Simultaneous enzymatic hydrolysis and lactic fermentation to obtain a yogurt with low lactose content

In a single-stage process with the simultaneous addition of β -galactosidase and lactic culture, the lactose conversion, the processing time, viscosity and syneresis were evaluated. Fermentation was promoted by lactic culture containing two probiotic microorganisms, Bifidobacterium animalis and Lact...

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Detalhes bibliográficos
Autores: Martins, André Rosa, Monteiro, Ricardo Lemos, Burkert, Janaina Fernandes de Medeiros, Burkert, Carlos André Veiga
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Brasil
Recursos:Universidade Federal do Rio Grande (FURG)
Repositorio:Repositório Institucional da FURG (RI FURG)
Idioma:inglés
OAI Identifier:oai:repositorio.furg.br:1/3944
Acesso em linha:http://repositorio.furg.br/handle/1/3944
Access Level:acceso abierto
Palavra-chave:Enzymatic catalysis
Lactose hydrolysis
Yogurt physical properties
β -galactosidase
Descrição
Resumo:In a single-stage process with the simultaneous addition of β -galactosidase and lactic culture, the lactose conversion, the processing time, viscosity and syneresis were evaluated. Fermentation was promoted by lactic culture containing two probiotic microorganisms, Bifidobacterium animalis and Lactobacillus acidophilus, associated with the typical microorganisms of yogurt. An enzymatic preparation containing β -galactosidases from Kluyveromyces lactis and Aspergillus niger was used. A central composite design (23 trials plus three central points) was proposed in order to evaluate the effects of initial lactose concentration, enzyme concentration and the time of addition of the enzyme. The following conditions were established: initial lactose concentration of 91 g L-1, enzyme concentration of 0.5 g L-1 and enzyme addition at the beginning of fermentation. In these conditions, a decrease in processing time (from 4.55 to 3.68 h) and an increase in lactose conversion (from 15.2 to 97.9%) were observed in relation to the fermentation without enzyme addition, and no detrimental changes in some physical properties of yogurt (viscosity, and syneresis).