Skip to main content
Ir a la página de inicio de la Comisión Europea (se abrirá en una nueva ventana)
español español
CORDIS - Resultados de investigaciones de la UE
CORDIS
Contenido archivado el 2024-04-30

Lactic acid bacteria with modified proteolytic properties in milk fermentation

Objetivo



Fermentation of milk by lactic acid bacteria is essential for the production of cheese, yoghurt and other dairy products. The degradation of milk proteins during milk fermentations is catalysed by many different enzymes which together form the proteolytic system. The activity of this proteolytic system determines the rate and extent of the fermentation process and plays a crucial role in the development of the rheological and organoleptic properties of the final product. The components of the proteolytic systems of Lactococcus lactis, Lactobacilllus helveticus and Lactobacillus delbrückii have been studied in detail both at the biochemical and the genetic level. In this project various complementary approaches will be used to genetically modify the proteolytic properties of L.lactis. Strains will be constructed in which (i) the activity, specificity and/or stability of the proteinases PrtP has been engineered; (ii) the peptide transport activity and specificity has been engineered; (iii) the activity of one or multiple peptidases has been affected either by gene deletion or overexpression; the genes encoding 8 unique peptidases of L.lactis and at least 5 other unique enzymes from the lactobacillus species are available for these studies; (iv) combinations of these enzymes are affected. Food-grade cloning techniques, based on self-cloning, will be used to genetically engineer L.lactis which will allow the evaluation of the modified strains in cheese trials. The breakdown of caseins by these modified strains will be followed in detail by on-line HPLC-ion mass spray spectrometry measurements, which will reveal bottlenecks in the proteolytic pathway and identify the relative importance of specific peptides as nitrogen sources for the organism and/or sources of flavour compounds.
Finally, the complex (coordinated) regulation of expression of the components of the proteolytic pathway will be studied by fusing expression signals to genes encoding specific reporter proteins, and by analysing proteolysis in the cheese matrix directly with specific enzyme assays. Following the construction of the first generation of modified L.lactis strains, and their biochemical characterization, cheese slurry experiments and small scale cheese trials will be carried out with single and mixed starter cultures. The proteolysis in the cheeses will be evaluated by official cheese examiners. Based on the outcome of these studies new (second generation) strains will be constructed and selected strains (with desirable properties) will be tested further in large scale cheese trials.

Ámbito científico (EuroSciVoc)

CORDIS clasifica los proyectos con EuroSciVoc, una taxonomía plurilingüe de ámbitos científicos, mediante un proceso semiautomático basado en técnicas de procesamiento del lenguaje natural. Véas: El vocabulario científico europeo..

Para utilizar esta función, debe iniciar sesión o registrarse

Programa(s)

Programas de financiación plurianuales que definen las prioridades de la UE en materia de investigación e innovación.

Tema(s)

Las convocatorias de propuestas se dividen en temas. Un tema define una materia o área específica para la que los solicitantes pueden presentar propuestas. La descripción de un tema comprende su alcance específico y la repercusión prevista del proyecto financiado.

Convocatoria de propuestas

Procedimiento para invitar a los solicitantes a presentar propuestas de proyectos con el objetivo de obtener financiación de la UE.

Datos no disponibles

Régimen de financiación

Régimen de financiación (o «Tipo de acción») dentro de un programa con características comunes. Especifica: el alcance de lo que se financia; el porcentaje de reembolso; los criterios específicos de evaluación para optar a la financiación; y el uso de formas simplificadas de costes como los importes a tanto alzado.

CSC - Cost-sharing contracts

Coordinador

UNIVERSITY OF GRONINGEN
Aportación de la UE
Sin datos
Dirección
30,Kerklaan 30
9751 NN HAREN GN
Países Bajos

Ver en el mapa

Coste total

Los costes totales en que ha incurrido esta organización para participar en el proyecto, incluidos los costes directos e indirectos. Este importe es un subconjunto del presupuesto total del proyecto.

Sin datos

Participantes (9)

Mi folleto 0 0