Whey Vinegar is an amber-coloured vinegar made using whey left over from making cheese, or from skim milk.
The whey is first made alcoholic by adding a yeast such as “Kluyveromyces fragilis” to induce fermentation. Then, then after it’s alcohol, a starter culture such as “Acetobacter pasteurianus” is added to convert the alcohol to acetic acid.
The acid level ends up between 5 and 6%.
Fans say it’s good for you, and that they enjoy the “distinctive” taste — which should be all the warning you need to taste it first before you dump it on your salad.
It is made in Switzerland and in New Zealand.
It is considered Dairy under Jewish kosher laws.
Parrondo, Javier et al. Production of Vinegar from Whey. Journal of the Institute of Brewing. 109(4), 356–358, 2003.