Food
A food, which may result in allergy symptoms in sensitised individuals.

Allergen Exposure

Geographical distribution
Blackberry is native to Britain. It was always popular as a wild fruit and only developed as a garden fruit about 1850. The Blackberry is an evergreen or semi-evergreen plant with woody, scrambling stems. The ripe fruit is an aggregate of small, purplish-black droplets attached to a cone-shaped receptacle, which readily separates from the plant when the berries are picked. Some 250 species of Blackberry are known. Blackberry is not a real berry but a conglomerate fruit much more closely related to Apple and Peach than to such true berries as Gooseberry, Blueberry and Tomato.

 

Environment
Blackberries can grow wild, mostly in hedgerows or meadows or on the edges of forests, but most commercially available Blackberries are cultivated. The fruit is eaten raw and in pastries, and is used in making syrups, jams and liqueurs. The root can be cooked, and a tea is made from the dried leaves. The young shoots are peeled and eaten in salads. Blackberries are a good source of vitamin C, fibre and folate.

 

The root-bark and the leaves are strongly astringent, depurative, diuretic, tonic and vulnerary. They make an excellent remedy for dysentery, diarrhoea, haemorrhoids, cystitis, etc. Externally, they are used as a gargle to treat sore throats, mouth ulcers, thrush and gum inflammations. Blackberry contains salicylates (natural aspirin)—but these may cause reactions in anyone intolerant to aspirin. Some people find that if they eat the fruit before it is very ripe and quite soft, it gives them stomach upsets.

 

Unexpected exposure
A fibre is obtained from the stem and used to make twine. A purple to dull blue dye is obtained from the fruit.

 

Allergens
No allergens from this plant have yet been characterised

Potential Cross-Reactivity

An extensive cross-reactivity among the different individual species of the Rosaceae family (Almond, Apple, Apricot, etc.), and more specifically the genus Rubus(Cloudberry, Dewberry, Raspberry), could be expected, but this has not been documented as yet (1).

Clinical Experience

IgE-mediated reactions
Blackberry may uncommonly induce symptoms of food allergy in sensitised individuals (2).

 

Although anecdotal reports of allergy to Blackberry have been received, only one report has been published in the medical literature. In a study of four patients with thrombosis associated with antiphospholipid syndrome, each of whom had experienced anaphylaxis attributable to ingestion of vegetables or fruit, one patient was reported to be allergic to Blackberry. The presence of serum IgE specific for a 45 kDa protein band in an Almond extract was detected in all 4 of these patients. No IgE antibodies specific for the food panallergen lipid transfer proteins were detected (2).

 

Other reactions
See under Environment.

Compiled by Dr Harris Steinman, harris@zingsolutions.com