In the fruitbody, psilocybin and psilocin tend to accumulate in the caps more than in the stems. The spores are completely free of both psilocybin and psilocin. The total potency varies greatly between species and even between specimens of one species in the same batch. Younger, smaller mushrooms are relatively higher in alkaloids and have a milder taste than larger, mature mushrooms. Mature mycelium contains some amount of psilocybin, which can be extracted with an acidic solution, usually of citric acid or ascorbic acid (Vitamin C). Young mycelium (recently germinated from spores) does not contain appreciable amounts of alkaloids. Most species of hallucinogenic mushrooms also contain small amounts of the psilocybin analogs baeocystin and norbaeocystin. Most psilocybin mushrooms bruise blue when handled.