Eventually, that pressure needs to escape. When it does, the gas mixes with liquid inside the fruit and pushes out as foam or bubbling liquid through cracks in the flesh or rind. Essentially, the watermelon has turned into a small fermentation chamber.
Food safety experts warn that consuming fermented watermelon may expose you to harmful pathogens such as E. coli, Salmonella, or, in rare but severe cases, toxins associated with botulism. The most dangerous part is that the spoilage often starts internally, meaning the rind can look perfectly normal while the inside is already unsafe.
Continued on next pageOther Signs Your Watermelon Has Gone Bad
Foam is one of the most obvious indicators, but it’s not the only one. Watch for these warning signs:
