A food microbiome refers to the microbial community growing in a food product during its lifespan. The growth of such communities is affected by the nutrients contained in the product, its water concentration and acidity, as well as the additives used in its production, or any antimicrobial compounds contained in the product itself. The microbiomes of contemporary food products are also shaped by production processes, the cold chain and packaging solutions. Food microbiomes are directly linked to the shelf life and spoilage of food. During storage, the food microbiome goes through dynamic change, as a range of competitive settings prevail within the community. At the same time, mutual interrelationships lead to certain species becoming dominant (succession), as other species fade into the background, no longer constituting a significant part of the microbiome. At the department, we investigate the interaction taking place in food microbiomes to better understand why spoilage bacteria detrimental to food production gain dominance in the microbiome.
The adjacent image illustrates the foundation of the Distinguished Investigator project carried out at our department, with funding provided by the Novo Nordisk Foundation. We are looking for marker genes associated with microbiome growth, which are linked to perceivable changes in the properties of food products. The black curve depicts the growth of the microbiome during the product’s storage on the basis of a bacterial culture (microbial concentration per gram of food product). On the left, you can see a rapid growth stage, during which the perceivable quality of the food product is good, while the middle section shows a product in the process of being spoiled. The right-hand section of the chart illustrates a spoiled product. The image shows how the share of species in the microbiome changes over time and how the dominant functions on the surface change as the use-by date approaches. In addition, the gene activity of major metabolic pathways that regulate metabolism change as the microbiological contamination of the food product progresses. By identifying suitable gene markers expressing spoilage, we could put them into use as indicators illustrating and predicting changes in the quality of food products.