15g fresh yeast is 5g dry yeast. According to relevant public information, fresh yeast and dry yeast are different types of yeast, and their dosage is also different. If it is necessary to replace fresh yeast with dry yeast, it can be converted according to the ratio of 1: 3, that is, 3 grams of dry yeast can replace 15 grams of fresh yeast. So 15g fresh yeast is equivalent to 5g dry yeast. The actual conversion ratio will be different due to different brands, different formulas and different environmental conditions, and the amount of dry yeast will be determined according to the requirements of specific formulas.