Anti-Casein polyclonal antibody

Mozzarella cheese is traditionally prepared from bubaline (Bubalus bubalis) milk, but product adulteration occurs mainly by addition of or full substitution by bovine milk. The aim of this study was to show the usefulnes of molecular markers to identify the admixture of bovine milk to bubaline milk during the manufacturing process of mozzarella cheese. Samples of mozzarella cheese were produced by adding seven different concentrations of bovine milk: 0%, 1%, 2%, 5%, 8%, 12% and 100%. DNA extracted from somatic cells found in cheese were submitted to PCR-RFLP analysis of casein genes: alpha-s1-CN - CSN1S1 that encompasses 954 bp from exon VII to intron IX (Alu I and Hinf I), alpha-CN - CSN2 including 495 bp of exon VII (Hae III and Hinf I), and kappa-CN - CSN3, encompassing 373 bp of exon IV (Alu I and Hind III). Our results indicate that Hae III-RFLP of CSN2 exon VII can be used as a molecular marker to detect the presence of bovine milk in "mozzarella" cheese.

The aim of the study was to investigate the effect of composite CSN1S1-CSN3 [alpha(S1)-kappa-casein (CN)] genotype on milk protein composition in Mediterranean water buffalo. Content of alpha(S1)-CN, alpha(S2)-CN, beta-CN, gamma-CN, kappa-CN, glycosylated and unglycosylated kappa-CN, alpha-lactalbumin, and beta-lactoglobulin was measured by reversed-phase HPLC using 621 individual milk samples. Genotypes at CSN1S1 and CSN3 were also obtained by reversed-phase HPLC. Two alleles were detected at CSN1S1 (corresponding to the A and B variants, 062823: p.Leu193Ser,) and at CSN3 (corresponding to the X1 and X2 variants, CAP12622.1: p.Ile156Thr). Increased proportions of alpha(S1)-CN in total casein (TCN) were associated with genotypes carrying CSN1S1 A. Genotypes associated with a marked decrease of the proportion of alpha(S1)-CN in TCN (composite genotypes AB-X1X1 and BB-X1X2) were associated with marked increases in the proportion of alpha(S2)-CN. In addition, composite genotypes carrying the X1 allele at CSN3 were associated with a greater proportion of alpha(S2)-CN in TCN relative to those carrying CSN3 X2. Composite genotypes greatly affected also the variability of ratios of kappa-CN to TCN, with genotypes carrying the X1 allele at CSN3 being associated with decreased ratios. The decreased content of glycosylated kappa-CN associated with CSN3 X1 was responsible for the overall lower content of total kappa-CN in milk of X1-carrying animals. Increasing the frequency of specific genotypes might be an effective way to alter milk protein composition, namely the proportion of alpha(S1)-CN, alpha(S2)-CN, and kappa-CN in TCN, and the degree of glycosylation of kappa-CN.