in vitro testing system, with quick results and reasonable handling expences, could be an attractive solution. The single bioreactor gastrointestinal tract simulator (GITS) was developed in Competence Center of Food and Fermentation Technologies to evaluate the probiotic potential of food. This model is able to imitate the conditions of the human upper GI tract – stomach and small intestine. Simulated parameters are temperature, pO2, pH, HCl secretion control in stomach, bicarbonate and bile secretion control in small intestine and the holding-time of food in upper gastrointestinal tract. Advantage of our single reactor simulator is the relative simplicity compared to multireactor GI dynamic models. GITS can be adapted to a wide range of target groups, such as babies, elderly people or individuals with gastrointestinal diseases. So far the simulator was used to study different commercially available and potential probiotics, natural consortia from food, and the effect of food matrix. A valuable experience on evaluating different methods of pretreatment of bacteria for the use in the food production processes with maximum health benefit was accumulated.