Sheep’s whey is a food which may result in allergy symptoms in sensitised individuals.

Sheep’s Whey Allergy Test: Allergen Exposure

Sheep’s milk (or ewes’ milk) is the milk of domestic sheep, which has been consumed by humans for thousands of years. It has a sweet and soft flavor and aroma and a creamy texture due to the presence of the small fat globules dispersed in the milk. This also makes it more easily digestible.

Sheep’s whey is a byproduct of cheese making, during which sheep’s milk is separated into curds, used to make the cheese, and whey, the remaining liquid part.

Sheep’s whey may sometimes be included in infant formulas such as liquid or powdered milk or baby food. It is also a common constituent of commercially available protein powders or shakes, used by fitness enthusiasts and bodybuilders.

Sheep’s whey has been used in the production of specialist vodka and gin.

Sheep’s Whey Allergy Test: Allergen Description

Sheep’s whey is essentially identical to whole sheep’s milk in terms of its allergenic potential apart from the near complete absence of casein. It contains various whey proteins which may also result in allergy symptoms in sensitised individuals.

Sheep milk is richer in whey proteins than the milks of other domestic animals.

Patients sensitive to the allergens present in sheep’s whey should avoid other foodstuffs where these occur, such as sheep’s milk.

Sheep’s Whey Allergy Test: Potential Cross-Reactivity

Cross-reactivity between sheep’s milk and whey, and cow’s milk and whey might be expected.

In some cases homologous milk proteins of different species can lead to cross‐reactivity in sensitized/allergic individuals.

Studies have shown that some children allergic to sheep’s milk protein can experience allergic reactions after ingesting other domestic animals milk, such as buffalo, goat, cow, donkey, and horse milk.

Sheep’s Whey Allergy Test: Clinical Experience

Sheep’s milk is sometimes recommended as a substitute for cow’s milk in atopic children. However, in one study 15 out of 16 cow’s milk allergic patients also had IgE antibodies against sheep’s milk. Similar cross-reactivity could be expected with sheep’s whey.

Milking sheep or working in sheep dairies can cause IgE mediated respiratory problems in milk allergic individuals.

Anaphylaxis has been reported in an infant after ingestion of a whey protein formula.

As whey proteins are altered by high temperatures, whey-sensitive people may be able to tolerate evaporated, boiled, or sterilized milk.

Hard cheeses are high in casein, but low in whey proteins, and are the least allergenic for those allergic to whey proteins.

Other reactions

Consumption of raw sheep’s milk presents a risk due to the potential presence of undesirable food spoilage or pathogenic bacteria.

Because whey contains lactose, it should be avoided by those who are lactose intolerant. Particularly when used as a food additive, whey may contain lactose levels far in excess of the tolerance of most lactose-intolerant individuals.