For the first time, an entire publication has been dedicated to providing a critical review of the identification and analysis of the milk specific proteins such as lactalbumin, lactoferrin and casein; the non-milk specific proteins such as plasma and membrane proteins; and the minor nitrogen-containing components such as enzymes, hormones, and growth factors. Biological roles, whether nutritional, endocrinological or immunological, of the specific nitrogen compounds in mammary milk production and/or growth and development of the breast-fed infant are also presented. Identification of the...