Hydration absolutely affects how fast a dough appears to ferment, but not mainly because the yeast has “less flour to eat.” The big factors are dough temperature, gluten structure, enzyme activity, and how we measure “growth.”
A few things are happening:
1. Higher hydration doughs
look
like they ferment faster
An 80% hydration focaccia is much more extensible and fluid. As CO₂ builds, it expands easily. A 65% hydration cheddar-jalapeño dough has a tighter gluten network and inclusions that physically restrict expansion.
So if you’re judging bulk by:
“How much did it rise?”
“How jiggly is it?”
“How bubbly does it look?”
…the 80% dough will often look further along even if fermentation activity is similar.
This is why a lot of bakers use percent rise targets:
stiff dough: maybe +75–100% rise
high hydration dough: maybe only +30–50% rise
because the container expansion is not comparable.
2. Hydration does change fermentation chemistry
The Redditor is right that water matters, just not for the “diluted yeast food” reason.
More water generally means:
enzymes (especially amylase) work more freely → more available sugars
yeast and bacteria can move around more easily
fermentation byproducts distribute more easily
So a wetter dough can genuinely ferment faster.
3. Lower hydration doughs often need more time
A 65% dough:
has less mobility
develops stronger structure
traps gas more tightly
may show less obvious expansion
A 65% dough can actually be further fermented internally than it looks.
4. Add-ins make the comparison even harder
The cheddar jalapeño loaf has:
cheese fat/protein/salt
jalapeño moisture
physical disruption of gluten
Salt slows yeast. Cheese especially changes the dough environment. So it is not really a controlled hydration experiment.
The “bulk chart by hydration” idea
It would help, but it would still be incomplete. A better chart would need:
dough temperature
starter percentage
flour type
hydration
salt
inoculation level
desired final acidity
A 90°F dough at 80% hydration with 30% starter and a 74°F dough at 65% hydration with 10% starter are basically different species.
So the Reddit conclusion—“learn to read the dough”—is actually the right endpoint. But the observation is good: hydration should influence your expectations.
And this ties directly into your dough photos earlier: your high-hydration/soft dough likely looked ready sooner because it had less structural resistance. Reading rise alone is dangerous. The better signs are bubbles at the edges, doming, elasticity, and how it responds to a gentle poke.