Comparison
Kettle sour vs Lambic
What is the difference between Kettle sour and Lambic?
The short answer
The main difference is funk: Lambic has far more of it than Kettle sour. Kettle sour also leads on carbonation; Lambic on phenolic spice and dryness.
Generated from the two style records. No editor has written this comparison up, so it carries no verdict beyond what the data supports.
Where they overlap
They share comparable acidity, the same style family — the boundary between them is narrower than the comparison suggests.
Side by side
| Kettle sour | Lambic | |
|---|---|---|
| Family | Sour & wild | Sour & wild |
| Fermentation — The clearest structural difference between these two — it shapes everything the yeast contributes. | Mixed fermentation | Spontaneous |
| Origin | United States | Belgium |
| Category status — One of these is a more settled category than the other, which is worth knowing before treating the comparison as exact. | Commercial category | Established |
| Strength | 3.5–6% ABV | 5–6.5% ABV |
| Bitterness (IBU) — IBU measures iso-alpha acids in the lab. It does not track perceived bitterness, which residual sweetness, body and roast all alter — compare the sensory rows below for how each actually tastes. | 2–10 IBU | 0–10 IBU |
| Colour | Straw to fruit-derived colour — 3–20 SRM, 6–39 EBC | Gold to amber — 3–7 SRM, 6–14 EBC |
| Original gravity | 1.036–1.055 | 1.040–1.054 |
| Final gravity | 1.004–1.012 | 1.000–1.010 |
| Serving temperature | 4–8°C | 8–12°C |
| Carbonation | 2–3 vol CO₂ | 0.5–2 vol CO₂ |
| Glassware | Tulip glass | Wit tumbler, Tulip glass |
| Clarity | hazy | slight-haze |
How they taste different
| Character | Kettle sour | Lambic |
|---|---|---|
| Funk | None | High–Very high |
| Phenolic spice | Not characteristic | Low–Moderate |
| Carbonation | High | None–Trace |
| Dryness | Moderate | Very high |
| Yeast fruitiness (esters) | Not characteristic | Low |
| Berry | Low–High | Not characteristic |
| Tropical fruit | Trace–Moderate | Not characteristic |
| Sweetness | Trace–Moderate | None |
Which should you choose?
- You want more funk → Lambic
- You want more carbonation → Kettle sour
Derived from where the two actually differ. Neither is better — this is a question of which difference you want.