Peanut butter can develop bubbles on the top if it has started to oxidise and has gone off. If it smells or looks different as well then this could be the cause. Bubbles can also appear due to the normal manufacturing process where air has been whipped into the butter.
This article will explore the top causes of bubbles on the top of peanut butter and what you can do to solve each one.
5 Reasons peanut butter has bubbles
Check out the top reasons peanut butter has bubbles on top.
1. Peanut butter has gone bad
Peanut butter that is exposed to air or high heat for a long time can undergo fermentation, resulting in the formation of bubbles. Natural fungi from the air can land on the peanut butter and will start to digest which can create bubbles.
If fungus or mod has started to form on top fo peanut butter you will usually see dark black, blue or green spots or even white. The peanut butter may smell bad or change color. If any of these things have happened throw your peanut butter out straight away.
To stop peanut butter from fermenting or going off as fast you should store it in a cool, dry cupboard in the dark. You can even store your peanut butter in the fridge. Turn it upside-down and place it near the back. This will help to keep it good for longer and stop it from separating.
2. Manufacturing
Small air pockets can be introduced into peanut butter during the manufacturing process, which can become trapped and create bubbles. This can look like small air bubbles on the surface or throughout.
As long as the peanut butter does not smell or look bad then it is fine to eat.
3. Whipped peanut butter
Peanut butter that is whipped or aerated during the manufacturing process may contain bubbles. Whipped peanut butter is delicious, light and is lower in fat because it contains more air. You will be more likely to see small air bubbles throughout or on the surface.
4. Freezing
Peanut butter that has been frozen and then thawed may contain bubbles due to the expansion of the oil during the freezing process. This can also happen if water or air has been incorporated into the peanut butter before freezing.
You can simply stir the peanut butter when it thaws to work the air bubbles out and mix together any separated ingredients.
5. Shaking or transport
Peanut butter that has been shaken or agitated vigorously may contain bubbles. This can happen during transport or as it is moved onto shelves. Many small companies will vary in the manufacturing process and air bubbles can make their way into the mix.
As long as the peanut butter still smells and looks normal then it is fine to eat. If the texture has changed, if the color is different or if it smells then throw it out.
When you should throw out peanut butter with bubbles
If the peanut butter has changed in the way it looks, smells or tastes, then it is time to throw it out. Check out these 9 times that it is best to get rid of your peanut butter as it might have gone off.
- The peanut butter has passed its expiration date.
- The peanut butter smells rancid or off.
- The peanut butter has mold or visible signs of spoilage. Look out for color changes, spots or white or dark marks.
- The peanut butter has been stored improperly, such as at a high heat. If the peanut butter has been repeatedly heated or has warmed up in the cupboard it might have gone off.
- The peanut butter has been contaminated with other food. If you have double dipped knives or spoons from other food or your mouth then it could be contaminated.
- The packaging of the peanut butter has been damaged or compromised. If your peanut butter jar has a hole or the top covering has been damaged then it is best to get rid of it.
- The peanut butter has been recalled by the manufacturer or regulatory agency due to contamination or other safety concerns.
- The peanut butter has ants in it. Ants are tiny and can work their way into containers. Ants can be attracted to peanut butter due to the fat and protein content.
- The peanut butter has been exposed to extreme heat or cold that may have caused it to spoil or become rancid.
Does peanut butter go bad if unopened?
Peanut butter in a sealed jar can last for a long time. The expiration date can be at least a year from the date that you buy it. As long as the jar is kept in a cool area in the dark it will last well. Natural peanut butter that does not contain preservatives will not last as long.
As soon as you open the jar and scoop some out then it will not last as long. This can allow fungus and bacteria into the peanut butter which can cause it to go off quicker.
Always use clean cutlery when scooping out your peanut butter and keep the lid on tight. This will help it to keep good for longer.
Peanut butter bubbles | Summary
Peanut butter can form bubbles on the surface during the manufacturing process or if the peanut butter has been shaken. Whipped peanut butter will be naturally light and will have tiny air bubbles mixed through. As long as the peanut butter looks and smells good then it will be fine to eat. Throw it out if it is passed its expiration date or looks or smells bad.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.