Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation
Autor(a) principal: | |
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Data de Publicação: | 1995 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.14/6567 |
Resumo: | The concentration and temperature dependence of the gelation kinetics of high-methoxyl pectin (HMP; 60% sucrose, pH 3) was investigated using measurements of small-amplitude oscillatory shear. The rate of gelation close to the gel point can be described as a second-order rate process using the kinetic model of Ross-Murphy (Carbohydr. Polym. 1991, 14, 281) and a critical exponent close to that predicted by the percolation approach. The modulus after a long ageing time showed a power concentration dependence with an exponent around 3.1, higher than the classical square of concentration dependence, which was probably either due to the non-equilibrium state of the HMP gels even after long ageing times, or due to the proximity of the concentration range studied to the critical gelling concentration. The gelation rate of HMP/sucrose systems is strongly dependent on the temperature. An Arrhenius relationship was applied to describe this dependence. Two different processes are proposed to explain the discontinuity observed, each one having rates with different temperature dependence. The applicable kinetics at longer times are quite different, with a lower dependence on polymer concentration and ageing temperature. A non-isothermal kinetic model was used to describe the gelation process of the HMP/sucrose system during cooling. |
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Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelationHigh-methoxyl pectinsGelation kineticsGelation timeThe concentration and temperature dependence of the gelation kinetics of high-methoxyl pectin (HMP; 60% sucrose, pH 3) was investigated using measurements of small-amplitude oscillatory shear. The rate of gelation close to the gel point can be described as a second-order rate process using the kinetic model of Ross-Murphy (Carbohydr. Polym. 1991, 14, 281) and a critical exponent close to that predicted by the percolation approach. The modulus after a long ageing time showed a power concentration dependence with an exponent around 3.1, higher than the classical square of concentration dependence, which was probably either due to the non-equilibrium state of the HMP gels even after long ageing times, or due to the proximity of the concentration range studied to the critical gelling concentration. The gelation rate of HMP/sucrose systems is strongly dependent on the temperature. An Arrhenius relationship was applied to describe this dependence. Two different processes are proposed to explain the discontinuity observed, each one having rates with different temperature dependence. The applicable kinetics at longer times are quite different, with a lower dependence on polymer concentration and ageing temperature. A non-isothermal kinetic model was used to describe the gelation process of the HMP/sucrose system during cooling.ElsevierVeritati - Repositório Institucional da Universidade Católica PortuguesaSilva, J. A. Lopes daGonçalves, M. P.Rao, M. A.2011-10-20T18:37:38Z19951995-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.14/6567engSILVA, J. A. Lopes da; GONÇALVES, M. P.; RAO, M. A. - Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation. International Journal of Biological Macromolecules. ISSN 0141-813. Vol. 17 n.º 1 (1995), p. 25-3210.1016/0141-8130(95)93514-X7772559A1995QM43100005info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-07-12T17:11:07Zoai:repositorio.ucp.pt:10400.14/6567Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T18:06:11.432178Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
title |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
spellingShingle |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation Silva, J. A. Lopes da High-methoxyl pectins Gelation kinetics Gelation time |
title_short |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
title_full |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
title_fullStr |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
title_full_unstemmed |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
title_sort |
Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation |
author |
Silva, J. A. Lopes da |
author_facet |
Silva, J. A. Lopes da Gonçalves, M. P. Rao, M. A. |
author_role |
author |
author2 |
Gonçalves, M. P. Rao, M. A. |
author2_role |
author author |
dc.contributor.none.fl_str_mv |
Veritati - Repositório Institucional da Universidade Católica Portuguesa |
dc.contributor.author.fl_str_mv |
Silva, J. A. Lopes da Gonçalves, M. P. Rao, M. A. |
dc.subject.por.fl_str_mv |
High-methoxyl pectins Gelation kinetics Gelation time |
topic |
High-methoxyl pectins Gelation kinetics Gelation time |
description |
The concentration and temperature dependence of the gelation kinetics of high-methoxyl pectin (HMP; 60% sucrose, pH 3) was investigated using measurements of small-amplitude oscillatory shear. The rate of gelation close to the gel point can be described as a second-order rate process using the kinetic model of Ross-Murphy (Carbohydr. Polym. 1991, 14, 281) and a critical exponent close to that predicted by the percolation approach. The modulus after a long ageing time showed a power concentration dependence with an exponent around 3.1, higher than the classical square of concentration dependence, which was probably either due to the non-equilibrium state of the HMP gels even after long ageing times, or due to the proximity of the concentration range studied to the critical gelling concentration. The gelation rate of HMP/sucrose systems is strongly dependent on the temperature. An Arrhenius relationship was applied to describe this dependence. Two different processes are proposed to explain the discontinuity observed, each one having rates with different temperature dependence. The applicable kinetics at longer times are quite different, with a lower dependence on polymer concentration and ageing temperature. A non-isothermal kinetic model was used to describe the gelation process of the HMP/sucrose system during cooling. |
publishDate |
1995 |
dc.date.none.fl_str_mv |
1995 1995-01-01T00:00:00Z 2011-10-20T18:37:38Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10400.14/6567 |
url |
http://hdl.handle.net/10400.14/6567 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
SILVA, J. A. Lopes da; GONÇALVES, M. P.; RAO, M. A. - Kinetics and thermal behaviour of the structure formation process in HMP/sucrose gelation. International Journal of Biological Macromolecules. ISSN 0141-813. Vol. 17 n.º 1 (1995), p. 25-32 10.1016/0141-8130(95)93514-X 7772559 A1995QM43100005 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799131728315416577 |