Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Utilization of milk from different goat breeds

The project involves introducing innovative factors for the breeder (genetic selection of goats), for the processor (new technological parameters), and for the consumer (diversified cheeses) in relation to the utilization of milk from different goat breeds reared in marginal areas of the European Union. The task concerns screening goat breeds/populations from different agro-pastoral systems and environments in Italy, France and Greece and collecting their milk for analysis. From the 229 Italian goat milk samples analysed (aS1 casein locus) in the first year, five goat genotypes were identified while a sixth category embraced weak and null genotypes. The evaluation of milk quality based on total protein content may not be `consistent' as important cheese quality parameters may be related to the different protein fractions, their relative content in the milk, and also to their different physical and chemical characteristics. For this reason attention is being focused on methods of analysis for the casein fractions including optimization of the polyacrylamide gel isoelectric focusing technique which is giving good resolutions for aS1, aS2 and b-casein; high pressure reverse-phase liquid chromatography is also being used. Microfiltration technology is being applied to reduce bacterial populations in the milk, while the long-term storage properties of the goats milk after different thermal treatments is also being studied. Pasteurization (27% loss) and ultraheat treatment (UHT) (82% loss) resulted in the loss of whey proteins while low fat(1.8%) goats milk was more prone to storage problems (sediment and colour problems) than full fat.