In another experiment, the sulfite-liberating effect of adding pure NaOH (c = 1mol/L) to the sample prior to dilution with carbonate buffer, was shown to be even stronger than the effect of adding NaOH and buffer at the same time. Generally, the maxi-mum sulfite concentration was detected after about 60–100min. The increase in sulfite findings over time was not the same for all sample materials. Whereas for a grape juice, the effect was very small, the bound sulfites of the rosé wine were liberated only upontreatmentwithsodiumhydroxidesolutionpriortoadditionof buffer.