Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix
The ability of galacto-oligosaccharides (GOS) to protect Lactobacillus delbrueckii subsp. bulgaricus upon freeze drying was analyzed on the basis of their capacity to form glassy structures. Glass transition temperatures (T g) of a GOS matrix at various relative humidities (RH) were determined by DS...
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Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01681605_v155_n3_p217_Tymczyszyn http://hdl.handle.net/20.500.12110/paper_01681605_v155_n3_p217_Tymczyszyn |
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paper:paper_01681605_v155_n3_p217_Tymczyszyn2023-06-08T15:17:19Z Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix Sosa, Natalia Schebor, Carolina C. Freeze drying Galacto-oligosaccharides Lactobacillus Membrane damage Molecular mobility Water activity cryoprotective agent galactose oligosaccharide article bacterial survival bacterial viability bacterium controlled study cryoprotection freeze drying freezing glass transition temperature humidity lactobacillus bulgaricus nonhuman proton nuclear magnetic resonance storage storage temperature water content Cell Membrane Colony Count, Microbial Cryoprotective Agents Freeze Drying Humidity Lactobacillus Microbial Viability Oligosaccharides Probiotics Transition Temperature Water Lactobacillus Lactobacillus delbrueckii subsp. bulgaricus The ability of galacto-oligosaccharides (GOS) to protect Lactobacillus delbrueckii subsp. bulgaricus upon freeze drying was analyzed on the basis of their capacity to form glassy structures. Glass transition temperatures (T g) of a GOS matrix at various relative humidities (RH) were determined by DSC. Survival of L. bulgaricus in a glassy GOS matrix was investigated after freezing, freeze drying, equilibration at different RHs and storage at different temperatures. At 32°C, a drastic viability loss was observed. At 20°C, the survival was affected by the water content, having the samples stored at lower RHs, the highest survival percentages. At 4°C, no decay in the cells count was observed after 45days of storage. The correlation between molecular mobility [as measured by Proton nuclear magnetic resonance ( 1H NMR)] and loss of viability explained the efficiency of GOS as cryoprotectants. The preservation of microorganisms was improved at low molecular mobility and this condition was obtained at low water contents and low storage temperatures. These results are important in the developing of new functional foods containing pre and probiotics. © 2012 Elsevier B.V. Fil:Sosa, N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Schebor, C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2012 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01681605_v155_n3_p217_Tymczyszyn http://hdl.handle.net/20.500.12110/paper_01681605_v155_n3_p217_Tymczyszyn |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
Freeze drying Galacto-oligosaccharides Lactobacillus Membrane damage Molecular mobility Water activity cryoprotective agent galactose oligosaccharide article bacterial survival bacterial viability bacterium controlled study cryoprotection freeze drying freezing glass transition temperature humidity lactobacillus bulgaricus nonhuman proton nuclear magnetic resonance storage storage temperature water content Cell Membrane Colony Count, Microbial Cryoprotective Agents Freeze Drying Humidity Lactobacillus Microbial Viability Oligosaccharides Probiotics Transition Temperature Water Lactobacillus Lactobacillus delbrueckii subsp. bulgaricus |
spellingShingle |
Freeze drying Galacto-oligosaccharides Lactobacillus Membrane damage Molecular mobility Water activity cryoprotective agent galactose oligosaccharide article bacterial survival bacterial viability bacterium controlled study cryoprotection freeze drying freezing glass transition temperature humidity lactobacillus bulgaricus nonhuman proton nuclear magnetic resonance storage storage temperature water content Cell Membrane Colony Count, Microbial Cryoprotective Agents Freeze Drying Humidity Lactobacillus Microbial Viability Oligosaccharides Probiotics Transition Temperature Water Lactobacillus Lactobacillus delbrueckii subsp. bulgaricus Sosa, Natalia Schebor, Carolina C. Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
topic_facet |
Freeze drying Galacto-oligosaccharides Lactobacillus Membrane damage Molecular mobility Water activity cryoprotective agent galactose oligosaccharide article bacterial survival bacterial viability bacterium controlled study cryoprotection freeze drying freezing glass transition temperature humidity lactobacillus bulgaricus nonhuman proton nuclear magnetic resonance storage storage temperature water content Cell Membrane Colony Count, Microbial Cryoprotective Agents Freeze Drying Humidity Lactobacillus Microbial Viability Oligosaccharides Probiotics Transition Temperature Water Lactobacillus Lactobacillus delbrueckii subsp. bulgaricus |
description |
The ability of galacto-oligosaccharides (GOS) to protect Lactobacillus delbrueckii subsp. bulgaricus upon freeze drying was analyzed on the basis of their capacity to form glassy structures. Glass transition temperatures (T g) of a GOS matrix at various relative humidities (RH) were determined by DSC. Survival of L. bulgaricus in a glassy GOS matrix was investigated after freezing, freeze drying, equilibration at different RHs and storage at different temperatures. At 32°C, a drastic viability loss was observed. At 20°C, the survival was affected by the water content, having the samples stored at lower RHs, the highest survival percentages. At 4°C, no decay in the cells count was observed after 45days of storage. The correlation between molecular mobility [as measured by Proton nuclear magnetic resonance ( 1H NMR)] and loss of viability explained the efficiency of GOS as cryoprotectants. The preservation of microorganisms was improved at low molecular mobility and this condition was obtained at low water contents and low storage temperatures. These results are important in the developing of new functional foods containing pre and probiotics. © 2012 Elsevier B.V. |
author |
Sosa, Natalia Schebor, Carolina C. |
author_facet |
Sosa, Natalia Schebor, Carolina C. |
author_sort |
Sosa, Natalia |
title |
Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
title_short |
Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
title_full |
Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
title_fullStr |
Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
title_full_unstemmed |
Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
title_sort |
effect of physical properties on the stability of lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix |
publishDate |
2012 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01681605_v155_n3_p217_Tymczyszyn http://hdl.handle.net/20.500.12110/paper_01681605_v155_n3_p217_Tymczyszyn |
work_keys_str_mv |
AT sosanatalia effectofphysicalpropertiesonthestabilityoflactobacillusbulgaricusinafreezedriedgalactooligosaccharidesmatrix AT scheborcarolinac effectofphysicalpropertiesonthestabilityoflactobacillusbulgaricusinafreezedriedgalactooligosaccharidesmatrix |
_version_ |
1768542264899928064 |