WW ASB 14-02
Wine quality control: Screening of regulated substances
Stellenbosch University. Department of Viticulture and Oenology
Hiten, N F
There has been growing pressure on the South African wine industry to prove the quality of its products to its overseas clients. Certificates of analysis for certain unwanted substances i.e. natamycin, ochratoxin A and sorbic acid, in wine are required by many producers in order to show compliance with the exporting regulations. The costs of these analyses will increase as compounds are added to the list, which have a financial impact in the industry. It is important to act in a pro-active way to develop sensitive, efficient and cost effective methods to deal with this problem.
Currently most regulated banned substances in wine including natamycin, ochratoxin A and sorbic acid have to be analysed separately and therefore at a higher cost than if the compounds are analysed together.
The project will also investigate other high risk compounds sometimes present in wines such as phthalates, other mycotoxins like fumonisin, colourants, and biogenic amines such as histamine, tryptamine and tyramine. It is possible that some of these compounds will be included on the list of regulated substances in the near future. At that stage, being ready to screen wine for these substances will avoid the delays associated with the development and implementation of new methods and will save the producers the costs related to the disruption in exports.
Liquid-chromatography mass spectrometry (LC-MS) is the technique of choice for trace level determinations of these regulated compounds. The LC-MS conditions in the current methods for sorbic acid, ochratoxin and natamycin are similar. The most differences are related to the sample preparation. New sample preparation methods have to be developed that will enable the accurate determination of these compounds. Different LC-MS analysis conditions have to be evaluated to compensate for the new sample preparation procedures.
The objectives are:
1. Establish a robust and fast routine screening method for regulated substances
2. Establish robust and fast routine methods for high risk substances (biogenic amines, phthalates, colourants).
Buica, A, Stander, M. 2015. Wine quality control: screening for high-risk compounds.
Poster presented at the 9th Symposium In Vino Analytica Scientia. 14-17 July, Mezzocorona, Italy.