01/09/2006 - Donkey milk has been hailed as the secret of long life by a family in Ecuador, but is there any Science behind claims for milk that is supposedly the closest thing to human milk?
The longevity of the world's oldest woman, Maria Esther de Capovilla from Ecuador, was put firmly in the hands of the nutritional wonders of donkey's milk. Mrs. de Capovilla passed away earlier this week at the ripe old age of 116.
Olivier Denys from Belgium's only donkey milk farm, the Asinerie du Pays des Collines at the Château des Mottes, told NutraIngredients.com that he was surprised by the admission.
“We know that donkey milk is very good for your health, for the digestion and intestine, but we hadn't heard that it extended lifetimes,” he said.
Mr. Denys and his partner Marie Tack operate Europe's most productive donkey dairy, yielding between 2,000 and 3,000 litres of milk every year. Half of this production goes into the popular cosmetics range, offering customers donkey milk soaps, crème de bains, beauty cream, and face masks.
The rest goes into donkey milk, which is drunk without the need for pasteurisation.
“There's no need,” said Mr. Denys. “Unlike cow's milk, donkey milk does not contain any bacteria.”
Mr. Denys described the milk as whiter and lighter than cow's milk, with a lower fat content. Indeed, according to Fundamentals of Dairy Chemistry (B. Webb, A. Johnson, J. Alford, AVI Publishing, 1974) donkey milk only contains 0.6 grams of fat per 100 grams of fresh milk, considerably less than the 3.7 grams found in cow's milk.
But it's the protein content that makes it different from cow's milk, said Mr. Denys.
A study by Elisabetta Salimei from the Università degli Studi del Molise, Italy in the journal Animal Research (2004, Vol. 53, pp. 67-78) reported that the average protein content of the milk is 1.72 g per 100 g of milk, and was characterised by low casein and whey protein contents.
“Donkey's milk is the closest milk to human milk,” said Denys.
And that has implications for a lot of people, particularly newborns, since there is said to be no threat of allergy, unlike cow's milk allergy that affects up to 4 per cent of all infants, with 90 per cent usually having grown out of the allergy by the age of three.
The milk also has 60 times the vitamin C content as cow's milk, he said, as well as containing vitamins A, D and E, and is a rich source of calcium and phosphorous, making it quite the nutritional gold mine.
And the milk contains immunoglobulins, proteins that function as antibodies and boost the immune system. This makes the milk very attractive to people with subdued immune function, like cancer patients undertaking chemotherapy, said Mr. Denys.
Amazingly, and perhaps irresponsibly, the Indian Journal of Medical Sciences (Vol. 53, Issue 11, p. 510) ran a news article in November 1999 entitled, “AIDS cure from donkey's milk? 'Immuno-stimulants in milk could provide cure for cancer, TB also'”
The lack of supporting Science in the literature suggests that these claims were wishful thinking, and it seems unlikely that many self-respecting scientists would support such statements, but the statements from Maria Esther de Capovilla's family have seen interest in donkey's milk increase, said Denys.
The news also adds to a growing interest in other milk sources, with reports increasing for the possibilities of milk from animals ranging from sheep to camels.
Any potential success for donkey's milk appears to lie in the health and nutritional markets however, and the Asinerie du Pays des Collines does market its milk as a ‘cure' of 28 bottles of 20 ml, one of each to be drunk each day to help boost the system. Sales are limited to a specific catchment area ranging from Amsterdam to Paris, due to the milk being frozen after milking. A monthly ‘cure' sells for €55 (£37).
Another limitation is the quantity of milk produced. A donkey gives about two litres of milk per day, over three milkings, while a cow can churn out 40 litres in a single milking.
And despite having 84 donkeys in his drove, Mr. Denys revealed that only about 15 jennies are ever on active milk duty.
“It's niche,” he said. “But our production goes up every year, and the market is expanding.”