| heal.abstract |
On the basis of an increasing demand for food quality, numerous methods have been developed for the detection of unlabeled presence of bovine milk in ovine milk products. Recently developed methods based on the amplification of DNA fragments originated from somatic cells are suitable for such analyses, since deoxyribonucleic acid molecules appear to be stable during milk processing or cheese ripening. The choice of this approach is further encouraged by the fact that DNA extraction from cheese and yogurt using silica spin columns is easy, quick and suitable for routine use. However, the small amounts of starting material recommended for this extraction procedure usually lead to low yields of amplified DNA. Aiming to overcome this difficulty, we describe here a PCR-RFLP method based on multicopy-numbered mitochondrial cytochrome b specific sequences, previously reported for meat identification. This approach enabled us to detect in a reliable species-specific restriction fragment pattern the presence of 1 and 2.5% bovine milk in ovine cheese (Feta) and yogurt respectively. |
en |