Effect of homogenisation on protein distribution and proteolysis during storage of indirectly heated UHT milk

[EN] This paper compares modifications in whey proteins and caseins and proteolysis during storage (120 days) at 20 °C of unhomogenised and homogenised milks (2% fat) heated (137 °C, 4 s) in a pilot-scale indirect UHT plant. Homogenisation resulted in the attachment of caseins and whey proteins to t...

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Detalhes bibliográficos
Autores: García-Risco, Mónica R., Villamiel, Mar, López-Fandiño, Rosina
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/397954
Acesso em linha:http://hdl.handle.net/10261/397954
Access Level:acceso abierto
Palavra-chave:Homogenisation
UHT milk
Distribution des protéines
Protéolyse
Descrição
Resumo:[EN] This paper compares modifications in whey proteins and caseins and proteolysis during storage (120 days) at 20 °C of unhomogenised and homogenised milks (2% fat) heated (137 °C, 4 s) in a pilot-scale indirect UHT plant. Homogenisation resulted in the attachment of caseins and whey proteins to the milk fat globule membrane, changed the morphology of casein micelles and gave rise to small micellar particles, not easily sedimentable by centrifugation. It also promoted whey protein denaturation and slowed down enzymatic reactions that depend on residual proteinase, glycosidase and phosphatase activities. Homogenisation of milk before UHT treatment led to lower levels of the enzymes that contribute to deterioration during storage. This phenomenon, together with an increased complex formation between κ-casein and β-lactoglobulin, could be responsible for reduced proteolytic degradation.