Effects of pH and sugar concentration in Zygosaccharomyces rouxii growth and time for spoilage in concentrated grape juice at isothermal and non-isothermal conditions

The effect of pH (1.7-3.2) and sugar concentration (64-68 °Brix) on the growth of Zygosaccharomyces rouxii MC9 using response surface methodology was studied. Experiments were carried out in concentrated grape juice inoculated with Z.rouxii at isothermal conditions (23°C) for 60 days. pH was the var...

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Detalles Bibliográficos
Autores: Rojo, María Cecilia, Arroyo López, Francisco Noé, Lerena, M.C., Mercado, Laura A., Torres, Álvaro, Combina, Mariana
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/115818
Acceso en línea:http://hdl.handle.net/10261/115818
Access Level:acceso abierto
Palabra clave:Response surface methodology
pH
Sugar concentration
Zygosaccharomyces rouxii
Spoilage
Concentrated grape juice
Descripción
Sumario:The effect of pH (1.7-3.2) and sugar concentration (64-68 °Brix) on the growth of Zygosaccharomyces rouxii MC9 using response surface methodology was studied. Experiments were carried out in concentrated grape juice inoculated with Z.rouxii at isothermal conditions (23°C) for 60 days. pH was the variable with the highest effect on growth parameters (potential maximum growth rate and lag phase duration), although the effect of sugar concentration were also significant. In a second experiment, the time for spoilage by this microorganism in concentrated grape juice was evaluated at isothermal (23°C) and non-isothermal conditions, in an effort to reproduce standard storage and overseas shipping temperature conditions, respectively. Results show that pH was again the environmental factor with the highest impact on delaying the spoilage of the product. Thereby, a pH value below 2.0 was enough to increase the shelf life of the product for more than 60 days in both isothermal and non-isothermal conditions. The information obtained in the present work could be used by producers and buyers to predict the growth and time for spoilage of Z.rouxii in concentrated grape juice. © 2013 Elsevier Ltd.