A common fraud of vinegar is the addition of ethanol from undeclared botanical sources. Mainly committed for economic gain and pretending of higher quality, the natural properties of the vinegar are tried to enhance or manipulated. Carbon and hydrogen isotopes are able to verify the declared botanical source of the ethanol in the product as well as to detect synthetic ethanol from petrochemicals. Another fraud risk that endangers the authenticity of vinegars is the addition of water in vinegar. Using internal standards (such as the oxygen isotope composition of ethanol), we are able to detect exogenous water in vinegar, regardless the geographical origin of the products.
Vinegar is used globally in kitchens and gastronomy as a preservative or for flavoring foods. There are high quality vinegars on the market which are mainly used directly. Also, vinegar is used in many recipes. Vinegar is a liquid fermented food that contains specified amount of acetic acid and water. It is mainly produced from plants such as grapes, apples, grains or sugar cane and some of its bioactive compounds have shown to be beneficial for health. Adulteration of vinegar to gain economic advantage has become a common practice in recent years.
Organic acids are important compounds in vinegar. Some of them are originally present in raw materials such as grape and apple, others may appear during alcoholic, acetic, or another kind of fermentation. The major organic acid in is acetic acid. Sometimes vinegar might be enriched with cheaper synthetic versions of acetic acid in order to elevate the quality artificially or to gain an economic advantage. This fraudulent substitution of botanical origin of acetic acid can be easily detected analytically be Isotope Analysis and is a common service offered by Imprint Analytics.