Watermelon Foaming: 6 Reasons You Must Know

When watermelons start “foaming,” it could mean they’re rotting. If you continue doing things the same way, your watermelon will always end up rotten. Therefore, you should think about these 6 things to prevent watermelon from foaming.

Hot weather makes food management much more of a challenge. It’s best to shop for groceries no more than once a week if you don’t have a lot of room in your fridge and pantry.

Otherwise, you can count on having to cope with a huge garbage pile. Remember this and cut back on your purchases of watermelon and other similar fruits.

As confirmed by professionals in the field, “foaming” occurs when the pressure inside a watermelon builds up due to overripeness and/or fermentation. It’s likely that “foaming” watermelon is actually rotting.

The significance of a watermelon’s “pop” should not be overlooked, though. Higher water turgor, or the “exploding gene,” found in many conventional varieties, can cause watermelons to split open (or burst).

When the watermelon’s internal pressure becomes too high, it can explode like a volcano or foam up erratically.

Reasons For Watermelon Foaming:

1. Hot Temperature

The first factor that contributes to foaming is the higher temperature. Under the skin of a watermelon, the flesh and sugar keep fermenting, making the watermelon useless in any way.

So, instead of preserving this foamy melon in the refrigerator, throw it out straight away. Your watermelon may break depending on how powerful the foaming process leaves you with the worst stink you’ve ever encountered.

2. fermentation

The underlying mechanism that causes this foaming is the fermentation of sugar into alcohol. This is not a good indicator since the flesh of a watermelon should be completely spherical.

The presence of froth suggests that the meat has fermented and turned rotten. So keep that in mind and get rid of it before the rest of your room reeks.

3. Rotten Flesh

The froth that forms on a piece or slice of watermelon that has been left out in the open for a few hours is caused by decomposing flesh. When you try this slice, you’ll notice a new area around the foamy zone, as well as a subtle acidic flavor.

This slice should be thrown out, and you should consider removing the remaining watermelon from your refrigerator because it won’t stay there long.

You still have time to compost the decomposing meat and feed it to your plants. If you compost the watermelon, there’s no need to toss it away. If you do not compost, simply bag the melon and leave it in a trash can outside.

4. Damaged Course

Because of the damaged skin, the fermentation process may begin quickly. Even if just a little bit of the watermelon skin is destroyed, the entire fruit is harmed, and the sugar begins to ferment instantly.

If the foam is coming from a small hole and the watermelon hasn’t been sitting on your counter for long, the skin is most likely damaged and should be patched before continuing.

5. Over Ripe

Similarly, if the watermelon is overripe or over-matured, the froth will be the same. This melon cannot be saved; your only options are to bag it or compost it.

This fermented melon should not be eaten, and you should go food shopping again to cope with the overripe watermelon issue.

6. Pressure Buildup

Finally, foam forms as a result of increased pressure following fermentation. Even if the melon is in good condition, there is no guarantee that there will be no foaming issues.

The pressure within the melon might build up to the point where the froth breaks through the skin.

So, if the skin hadn’t been injured earlier, your melon might be set to explode. Even after a few hours, the smell of rotting meat will fill the whole kitchen, and a lot of baking soda solution will be needed to get rid of it.

4 Ways to Tell If Your Watermelon Is Bad

Expiration Date

Stick to the watermelon shelf life to prevent unpleasant surprises. This is especially true when buying pre-cut fruit.

There are nitrates present.

One of the best ways to tell if your watermelon is fresh and has naturally ripened is to look for nitrates. Watermelons with yellow rinds and white streaks in the flesh should be avoided.

Crush some pulp and mix it with a glass of water for a tried-and-true approach. If you have a nutritious fruit, the water will become murky. Watermelon with a high nitrate content, on the other hand, has the ability to discolor the water. It is preferable to avoid it.

External Appearance

Depending on the cultivar, watermelon has a constant pine green color with or
without stripes. Any variation from the proper color should cause you to raise
your eyebrows.

Any dark areas of white, fuzzy, green, or black mold on the watermelon skin
indicates that the fruit has spoiled.

The Internal Appearance

  • A decaying watermelon’s flesh will be shriveled, gritty, dry, mushy, or slimy.
  • The color of healthy fruit is a rich pink or pure crimson. To avoid food poisoning, avoid eating anything that is yellow, orange, or black. Remember that certain cultivars have naturally yellow or orange flesh, such as Tender gold, Yellow Doll, Desert King, and Yellow Baby.
  • Watermelon has gone sour if it has a foul odor or smells like vinegar.
  • A watermelon that tastes sour rather than fresh, sweet, and juicy has rotted and should not be eaten.
  • A hollow core implies over-ripeness or the presence of possibly hazardous growth hormones.

6 Ways To Store Watermelon

As previously said, the most straightforward technique for preserving watermelon is to keep it whole and simply cut it before eating.

However, you may keep it in a few convenient places for a time. Let’s have a look at your choices.


Because sliced watermelon is only edible for one day at room temperature, it is preferable to keep the slices in the fridge for a few days. Refrigeration changes the composition of the meat and reduces its nutritional value.

Check for signs of spoilage, wash the skin to prevent dirt from contaminating the meat, and cut clean slices to prevent deterioration. Before putting the fruit in the refrigerator, cover it tightly with plastic wrap.

If you want to conserve rindless watermelon slices, de-seed them and place them in the following containers: recyclable bag The container’s lid is airtight. This method preserves the flavor and freshness of the fruit.


Watermelon may be frozen to extend its shelf life, allowing you to make a smoothie or fresh beverage with tiny cubes even when it’s not in season.

Pureed watermelon may also be used to generate ice cubes, which can be frozen in a cube tray or popsicle form. To produce delectable desserts, blend watermelon with spices, other fruits, and veggies.


Drying watermelon is a good way to keep food fresh because the low water content makes it last longer and keeps it from going bad.

Use a dehydrator to dry watermelon, which allows you to manage the temperature and air circulation during the drying process. Peel the skin and cut the fruit into thin slices before drying.

The therapy will last around 24 hours. If you preserve the pieces carefully, you may use them to make a spicy afternoon snack or candy for your children.


Pickled watermelon is popular in Russia for a reason. You can pickle the entire fruit, rind, or flesh in a hot pickling solution, depending on your preferences and flavor. Most recipes include vinegar, lemon juice, spices, and sugar.

Fill mason jars with sliced or cubed fruit. Bring all of the ingredients to a boil, then pour over the watermelon. Allow the jars to cool completely before sealing and keeping in the pantry.

Candied Watermelon Rinds

Pour sugar syrup over the diced rinds. Simmer the liquid until it has thickened to the consistency of jam. Allow the mixture to cool before adding the cinnamon to improve the flavor.


Making watermelon jelly is a simple procedure. Cook until the juice from the
fruit thickens and becomes translucent. As indicated in the recipe, add the sweetener and pectin.

Wrapping Up

When this happens, some people assume that their watermelon has been poisoned or that their “village people” are trying to get them. ome say they would never buy watermelon again if they didn’t know the “secret” behind the foamy watermelon or the cause of the “outburst.”

What happens when a watermelon “convulses” and bursts? Watermelon has a lot of sugar, and some bacteria and fungi thrive in sugary environments.

Fungi, for example, may quickly absorb and metabolize a broad variety of soluble carbohydrates, such as glucose, xylose, sucrose, and fructose, resulting in fermentation.
Do not eat it, and do not go about your business thinking your fruit has been poisoned or that a “time bomb” has been put in your watermelon.

Split An inconsistent watering schedule, particularly considerable irrigation or rainfall during the latter two weeks of growth, causes fruit split in watermelon.

Even with routine harvesting or mild tapping, the high moisture level puts a lot of pressure on the interior of the fruit, causing it to break apart. It’s also fascinating to consider what happens when a watermelon bursts.

Watermelon splitting can be caused by the “exploding gene,” which is found in many traditional cultivars, or greater water turgor (or bursting).

Inside the watermelon, pressure can build up, causing it to split and burst like a volcano or
foam uncontrollably.