Now, let’s get specific about mold. White, fuzzy patches are a big no-no. Unlike with hard cheese, you can’t just cut around the mold on a zucchini—its high water content allows mold roots to penetrate deep into the flesh, invisible to the naked eye.
If you see black spots or a pinkish discoloration, that’s even worse. These are signs of advanced decay and potential bacterial growth. In short: when in doubt, throw it out.
The Bitter Truth
Occasionally, you’ll cut into a perfectly firm, green zucchini, only to taste an intense bitterness. This is rare, but it’s caused by a compound called cucurbitacin, a natural defense mechanism that can spike from stress during growth or improper storage.
While it won’t kill you, it’s genuinely unpleasant and can cause stomach upset. If your cooked dish suddenly tastes like a chemistry experiment, that’s your cue to bail on the batch. A good zucchini should taste mild, grassy, and slightly sweet.
