Pesticide residue analysis of seabuckthorn juice, oil and related products
Ralf Godeck, Margit Gabriel, Birgit Beddies, Markus Fuchs, Dorota Janas
Gesellschaft für Lebensmittelforschung (GfL) Berlin
++49 / (0)30 / 26 39 20 0
The monitoring of pesticide residues in food is nowadays a priority objective in pesticide research in order to get an extensive evaluation of food quality and to avoid possible risks to human health.
Seabuckthorn juices and oils are used for the production of food and beverages, for instance in cereal chocolate bars, baby food, fruit juices and fruit teas as well as cosmetic products. As for every food product made from fruit and vegetables, a permanent and comprehensive screening for pesticide residues is necessary according to the requirements of food law, especially for baby food, and the regulations for cosmetic products. Furthermore a large proportion of seabuckthorn products is manufactured and put on the market to meet the request for green / ecological certified goods.
A screening method for pesticide residues, including more than 270 fungicides, insecticides, herbicides and other pesticides used worldwide, which is based on a liquid/liquid extraction followed by gel permeation chromatography and capillary gas chromatography and is used as a routine procedure in our laboratory. This method contains the detection of the target compounds using flame photometric, electron capture and thermo inductive detectors and allows the quantification of detected substances in amounts of up to 0.05 – 0.001 ppm. An alternative method using a reduced sample cleaning but mass selective detection is available and provides the possibility of computer aided / software based sample analysis.
The limits of detection are strongly dependent on the sample matrix. While fruit juices and concentrates can be analysed easily, the natural matrix of seabuckthorn oils contains a few compounds that may be critical for the use of several capillary columns and detectors.
During the last 5 years our laboratory has analysed several samples containing seabuckthorn juices and oil, mainly from the German and European market. No significant contents or exceeding amounts of pesticides have been found in samples taken up to now.
An introduction into the used methods will be given in this lecture as well as a summary of the critical points of these analysis methods and the analytical results.