Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes
The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dairy systems and its relationship with simultaneous chemical (i.e. non-enzymatic browning, NEB) and physical changes (structural collapse) at temperatures from 70 to 105°C. The presence of milk proteins ha...
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2002
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_03088146_v76_n4_p423_Burin http://hdl.handle.net/20.500.12110/paper_03088146_v76_n4_p423_Burin |
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paper:paper_03088146_v76_n4_p423_Burin2023-06-08T15:31:47Z Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes Burín, Leila Buera, María del Pilar Hough, Guillermo β-galactosidase Dehydrated dairy products Enzyme stability Glass transition Non enzymatic browning: Collapse beta galactosidase lactose milk protein article dairy product dehydration enzyme activity enzyme inactivation enzyme stability heat tolerance physical chemistry storage temperature temperature The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dairy systems and its relationship with simultaneous chemical (i.e. non-enzymatic browning, NEB) and physical changes (structural collapse) at temperatures from 70 to 105°C. The presence of milk proteins had a structure-stabilizing effect, which was not reflected by enzymic stabilization or NEB prevention. Although the remaining enzyme activity was correlated with physical and chemical changes in some of the systems exposed at 22% R.H., these changes were not parallel to the macroscopic changes in some of the anhydrous systems. The single lactose systems were highly collapsed at all the temperatures analyzed, but enzymic inactivation and NEB were dependent on the storage temperature rather than on the degree of collapse. Chemical and physical changes were not correlated to the remaining activity. Changes which occur at a molecular level may not be related to the changes at a supramolecular level (such as those derived from glass transition or collapse). © 2002 Elsevier Science Ltd. All rights reserved. Fil:Burin, L. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Buera, M.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Hough, G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2002 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_03088146_v76_n4_p423_Burin http://hdl.handle.net/20.500.12110/paper_03088146_v76_n4_p423_Burin |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
β-galactosidase Dehydrated dairy products Enzyme stability Glass transition Non enzymatic browning: Collapse beta galactosidase lactose milk protein article dairy product dehydration enzyme activity enzyme inactivation enzyme stability heat tolerance physical chemistry storage temperature temperature |
| spellingShingle |
β-galactosidase Dehydrated dairy products Enzyme stability Glass transition Non enzymatic browning: Collapse beta galactosidase lactose milk protein article dairy product dehydration enzyme activity enzyme inactivation enzyme stability heat tolerance physical chemistry storage temperature temperature Burín, Leila Buera, María del Pilar Hough, Guillermo Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| topic_facet |
β-galactosidase Dehydrated dairy products Enzyme stability Glass transition Non enzymatic browning: Collapse beta galactosidase lactose milk protein article dairy product dehydration enzyme activity enzyme inactivation enzyme stability heat tolerance physical chemistry storage temperature temperature |
| description |
The objective was to study the remaining activity of the enzyme β-galactosidase in dehydrated dairy systems and its relationship with simultaneous chemical (i.e. non-enzymatic browning, NEB) and physical changes (structural collapse) at temperatures from 70 to 105°C. The presence of milk proteins had a structure-stabilizing effect, which was not reflected by enzymic stabilization or NEB prevention. Although the remaining enzyme activity was correlated with physical and chemical changes in some of the systems exposed at 22% R.H., these changes were not parallel to the macroscopic changes in some of the anhydrous systems. The single lactose systems were highly collapsed at all the temperatures analyzed, but enzymic inactivation and NEB were dependent on the storage temperature rather than on the degree of collapse. Chemical and physical changes were not correlated to the remaining activity. Changes which occur at a molecular level may not be related to the changes at a supramolecular level (such as those derived from glass transition or collapse). © 2002 Elsevier Science Ltd. All rights reserved. |
| author |
Burín, Leila Buera, María del Pilar Hough, Guillermo |
| author_facet |
Burín, Leila Buera, María del Pilar Hough, Guillermo |
| author_sort |
Burín, Leila |
| title |
Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| title_short |
Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| title_full |
Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| title_fullStr |
Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| title_full_unstemmed |
Thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| title_sort |
thermal resistance of β-galactosidase in dehydrated dairy model systems as affected by physical and chemical changes |
| publishDate |
2002 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_03088146_v76_n4_p423_Burin http://hdl.handle.net/20.500.12110/paper_03088146_v76_n4_p423_Burin |
| work_keys_str_mv |
AT burinleila thermalresistanceofbgalactosidaseindehydrateddairymodelsystemsasaffectedbyphysicalandchemicalchanges AT bueramariadelpilar thermalresistanceofbgalactosidaseindehydrateddairymodelsystemsasaffectedbyphysicalandchemicalchanges AT houghguillermo thermalresistanceofbgalactosidaseindehydrateddairymodelsystemsasaffectedbyphysicalandchemicalchanges |
| _version_ |
1768544596248231936 |