RESUMOObjetivou-se realizar um estudo sobre o perfil de ácidos graxos e frações proteicas do leite de cabra. A principal característica da gordura desse leite é o alto teor de ácidos graxos de cadeia curta e média, que tem pelo menos duas vezes mais ácidos graxos C4-C10 do que o leite de vaca. Esses ácidos graxos possuem metabolismo diferente dos ácidos graxos de cadeia longa. As proteínas do leite de cabra são constituídas em média de 71% de caseínas, 22% de proteínas do soro (proteínas solúveis) e 7% de nitrogênio não proteico. Em comparação com o leite de vaca, o leite de cabra contém menos caseínas, mais proteínas séricas e mais nitrogênio não proteico. A identificação dos componentes do leite de cabra e a caracterização de suas propriedades poderão servir como ponto inicial para elaboração e implantação de programas para melhoria da qualidade do leite de cabra e seus derivados.Palavras-chave: caprino; gordura; proteína. ABSTRACTThe aim of this study/reviewer was to evaluate the profile of fatty acids and protein fractions on the goat milk. The goat milk has as main characteristic the short and medium fatty acid chain (C4-C10) that is, at least as twice as much of that observed in cow milk. The protein fraction on the goat milk is composed in average by caseins (71%), whey proteins, 22% (soluble proteins) and non-proteic nitrogen (7%). When compared to cow's milk, the goat's milk has less casein, more serum proteins and non-proteic nitrogen. Compared with cow milk, goat milk contains less

Summary Electrophoretic and chromatographic techniques were used to determine water‐soluble peptide profiles aiming to identify the adulteration of buffalo milk mozzarella cheese by the addition of cow's milk. Thus, cheeses were produced with contents of cow's milk varying from 0% to 100%, and the peptides extracted after production and after 20 days of refrigeration. Polyacrylamide gel electrophoresis under denaturing conditions in the presence of sodium dodecyl sulphate (SDS‐PAGE) identified a potential peptide marker of exclusively bovine origin with a size of about 21 kDa for the addition of cow's milk above 30%. Reverse‐phase high‐performance liquid chromatography (RP‐HPLC) indicated the existence of two potential peptides present in higher concentrations in buffalo milk and one exclusive for cow's milk, the latter making it possible to estimate the addition of cow's milk to buffalo milk. Six commercial brands of buffalo mozzarella cheese were evaluated, and indications of adulteration found in four of them.