The foaming and frothing coming out of the watermelon, as shown in your image, is a clear sign of fermentation. This usually means:
- Bacteria or yeast has gotten inside the fruit, likely through a small crack or puncture.
- The fermentation process is producing gas and foam — similar to what happens when beer or wine is brewed.
- The internal pressure builds up, and juice can start leaking or bubbling out, often with a sour or alcoholic smell.
⚠️ What You Should Do:
- Do not eat it. Fermented watermelon can be dangerous to consume due to possible bacterial contamination, including harmful types like Salmonella or Listeria.
- Dispose of it immediately in a sealed trash bag to avoid spreading the smell or contamination.
- Clean the area where it was resting with disinfectant.
In the Future:
- Always check for:
- Strange smells
- Soft, mushy spots
- Unusual sounds (some fermented ones can “pop” or hiss when cut)
- Leaking juice or foam
- Store whole watermelons in a cool, dry place and consume them within a reasonable timeframe (usually within a week or two at room temperature or longer if refrigerated).