Exploiting agri-food residues for kombucha tea and bacterial cellulose production

• Published in: International journal of biological macromolecules 2025-01, p.140293, Article 140293
• Main Authors: Sabatini, Francesca, Maresca, Emanuela, Aulitto, Martina, Termopoli, Veronica, De Risi, Arianna, Correggia, Monica, Fiorentino, Gabriella, Consonni, Viviana, Gosetti, Fabio, Orlandi, Marco, Lange, Heiko, Contursi, Patrizia
• Format: Article
• Language: English
• Subjects: Agri-food wastes; Antioxidant activity; Bacterial cellulose; Chemometrics; GC–MS; Kombucha
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2025.140293

Bio-valorization of agri-food wastes lies in their possible conversion into fermented foodstuffs/beverages and/or biodegradable polymers such as bacterial cellulose. In this study, three different kombucha cultures were formulated using agri-food waste materials, citrus fruit residues and used coffee grounds, as alternative carbon and nitrogen sources, respectively. Over 21 days of fermentation, the kinetic profile was followed by monitoring cell number, pH variation, minerals, trace elements and production of bacterial cellulose. Moreover, the total phenolic and radical scavenging capacity was measured by spectrophotometric tests on the beverage and bacterial cellulose. Several classes of compounds were detected by gas chromatography coupled with mass spectrometry performing extractions on the headspace above fresh kombucha beverages and their lyophilized fractions, using head space solid phase micro extraction and liquid phase extraction, respectively. The obtained results allowed assessing molecular profiles of each kombucha beverages. A chemometric meta-analysis of the data revealed the individual impacts of the single ingredients and the effects of the fermentation process. [Display omitted]