Encapsulation of probiotic bacteria into amorphous matrices has been shown to maintain their viability during storage. The objective of the present study was to find out if the Lactobacillus fermentum ME-3 cells could be protected by sugars (maltose, lactose and trehalose) and sugar alcohols (lactitol and maltitol) during freeze-drying and storage. Probiotic cells were freeze-dried with each compound and stored at 25 °C at relative humidities (RH) of 0, 11, 33 and 54%. Water sorption and glass transition temperatures (Tg) of samples were determined for calculation of critical RH (RH lowering the Tg to 25 °C) being 33-36% for sugars, 17% for lactitol and 8% for maltitol. All sugars and sugar alcohols were found to protect cells during freeze-drying. During storage the viability of cells remained best at RH of 11%. Viability of the cells at RH of 54% decreased most due to crystallization of trehalose, lactose and lactitol. Instead, crystallization of maltose and maltitol was not observed and the viability of the cells was maintained partly. L. fermentum ME-3 cells could be protected by sugars and sugar alcohols during freeze-drying and storage at RH below their critical RH. However, sugar alcohols protected cells also at RH above their critical RH.
|Otsikko||12th European symposium on comminution and classification (ESCC 2009) : 15-18 September 2009, Dipoli Congress Center, Espoo, Finland|
|Kustantaja||European Space Components Coordination, ESCC|
|Tila||Julkaistu - 2009|
|OKM-julkaisutyyppi||A4 Artikkeli konferenssijulkaisuussa|
|Tapahtuma||12th European Symposium on Comminution and Classification (ESCC 2009) - Espoo, Suomi|
Kesto: 15 syyskuuta 2009 → 18 syyskuuta 2009