Swap yeast types and work out how long the dough really needs
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A recipe that says "7 g of yeast" almost never says which one it means, and the three types are different strengths by weight because they contain different amounts of water. Fresh yeast is around 70% water. Active dried is around 8%. Instant is drier still and milled finer, so more of it is working surface.
| If the recipe says | Fresh | Active dried | Instant |
|---|---|---|---|
| Fresh yeast | 1 | ÷ 2 | ÷ 3 |
| Active dried | × 2 | 1 | × 0.75 |
| Instant | × 3 | × 1.33 | 1 |
Active dried yeast should be softened in some of the recipe's warm liquid for about ten minutes before it goes near the flour. Instant yeast does not — it can be stirred straight into the dry ingredients, which is the main reason people prefer it. Fresh yeast crumbles into the liquid and dissolves almost at once.
Bakers often reach for more yeast when a dough is slow, but temperature is the bigger lever by far. A dough proving in a 17 °C kitchen will take roughly twice as long as the same dough at 27 °C. Adding yeast to force it along trades flavour for speed: a slower, cooler prove develops far more taste.
If you need to slow a dough down deliberately — to bake in the morning, say — the fridge is the tool. An overnight cold prove at 4 °C is a standard technique, not a compromise.
Yeast does not scale in a straight line when you make a much bigger batch. Double a loaf and doubling the yeast is fine. Take a recipe up ten times and the same multiplication tends to over-prove it, because a larger dough holds its own heat. Scale the yeast by a little less than the flour and give it longer.
Recipes say "7 g yeast" without saying which kind, and the three types are not interchangeable gram for gram. This converts between them and then estimates how long the prove will actually take at your kitchen temperature, which matters far more than the clock time printed in the book.
