Joining environmental impacts and product quality in Life Cycle Assessment: The case of the production and storage of lactic acid bacteria concentrates

Lactic acid bacteria are widely used in the food and pharmaceutical industries to produce fermented foods and probiotics. This study assesses the environmental impacts of fifteen production and storage strategies for lactic acid bacteria concentrates from two strains. A life cycle assessment was performed using pilot-scale data. Environmental impacts per functional unit were weighted based on biological activity using two approaches: one by final biological activity after storage and the other by activity at each production stage. Fermentation emerged as a key phase in both methods, with higher yields significantly reducing environmental impacts. Stabilization and storage also contributed substantially to both environmental impact and loss of biological activity. The choice of stabilization method and storage conditions depends on the strain and expected storage duration. The weighting method affected the results: weighting by final biological quality highlighted the preservation of activity while weighting by each production stage better reflected the material and energy flows responsible for environmental damage. This study identifies crucial stages for improving the sustainability of lactic acid bacteria production and suggests that integrating environmental and quality factors is essential when designing production processes.