Variazioni annuali dei principali caratteri qualitativi del latte ovino di massa in alcuni allevamenti dell' Emilia Romagna.
1993
Manfredini M. | Stipa S. | Nanni N. | Boattini B.
The analysis of 153 bulk ewe milk samples were performed. The samples were collected twice monthly troughout the year from 21 farms in Northern Italy. Samples were analysed for: density, titratable acidity, pH, total solid, fat, total proteins, whey proteins, caseins, ash, somatic cell count (SCC), standard plate count, coliforms and coagulating properties, i.e. rennet clotting time (r), rate of curd firming (k sub(20)) and curd firmess after 30 minutes (a sub(30)). Lower fat contents (min. 5.95%) were found in the first stage of lactation, while higher values (max. 7.69%) were found at the end of lactation. Protein content had a similar trend and ranged from 5.36% in January to 7.11% in September. Standard plate count varied from 858,000 to 8,369,000 c.f.u./ml. On a monthly average basis, SCC showed a high variability and range from 650,000 to about 3,000,000 per ml. As far as coagulation parameters are concerned, 79.08% of the samples had good coagulation properties (r less than 15 min. and k sub(20) less than 4 min.); 7.19% of the samples did not coagulate within 30 min, while 13.08% of the samples showed r values more than 15 min. Samples with abnormal coagulating properties had higher values of whey proteins, ash, pH and SCC.
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