Freeze-Drying Injury of Lactobacillus Acidophilus

Abstract

Lactobacillus acidophilus ATCC 4355 cells were more stable to freezing at −20°C after supplementation of the growth medium with 0.1% CaCO3. However, added calcium did not affect viability and injury during lyophilization. Inclusion of 5% glycerol in the suspending medium before freeze-drying resulted in superior survival and decreased injury during the drying process.

Accelerated storage testing of freeze-dried and controlled low-temperature vacuum dehydrated Lactobacillus acidophilus.

“…Culture dehydration of L. acidophilus was normally performed by freeze-drying which might cause damage to cells owing to the freezing and subsequent drying treatment (Bozoglu and Gurakan, 1989;Champagne et al, 1991;Marth, 1973). The culture might be mixed with some protectants in order to improve survival during the drying process (Potts, 1994).…”

“…The cell pellets were then suspended in 10 ml protective media to make concentrated cell suspensions of about 10 9 -10 10 cells/ml for the experiments. Three different protective media were used for experiments: (1) 10% NFDMS was used as the basal medium for drying without protectants (Bozoglu and Gurakan, 1989;King and Su, 1993), (2) 4.15% glycerol and 10.08% NFDMS for freeze-drying, and (3) 4.10% glycerol and 10.71% NFDMS for CLTVD with protectants based on the optimum conditions obtained by King and Lin (1995).…”

Comparative Studies on the Activity of Freeze-Dried Mesophilic Lactic Acid Cultures for Direct Application

“…Comparative studies have shown preserved acidification capacity for 2-16 hours when applied directly, though with a certain delay in the first hours. Other authors also mention relatively weak changes in the acidification capacity of frozen or freeze-dried concentrates of lactic acid bacteria (2,5,7,8).…”

Biotechnological Developments in Turkey

“…Inclusion of 5% glycerol also provided a survival of 98% and was better than a combination of 0.5% NH,CI + 10% sucrose + 0.5% ascorbate. On the other hand, the injured fraction drastically increased after freeze drying in all conditions, except for glycerol supplementation, which could ensure a survival ratio of 57% (Bozogu and Gurakan, 1989).…”