Influence of somatic cell count and breed on capillary electrophoretic protein profiles of ewes' milk: a chemometric study.
Bulk tank ewe milk from the Assaf, Castellana, and Churra breeds categorized into 3 somatic cell count (SCC) groups (<500,000; 1,000,000 to 1,500,000; and >2,500,000 cells/mL) was used to investigate changes in chemical composition and capillary electrophoresis protein profiles. The results obtained indicated that breed affected fat, protein, and total solids levels, and differences were also observed for the following milk proteins: beta-, beta1-, beta2-, and alpha(s1)-III-casein, alpha-lactalbumin, and beta-lactoglobulin. High SCC affected fat and protein contents and bacterial counts. The level of beta1-, beta2-, and alpha(s1)-I-casein, and alpha-lactalbumin were significantly lower in milk with SCC scores >2,500,000 cells/mL. A preliminary study of the chemical, microbiological, and electrophoretic data was performed by cluster analysis and principal components analysis. Applying discriminant analysis, it was possible to group the milk samples according to breed and level of SCC, obtaining a prediction of 100 and 97% of the samples, respectively.
Rodríguez-Nogales
J M
JM
Food Technology Area, University of Valladolid, E.T.S. de Ingenierías Agrarias, Avda. Madrid 57, 34004 Palencia, Spain.
Vivar-Quintana
A M
AM
Revilla
I
I
D000704:Analysis of Variance; D000818:Animals; D001947:Breeding; D002452:Cell Count / Q000662:veterinary; D016000:Cluster Analysis; D015169:Colony Count, Microbial / Q000662:veterinary; D004041:Dietary Fats / Q000032:analysis; D016002:Discriminant Analysis; D019075:Electrophoresis, Capillary / Q000379:methods / Q000662:veterinary*; D005504:Food Analysis / Q000379:methods; D008892:Milk / Q000737:chemistry* / Q000145:classification / Q000166:cytology* / Q000382:microbiology; D008894:Milk Proteins / Q000032:analysis*; D015999:Multivariate Analysis; D025341:Principal Component Analysis; D012756:Sheep / Q000502:physiology*; D013223:Statistics as Topic / Q000379:methods
D004041:Dietary Fats; D008894:Milk Proteins