Nature is not always our best friend!
In winemaking, a lot of different types of microbes can alter the quality of wines by producing toxins on the grapes, once they are harvested or during alcoholic and malolactic fermentations.
Wild, indigenous flora – sometimes also named ‘spontaneous’ flora – present on the grapes contain many molds and bacteria that may produce either biogenic amines from amino acids such as histamine, tyramine, putrescine or cadaverine or ochratoxin very early in the process. Botrytis cinerea is responsible for the common gray rot, and is able to produce important quantities of ochratoxin A (OTA).
Compounds such as histamine may have a severe effect on people suffering from intolerance, and the presence of ethanol in wine may enhance the effect of biogenic amines in sensitive people. Many consumers have minor symptoms such as headache or ‘red-face syndrome’ when consuming their first glass of wine. They sometimes don not even know they have an intolerance to histamine.