Impact of media culture, freeze-drying and storage conditions on preservation of Lacticaseibacillus paracasei 90: viability and metabolic potential as a secondary culture in semi-hard cheese

PERALTA, GUILLERMO H.; BERET, M. VICTORIA; BURGI, M. D. MILAGROS; ALE, ELISA CARMEN; MARTÍNEZ, LUCIANO; ALBARRACÍN, VIRGINIA; WOLF, IRMA V.; BERGAMINI, CARINA

INTERNATIONAL DAIRY JOURNAL

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2023

0958-6946

Freeze-drying is the main process used to preserve lactic bacterial cultures at industrial level; however, their viability and metabolic activity could be affected not only by the process per se but also by the storage conditions. This study investigated the effect of freeze-drying and long-term storage (14 months) on the viability and metabolic activity of Lacticaseibacillus paracasei 90 (L90) grown in three culture media. The freeze-drying process did not influence its culturability and viability, regardless of the culture media used. The storage of the freeze-dried cultures at room temperature had a negative impact on viability, culturability and its ability to grow and acidify milk. On the contrary, L90 was able to withstand a long period of storage at low temperatures (14 months/4 ºC) and keep the desirable technological features of ripening culture. Overall, the results obtained demonstrate the robustness of this strain to be used as a secondary culture in the food industry.