Does the subject want to ask "the reason why the bought bamboo shoots have a pungent taste"? The taste of bamboo shoots is not properly stored.

1 Taste of bamboo shoots themselves: Bamboo shoots themselves have a pungent taste, which is because bamboo shoots contain chemicals. You can soak bamboo shoots in water or blanch them with boiling water to remove the odor in bamboo shoots.

2, improper storage: contaminated by bacteria and mold, resulting in a pungent taste.