Got a slimy layer on your carrots during storage? I’ve been there before. When I first encountered this, I was frustrated because I could not figure out where I went wrong. But now, I have finally figured out how to avoid these slimy carrots.
In general, carrots with a thin slime layer, that has no foul odor, and still has a firm texture can still be saved and eaten. However, if the carrots already have a thick slime layer, foul odor, and soft texture, it is best to discard them.
Don’t worry, you can still save your slimy carrots! But there are some things you need to consider and know if they are still worth fighting (and eating!) for. Head on to learn more.
If the carrots are slimy but do not have a foul odor, they can be peeled, washed, and eaten safely. However, if the slime is accompanied by a bad odor and softness, it must be discarded as it is a sign of bacterial growth.
Eating slimy carrots depends on how slimy they are. You can measure this by touching, pressing, and smelling the carrots.
When you do check slimy carrots, ask yourself the following questions:
- Touching: Is the slime layer on the carrot thick or thin? Thick slime layers indicate the severity of bacterial infection. Only save the carrots with a thin slime layer.
- Pressing: Is the carrot still firm or is it too soft? Carrots that are too soft must be discarded. Save the firm slimy carrots.
- Smelling: Does it have a bad odor? Discard those with bad odor. Save slimy carrots that smell like normal carrots.
To know more about this, let us discuss the reason why slime layers appear on the surface of carrots.
Slime on carrots is caused by lactic acid bacteria such as Leuconostoc gelidum and Leuconostoc gasicomitatum. These bacteria thrive in the absence of proper ventilation and further result in the soft rotting of carrots.
Slime growth is more highly probable in carrots when there is improper ventilation and there is no oxygen present. This happens in vacuum-sealed carrots and those stored in airtight containers.
Remember that carrots are harvested from the ground. Thus, there are naturally occurring bacteria present in their skins.
When we put carrots in a place where there are no proper conditions for gas exchange, these bacteria do not have a source of oxygen, which is needed for them to respire. But, they have an alternative way to survive. (More of this in the next section!)
Bacterial species like Leuconostoc gelidum and Leuconostoc gasicomitatum, which survive in anaerobic conditions, use sugars present in the carrots to form slimy layers, spread, and survive.
As a continuation of the story above, I want to explain the main difference between respiration in humans and bacteria.
We, humans, cannot breathe without oxygen. However, this is not the case in bacteria, some species are capable of breathing and surviving even in the absence of oxygen! Pretty interesting, right? This is also the reason why they can survive in airtight containers.
In the absence of oxygen, they divert to anaerobic respiration. Anaerobic means “no oxygen”. So simple—it means breathing without oxygen. In this process, bacteria produce acid that we feel as slimy layers.
But what will happen if they stay in this condition for so long?
Soft rotting happens when bacterial colonies do not have oxygen access for a long period. Thus, they infect and consume resources from the carrots themselves.
This is how bacterial rot spreads. In the absence of oxygen, the bacteria have no choice but to consume the carrots’ resources.
As a result, they enter the carrot and infect it, which is why severely damaged carrots are so soft!
A combination of preventive measures and storage management is essential to prevent carrots from being slimy.
Washing carrots with hot water after buying or harvesting them will help in maintaining its surface clean and lessen bacterial populations.
When washing carrots, do the following steps:
- Wash your hands.
- Slice away highly damaged carrot parts.
- Rinse the carrots with clean water.
- Hold and rub the carrots under flowing water.
- (Optional) Clean the carrots using a vegetable brush.
- Pat the carrots in a clean cloth or paper towel.
- Let them dry.
Learn more about this in our article on washing vegetables.
Mechanical damage, in the form of wounds, can elevate the risks of bacterial infestation in carrots. This is due to bacteria having an open pathway to infect the inside of carrots. As a result, it is advised to consume damaged carrots first.
If you accidentally purchased a carrot with some bruised parts, you need to consume it right away. This is to prevent possible microorganism infection.
Don’t worry! It’s safe! Cooking will kill some microorganisms if consumed immediately.
Black spots are another problem with carrots.
Discover more on this topic in our article on reasons for carrot black spots.
A perforated container will help in allowing gas exchange for the carrots. Thus, providing ventilation will not let the bacteria infest the carrots through reproduction under anaerobic respiration and slime production.
As mentioned above, improper ventilation is the main cause of slimy carrots. Thus, pricking holes to plastic bags or using a well-aerated container will help reduce the risks of slime formation.
Cold temperatures slow down bacterial activity, therefore inhibiting them from reproducing and infecting other carrots.
I know you will relate to this one! Whenever I am in a cold room or place, I feel too lazy to move around. The same thing goes with bacteria.
Cold temperatures inhibit bacterial activity, thus, slowing down their growth and reproduction.
The crisper, or low-humidity refrigerator compartment, is ideal for storing vegetables like carrots. Bacteria are deprived of water access, which is required for growth when humidity levels are low.
Remember that bacteria love places with high humidity. Thus, placing them in a place with less humidity will limit the chances of them infecting your carrots!
If the bad odor has not yet affected carrots, one can still save them by peeling and washing them thoroughly.
To do this, follow these easy steps:
- Make sure that your carrots do not have a thick slime, bad odor, and soft texture.
- Wash the carrots initially with slightly hot water.
- Peel the carrots until you could not feel any slime anymore.
- Wash the carrots once again under running water.
- Use them immediately!
What is the difference between carrot slime and carrot mold?
The primary distinction between carrot slime and mold is their causative agents. Bacteria cause carrot slime, whereas fungi cause carrot molds. Furthermore, slime has a distinct appearance because it is transparent, whereas molds have white, hairy growth.
Is the white film growing on your carrots dangerous?
The white film or layer on the surface of the carrot is not harmful. This appearance on the surface of the carrot indicates that it is dehydrated. Washing or soaking the carrots in water will reverse this.
Carrots with thin slime, no odor, and a firm texture can be saved and eaten. But, if the carrots already have a thick slime layer, a foul odor, and a soft texture, the best action is to discard them.
A carrot can become slimy due to improper ventilation. When this happens, bacterial growth is favored and causes carrot soft rot. Slimy carrots with less severity can be saved by peeling and washing them.
- “Baby Carrots – Myth and Facts” by Geiger, M. in Iowa State University
- “Bacterial Soft Rot” by Nunez, J et al. in University of California
- “Carrot” in Texas Agricultural and Mechanical University
- “Food Preservation by Low Temperatures” by Erkmen, O. and Faruk Bozoglu, T. in Food Microbiology: Principles into Practice
- “Leuconostoc gelidum and Leuconostoc gasicomitatum strains dominated the lactic acid bacterium population associated with strong slime formation in an acetic-acid herring preserve” by Lyhs, U et al. in International Journal of Food Microbiology
- “Quality of Shredded Carrots as Affected by Packaging Film and Storage Temperature” by Barry-Ryan, C. et al. in Journal of Food Science