Effects of sheep alpha s1-casein CC, CD and DD genotypes on milk composition and cheesemaking properties.
The effects of sheep alpha s1-casein CC, CD and DD genotypes on milk composition and cheese yield were studied. Processed bulk milk was collected from three groups of 15 ewes, carrying alpha s1-casein CC, CD and DD genotypes. CC milk was higher in casein content than CD or DD milk (+3.5 and +8.6% respectively), and had a higher protein: fat ratio and a smaller casein micelle diameter. In addition, DD milk had a significantly lower alpha s1-casein content. The main differences were in curd formation: CC milk had better renneting properties. Cheesemaking trials, carried out in a pilot plant, showed that CC milk had better cheesemaking characteristics than DD milk, while CD milk was intermediate. Both 1 d old and fully ripened cheeses had different fat: dry matter ratios and alpha s1-I-casein electrophoretic mobilities: these were lower for DD cheese. As a consequence, these genotypes could be considered as markers of milk and/or cheese quality.
Pirisi
A
A
Istituto Zootecnico e Caseario per la Sardegna, Olmedo, Italia.
Piredda
G
G
Papoff
C M
CM
Di Salvo
R
R
Pintus
S
S
Garro
G
G
Ferranti
P
P
Chianese
L
L
D000818:Animals; D002364:Caseins / Q000737:chemistry / Q000235:genetics*; D002611:Cheese / Q000032:analysis; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005838:Genotype; D015151:Immunoblotting; D007525:Isoelectric Focusing; D013058:Mass Spectrometry; D008823:Micelles; D008892:Milk / Q000737:chemistry*; D010316:Particle Size; D012756:Sheep
D002364:Caseins; D008823:Micelles