its true you won't have to freak out if you forget to refrigerate biospira when you get home or something. the fact is, the higher the temperature gets, the faster their metabolism increases. the less food there is left in the pouch or bottle, the more bacteria that dies. the more bacteria that dies, the less effective your Bio-Spira is. after paying $15 for a 1oz package, i better place the thing in a refrigerator if i want it to work its best.