Improved enzymatic method for the rapid determination of histamine in wine

Fermented foods are frequently contaminated by histamine generated by microorganisms possessing histidine decarboxylase activity. The ingestion of large amounts of histamine can cause serious toxicological problems in man. Thus, it becomes important to set a reliable method for rapid histamine quantification in foods. The detection of bacteria exhibiting histidine decarboxylase activity is also important to estimate the risk of contamination of food. Previous enzymatic methods used to quantify histamine in fish gave erroneously high values due to interference when applied to wine. A new enzymatic method is described that allows the direct determination of histamine concentrations in this type of sample. It can be used for the detection of histamine in synthetic media, grape must or wine (white, rose, red) without polyphenols or sugar interferences. This new enzymatic method shows a good correlation (R2 = 0.996, p < 0.001) between the histamine concentrations and absorbances in the interval 0.4-160 mg l(-1). Comparison between this enzymatic method and a high-performance liquid chromatography method showed a high correlation (R2 =0.9987, p<0.001). A miniaturized enzymatic method is also proposed, which is particularly useful when high numbers of samples must be analysed.