Tartaric acid is the strongest of the three organic/plant acids used in winemaking. In wine or mead making it is used to lower PH and raise total/tartaric acidity(TA). In beer making it can be used to adjust brewing water PH. When added to sanitizing solutions like metabisulfite, iodophor or chlorine tartaric acid lowers their PH which greatly improves their effectiveness. Use 1/2-1 tsp per gallon of cleaning solution.