Comparison of the nutritional value and fatty acid composition of milk from four South American camelid species

Abstract

The nutritional value, whey protein, and the fatty acid (FA) composition of milk from four South American camelids (SAC) (vicuna, Vicugna vicugna (Molina, 1782); alpaca, Vicugna pacos (Linnaeus, 1758); guanaco, Lama guanicoe (Müller, 1776); llama, Lama glama (Linnaeus, 1758)) were evaluated and compared with milk from old-world camelids. Samples were collected from healthy animals from the northwest (llama, alpaca, and vicuna) and Patagonia (guanaco) areas of Argentina. Gross composition of milk from SAC showed a higher protein, lactose, and lipid content than camel milk. Serum albumin and α-lactalbumin were the dominant whey proteins, followed by immunoglobulin G (IgG). The FA profile showed from 4:0 to 24:0 FA, with a high level of conjugated fatty acid (CLA; 1.05–1.64 g/100 g of FAME) and its precursor, vaccenic acid. Desaturase activity of C16 and CLA was quite similar between species but was significantly different for C14. Camelid milk showed a lower atherogenicity index than ruminant milk. This is the first time that a comparative study involving four species of SAC was carried out to contribute to the general knowledge of the physiology of new-world camelids. Their milk was determined to be of high nutritional quality, allowing it to be considered an alternative food item for humans in the semi-arid region of South America.