酵母换算器——鲜酵母、活性干酵母、速溶酵母

计算原理

Every conversion routes through a fresh-yeast baseline. Your amount is first turned into grams, then scaled to fresh yeast — active dry doubles, instant triples, and sourdough starter is divided by twenty — and the four equivalents are read back off that baseline as fresh, fresh ÷ 2, fresh ÷ 3 and fresh × 20. Volume entries are converted with per-teaspoon densities of 5.6 g fresh, 3.1 g active dry, 3.1 g instant and 4.8 g starter, with a tablespoon counted as three teaspoons.

Source yeast type is the input that changes everything, since it sets both the density used for teaspoons and the ratio applied. It defaults to Active dry with 10 grams. Pick the type printed on the packet you actually own, not the one your recipe assumes. The headline shows instant when your source is active dry and active dry otherwise, while the table underneath always lists all four types side by side with their weights, volumes and handling notes.

These are the round industry ratios, not laboratory values; real cell counts differ between brands and with the age of the yeast, and fresh yeast loses strength within a fortnight. The starter figure assumes a lively 100 % hydration culture, and the tool does not rebalance your dough — you must cut recipe flour and water by half the starter weight each. Swapping types keeps the rise power roughly equal but not the schedule, since sourdough ferments far more slowly than commercial yeast.

常见问题