Description
Fast, Accurate Measurement of Free Sulfur Dioxide — No Equipment Required The Accuvin Free SO₂ Test Kit provides a fast, reliable way to measure free sulfur dioxide (SO₂) in both red and white wines, as well as must. Designed for real-world winery conditions, this test requires no sample preparation, no instruments, and no pretreatments—delivering actionable results in just minutes.
Key Benefits
- Measures FREE sulfur dioxide only — the most effective form of SO₂ for wine preservation
- Suitable for red and white wines, including colored and turbid sample.
- No filtration, pretreatment, or adjustments required
- No lab equipment or instrumentation needed
- Results in minutes, ideal for cellar decisions
- Works across a wide pH range
Why Measure Free SOâ‚‚? Total sulfur dioxide (Total SOâ‚‚ = Free + Bound) is not a reliable indicator of preservative effectiveness. Only free SOâ‚‚ actively protects wine against oxidation and microbial spoilage.
- Bound SO₂ can be 30–70% less effective as a preservative
- The amount of bound SOâ‚‚ changes over time, reducing protection even if total SOâ‚‚ appears adequate
- SOâ‚‚ effectiveness is pH-dependent:
- Low-pH wines require less free SOâ‚‚
- High-pH wines require significantly higher free SOâ‚‚ levels to achieve the same protection
This test measures FREE SOâ‚‚ only, giving winemakers the information that actually matters for wine stability and aging.
Test Ranges Included Each kit includes both test ranges:
- Low Range: 0–40 ppm (green cap)
- Typically used for wines with pH ≤ 3.6
- High Range: 40–130 ppm (red cap)
- Common for sweet wines and wines with pH ≥ 3.7
All kits contain a 1:4 ratio of high-range to low-range tests.
What’s Included
-Pre-measured test tubes with rehydration solution
-Low-range and high-range test reagents
-Samplers matched to kit size
-Color comparison chart for result interpretation
Detailed Instructions
Samples of wine or must are used as-is. The Accuvin Free SO₂ test minimizes interference from colored and turbid samples—no filtration or color-removal agents required.
- Pour clear liquid from the tube with the black cap into the reagent tube (green or red cap).
- Cap and shake until powder is fully dissolved (≈1 minute).
- Aspirate sample using the provided sampler (or pipette set to 91 µL).
- Dispense sample into the reagent tube and recap immediately.
- Shake and allow 5 minutes for color development.
- Compare tube color to the chart against a white background. Read under incandescent or natural light for best accuracy.
Storage & Shelf Life
- Store below 80°F (27°C)
- Keep out of direct sunlight
- Product remains effective until the expiration date printed on the container (10 months from manufacture)
Learn More
Click here for more documentation on the Free SO2 Test Kit
You can learn more about the Accuvin wine tests and how they all work together here.
