CHEMetrics Sulfite Test Kits "Titrets"  
Fall Bright, The Winemakers Shoppe

      CHEMetrics Sulfite test kits are based on the “Ripper” chemistry, which employs an io-did-iodate titrant and a starch indicator. The “Ripper” chemistry is used as a screening method throughout the winemaking industry for determining the sulfite content of wines.
         Direct reading titration cells, Titrets^TM, are more convenient and more reliable than other commercially available methods for sulfite determination (i.e. drop count titrations or paper strips).  With Titrets^TM accurate, quantitative results can be obtained in less than two minutes. Because the reagent is sealed under vacuum, the Titrets^TM have a virtually unlimited shelf life.

Since all of the components are contained within the test kit, and no measurements or calculations are required, Titrets^TM are ideal for making determinations either in the lab or at the vat.

 

                                                        TEST PROCEDURE

 

      1.   Collect the sample in any clean, dry container.

      2.      Slide the flexible end of the valve assembly over the 
tapered tip of the ampoule so that it fits snugly.  

     3.      Lift the control bar and insert the Titret into the body of the Titrettor.

 

NOTE: The Titrettor is not a component of the test kit. It must be ordered separately.  Some winemakers do not use it. 

 

       4.      Hold the Titrettor with the sample pipe in the wine sample and press the control bar to snap the pre-scored tip of the Titret.  Because the Titret is sealed under vacuum, the fluid inside may be agitated when the tip snaps.

       5.      With the tip of the sample pipe in the wine sample, press the control bar   firmly but briefly to pull in a small amount of the sample.  The contents will turn a deep blue color.  Wait 30 seconds, and then continue the test.  

        6.      Press the control bar again briefly to allow another small amount of sample to be drawn into the ampoule.

          7.    After each addition, remove the sample pipe from the sample and rock the entire assembly to mix the contents of the Titret.  Watch for a color change FROM BLUE TO COLORLESS, (or the color of your sample).  When the color of the liquid in the Titret changes to COLORLESS you are done taking sample go to # 9.

        8.      Repeat steps 6 and 7 until a permanent color change occurs.  CAUTION:  Do not press the control bar unless the sample pipe is immersed in liquid.

        9.      When the color of the liquid in the Titret changes to COLORLESS, or the color of your sample, remove the 
Titret from the Titrettor.  Hold the Titret in a vertical position and carefully read the test result on the scale opposite the 
liquid level. Results are expressed as ppm (mg/L) free SO₂.