New insights in goat breeds of Ethiopia: High content of alpha(s1)-CN and its association with coagulation properties, whey syneresis and micelle size

作者：Mestawet T A^*; Girma A; Adnoy T; Devold T G; Narvhus J A; Vegarud G E

来源：Small Ruminant Research, 2014, 119(1-3): 146-155.

DOI：10.1016/j.smallrumres.2014.02.011

• Individual casein content
• alpha(s1)-Casein genotype
• Micellar size
• Coagulation properties
• Whey syneresis
• Goat%26apos
• s milk

Milk from 94 Ethiopian goats (four breeds) was assessed for casein level, micellar size, coagulation properties and whey syneresis to evaluate cheese-making potential. Casein content (g/kg) ranged from 6.84 to 8.94 (alpha(s1)); 4.16-4.98 (alpha(s2)); 12.51-15.37 (beta) and 6.89-8.93 (kappa). Arsi-Bale goats had the highest alpha(s1)-casein (8.94 g/kg) followed by the Somali goats (7.90 g/kg); and were higher than Boer (7.05 g/kg) and Cross (6.84 g/kg) (P %26lt; 0.001). Milk from Arsi-Bale and Somali goats had significantly (P %26lt; 0.05) smaller micelles; 207.47 and 209.29 nm respectively than Boer (230.30 nm) and Cross (228.71 nm). Significantly stronger gels (P %26lt; 0.05) were obtained from milk samples with higher alpha(s1)-CN level and smaller micelles (Arsi-Bale 37.99 mm and Somali 36.19 mm) than samples with lower alpha(s1)-CN level and larger micelles (Boer 31.13 mm and Cross 33.51 mm). Syneresis was significantly higher (P %26lt; 0.001) in milk with good coagulation properties. Curd firmness was negatively correlated with coagulation rate (R, -0.832) and micellar size (R, -0.647). Milk from Arsi-Bale and Somali goats had significantly higher alpha(s1)-CN level, smaller micelle and better cheese making property than the cross and Boer goats. This study shows that there exists high potential among indigenous goats for cheese production.

• 出版日期2014-6