Several fruit juices and alcoholic beverages (red wine, white wine, apple cider) were treated with different alkaline solutions to examine the best conditions for sulfite liberation. The liquids were diluted 1:100 (v/v) with either carbonate buffer (pH 9.1 and pH 10.6), sodium hydroxide solution (pH 10.3) or with a mixture of 90% carbonate buffer (pH 10.6) and 10% NaOH (1mol/L). After dilu-tion, the mixture was injected into HPLC–IMER seven times within 11htomonitorthechangesinrecoveryovertime.Eachsamplewas analyzed in quintuplicates.