Oligosaccharides in New Zealand sheep milk

Oligosaccharides are a class of carbohydrates formed from chains of 3-10 sugar monomers. They are a natural constituent of milk, where they are found in free form, as glycoproteins when attached to milk proteins and, to a lesser extent, as part of glycolipids. Chemical analysis of oligosaccharides is complex and confounded by the abundance of the disaccharide lactose. In dairy animals such as cows, goats and sheep, lactose is the most common milk sugar (approximately 45-50 g/L). In contrast, the non-lactose oligosaccharide content of dairy milk is much lower (20-60 mg/L) [1], but nevertheless plays an important role in the development of the immune system of the suckling animal. They may have biological benefits for human consumers as well, possibly through prebiotic effects on intestinal microflora. Oligosaccharides attached to milk proteins may also affect the processing of milk and the stability of casein micelles.