Bilberries (Vaccinium myrtillus L., Ericaceae) are not only a popular wild fruit but are also used medicinally, e.g. for the symptomatic treatment of mild diarrhoea and to relieve a feeling of heaviness in the legs in cases of mild venous circulatory disorders. The black-blue wild fruits are an expensive commercial product and should not be mixed up with cultivated blueberries (Highbush blueberries, V. corymbosum L.), which show a different profile of secondary plant metabolites. Bilberries are characterised by anthocyanins, which are also responsible for the characteristic colour of the fruits.
In the present study, 11 food supplements were examined. Fresh and dried fruits as well as juices were also analysed for comparison. The following two quality markers were checked for all products (in addition to other parameters 1):
- Authenticity (HPLC / UV detection, fingerprint chromatograms)
- Total anthocyanin content (HPLC / UV detection)
Instrument parameters, analytical conditions and sample chromatograms 1
Conclusion: While the majority of the fruits and juices analysed were of good quality (see publications below), serious quality deficits were found in the segment of food supplements. Almost half of all food supplements examined had to be certified as being of unacceptable quality.
Assessment of the products (incl. illustrations2) The results obtained can be divided into the following categories (colours according to the traffic light principle).
Category 1: Products which fully comply with the declaration or which can be certified as being of very good quality overall (= high anthocyanin content).
Category 2: Products with low anthocyanin content, not recommended
Category 3: Products whose anthocyanin content deviates very strongly from the declaration.
Category 4: Products with an atypical anthocyanin pattern (= authenticity does not correspond !)
Category 5: Products without detectable anthocyanin content
