If the total solution is simply dried down and the yeast is then powdered, all the salts in the solution will be included with the yeast cells. Bees will collect dry yeast from a box left out in the bee yard. Some yeast is carried to the hive and placed in the comb cells, but there is little indication that any is eaten. Placed inside the hive, dry yeast is frequently carried out by the bees. Yeast formulated as moist patties seems to be accepted better by the bees.
Success seems to be better when syrups made of partially inverted sugars are used in the patties.
The fructose attracts and holds moisture, so the patties do not become hard. Diluted honey will have the same properties, but it is teeming with microorganisms that will cause the patty to spoil if the bees do not devour it quickly. Observations made by California beekeepers suggest that yeast feeds should be used when some pollen is still being collected. When pollen is no longer available, interest in consuming pollen substitute appears to become nonexistent. And once you start feeding, do not stop until either the bees lose interest or you no longer wish to rear brood.