Mini Titrator for SO2 in Wine Analysis

 

Mi455 for measuring SO2 in wine

Technically, sulphite is a salt or ester of sulfurous acid, but more commonly, sulfur dioxide (SO2). Sulfite is the most effective and widely used preservative in winemaking. It preserves by safeguarding musts and wines against premature oxidation and microscopic life forms that could otherwise spoil wine. It preserves a wine’s freshness, helps maintain its color, and is essential for aging wines beyond their first year without deterioriation. It also inhibits wild yeasts, thereby allowing cultured wine yeasts to dominate the fermentation. Sulfites may be "bound" or "free." Bound SO2 combines with aldehyde compounds, those most responsible for oxidation in wines.

Type of wine Maximum permitted level of SO2 in mg/l
Red 160
White / rose 210
Sweet (above 45 g/l sugar) 400

Mi455 Pump calibration procedure

Fill the 100 mL beaker up to the 50 mL mark with Mi555-001 Standard. Fill the 20 mL beaker up to the 5 mL mark with the Mi555-005 Acid Reagent and add the content to the 50 mL beaker.

Place the stir bar in the beaker and place the beaker into the beaker holder. Place the probe holder on the top of the beaker and secure by turning clockwise. Open refill cap on the ORP electrode and immerse the electrode approximately 2 cm (0.8”) into the sample to be tested. Insert dosing tip into holder. Ensure there is titrant in the dosing tip.

Add the contents of one powder packet of Mi555-006 Stabilizer into the beaker.

Press CAL button. The meter enters in pump calibration mode. Press START STOP in order to start the system calibration. At the end of the calibration, DONE appears for a few seconds and the meter returns to the measurement mode.

SO2 measurement procedure

Fill the 50 mL beaker up to 50 mL mark with the wine sample. Place the beaker into the beaker holder. Fill the 20 mL beaker up to the 5 mL mark with the Mi555-005 Acid Reagent and add the content to the 50 mL beaker.

Place the probe holder on the top of the beaker and secure by turning clockwise. Open refill cap on the ORP electrode and immerse the electrode approximately 2 cm into the sample to be tested. Insert dosing tip into holder. Ensure there is titrant in the dosing tip.

Add the contents of one powder packet of Mi555-006 Stabilizer into the beaker.

Press START STOP in order to start titration. The display will show “----” during titration, along with stirrer and pump tags blinking on the LCD. At the end of the titration, the Sulphur Dioxide concentration is displayed in mg/L (ppm).