The dry yeast, namely instant dry yeast. The current technology can control the moisture between 4%~6%. (yeast moisture is controlled under 5.5%. The mean moisture is about 4.2) It is small granular, and of high fermenting speed. No need to put instant dry yeast into water in advance, but add into the flour directly. The shelf time of instant dry yeast is 24 moths.(Vacuumed packing)
The feature of fresh yeast is high moisture. The moisture is 65%~69%. The fresh yeast is pressed from the manpower cultivated saccharomycetes. For this reason, it looks like a brick. Generally 500g per piece. Even if you bake bread every day, you can only use less than half of it every time. The shelf time of fresh yeast is short. About 40~45 days. Generally, after buying from the supermarket, the shelf time is only about 30 days.