PENNSYLVANIA (WTAJ) — Watermelon season is in full swing and some are being referred to as “foaming watermelons.”

No, foaming watermelons are not a new social media trend, nor something you want to eat. They can actually make you and your family sick.

What is a foaming watermelon?

A foaming watermelon is just that, a watermelon that foams. The foam in these watermelons forms from bacteria feeding off the natural sugars in the fruit, basically, it’s the start of the fermentation process in spoiling food.

One thing that this process needs is heat.

A majority of the country’s watermelon supply is grown in Florida, Texas, California, and Georgia, according to the USDA. They may also come from Delaware, Virginia, Indiana and the Carolinas, among other states. These states, like most others, have experienced record-high heat this summer — heat that could possibly trigger the spoiling and fermentation process while the melons are still on their vines.

What you can do to avoid sickness:

According to the Pennsylvania Department of Agriculture, there’s no way to tell from looking at a watermelon if this process has begun. They also said that while fermentation itself is not a risk, it’s the fermentation in spoiled food that is.

The Pa. Dept. of Agriculture has two bits of advice: Buy local to ensure the freshest product and the shortest trip from the farm, and once you slice watermelon it should be refrigerated — never buy unrefrigerated slices.

Sometimes, watermelon may be far enough along in the process that the liquid or foam starts to seep through the rind.

Watermelon.org says that cut watermelon (kept refrigerated; sealed or wrapped) should be eaten within four days. Whole melons can last in your kitchen for about a week, depending on the heat, and in your fridge for about two weeks.

You should also wash the outside of your melon before cutting it.