Lactiplantibacillus plantarum as a model species for VOCs studies in the food sector: VOCs monitoring in a microbiological medium using PTR-ToF-MS

• Autor(a) principal: Teixeira, Camila Cossettin
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/160597
• topic: Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias

This thesis combines a critical review part of the relevant scientific literature and an experi-mental part, both functional to highlight the interest in mass spectrometry techniques for monitoring and promoting innovation in the fermented products sector. The fermentation of food products brings to-gether complex bioprocesses with a relevant role in the green transition of food systems. Among these processes, lactic acid fermentation carried out by lactic acid bacteria (LAB) represents a transformation of great interest due to its potential impact on quality, safety, and human well-being. Volatile organic compounds (VOCs) represent an interesting and versatile class of chemical markers for monitoring and studying fermentations, as they are metabolites derived from microbial action and offer information on product quality. Direct-injection mass spectrometry (DIMS) techniques allow studies with excellent an-alytical performances, particularly interesting in evaluating fermentation processes. Proton Transfer Re-action - Time of Flight - Mass Spectrometer (PTR-ToF-MS) belongs to DIMS approaches and has var-ious applications in the field of fermentation. The critical review of the literature addressed the issue of analytical methodologies (innovative methodologies) and highlighted the importance of Lactiplanti-bacillus plantarum as a model species among lactic acid bacteria due to the versatility of applications in the field of fermentations of food interest, with an impact on different aspects of the quality of finished products. The overview of the scientific literature was combined with an experimental part on a prelim-inary evaluation of the PTR-ToF-MS in monitoring VOCs associated with the growth of L. plantarum. Six L. plantarum strains were grown separately in a culture medium and the volatiolome has been mon-itored throughout the growth curve. The results provided interesting preliminary evidence on the poten-tial of PTR-ToF-MS for the monitoring of LAB food fermentation, using L. plantarum as a model spe-cies.