Foragers pack raw pollen pellets into comb cells, tamp them down with their heads, and cap the mass with a thin glaze of honey and salivary secretions. Sealed away from oxygen and bathed in hive heat, a community of lactic acid bacteria and yeasts already living on the pollen ferments the mixture over one to three weeks, turning it into bee bread (also called perga) — an acidified, partly pre-digested protein store the colony can keep for months.
Bee bread is more nutritious to the colony than raw pollen: fermentation breaks down tough exine walls and complex sugars, making amino acids and micronutrients far more digestible for nurse bees producing brood food and royal jelly.
A honeycomb patch of capped cells where packed pollen darkens, compresses and releases fermentation gas as lactic acid bacteria convert it into bee bread over roughly three weeks.
Sealed under a honey glaze, pollen pellets are colonised by lactic acid bacteria that lower pH and unlock protein; warmer cells near the broodnest ferment faster than cooler ones.
Drag the fermentation day slider to watch pellets darken and shrink, adjust hive temperature to speed or slow the process, and toggle the honey cap to see why an open cell won't ferment properly.
Bee bread can be stored for months and is the colony's main protein reserve — nurse bees eat it to produce the brood food and royal jelly that raise the next generation.