Bread with high moisture content grows mold the fastest. Thus, dark bread like rye, bran, oat and Boston loaves develop mold much faster than dense and dry variants. Moisture in the environment also plays a critical role in how quickly mold spots develop on any type of loaf.

Which bread molds the fastest?

Organic white bread usually molds faster than non-organic white bread because it contains fewer preservatives.

Which bread molds the fastest white or wheat?

In many cases, white bread goes moldy faster than whole wheat bread does. However, storage, preservatives and brand can play a role in how long it takes for mold to form on bread. In general, dense breads build up mold slower than lighter breads, which means that white bread tends to go moldy faster than other types.