How to know if zucchini is spoiled

In this brief article, we will answer the question ‘How to know if zucchini is spoiled’. This article will also discuss the health consequences of eating spoiled zucchini and the proper way of storing zucchini to improve its shelf life.

How to know if zucchini is spoiled?   

To determine if your zucchini is spoiled, you can look for the different signs of spoilage related to its appearance, texture, smell and taste. For example, rotten spots on the skin with a dull skin and sloppy flesh means that the zucchini is spoiled. 

When zucchini goes bad, you will notice that the seeds will be huge once you cut it open. Here, we summarize some general signs that could help you to determine if your zucchini has gone bad:

  1. Wrinkled skin: Once zucchini starts to get old, the skin becomes wrinkly which does not necessarily mean that it is spoiled but the taste might have changed because of the aging.
  1. Bad taste: Taste a little piece of zucchini to check how the taste has changed. If the taste is moldy and tastes acidic then it is better to throw it away. 

Be especially careful if you notice any mold contamination on your zucchini. Remember that molds can produce dangerous mycotoxins that can make you very sick (1-2).

  1. Decaying spots: Dark spots on the skin of zucchini means that it is spoiled. These dark spots are mostly because of bacteria.

You should not eat spoiled zucchini as the different microorganisms growing on it can make you very sick (3-4).

  1. Stringy flesh: Cut into the fruit to check whether the flesh looks plump or not. If the flesh is stringy or you find lumpy growths on the inside with huge seeds then the fruit is spoiled. 

How to identify good zucchini?

When you buy zucchini look for the one which is about 6 to 8 inches long, which is its length after an appropriate harvest. It should not be too hard but instead feel firm with a shiny skin. 

Remember that fresh zucchini has a buttery texture when you cut through it with a fresh yellow to white. 

What does a rubbery zucchini texture mean?

A rubbery texture means that the zucchini is very close to going bad so if you plan to cook it, you should do it immediately. Make sure that you check for any mold growing inside which will mean that it is already spoiled.

Eating zucchini contaminated with molds can lead to severe health problems (1-2). You should never eat spoiled zucchini, especially if it is contaminated with harmful microorganisms.

What is the shelf life of zucchini?

You can keep zucchini at room temperature for 3 days without washing it. Washing the squash will make it age dramatically (5). 

If you store it inside the refrigerator then it will be fresh for a week. You can increase the shelf life by storing the fruit in a cool and dry place which keeps away bacteria.  

Can you get sick from eating spoiled zucchini?

Yes, eating spoiled zucchini can pose various risks to your health. When zucchini spoils, it can become contaminated with harmful pathogens, such as bacteria, viruses, or fungi, that can cause different foodborne illnesses (6). 

These pathogens can multiply and produce toxins, leading to various symptoms when ingested. Here, we summarize some examples of harmful pathogens and the associated symptoms they can cause:

  • Salmonella: Consuming zucchini contaminated with Salmonella bacteria can result in symptoms like nausea, vomiting, abdominal pain, diarrhea (which may be bloody), fever, and headache (7-8).
  • Escherichia coli: Certain strains of E. coli can contaminate spoiled zucchini. Symptoms may include severe abdominal cramps, diarrhea (often bloody), vomiting, and sometimes even a low-grade fever (8).
  • Listeria monocytogenes: This bacteria can contaminate spoiled zucchini and cause a serious infection called listeriosis (9).

Symptoms may include fever, muscle aches, nausea, diarrhea, and, in severe cases, headache, stiff neck, confusion, loss of balance, and convulsions (10).

  • Clostridium botulinum: If zucchini is improperly stored or preserved, it may provide an environment for the growth of C. botulinum, a bacterium that produces a potent neurotoxin (11). 

Ingesting this toxin can lead to botulism, characterized by symptoms such as blurred vision, slurred speech, difficulty swallowing, muscle weakness, and in severe cases, respiratory failure (12).

It is important to note that you should always handle, store, and cook your zucchini properly to minimize the risk of foodborne illnesses following the proper hygiene rules (13).

What should you do if you suspect you have eaten spoiled zucchini?

If you have eaten spoiled zucchini and are experiencing symptoms of foodborne illness, you should assess your symptoms and stay hydrated. 

You should seek medical attention immediately if your symptoms are severe or persistent, and report the illness to local health authorities if necessary.

Finally, remember that you should always practice good hygiene, dispose of remaining zucchini, and prevent future incidents by following proper food safety practices as recommended (13).

How to properly handle zucchini to avoid spoilage?

To properly handle zucchini and avoid spoilage, start by confirming that the zucchini is fresh and firm. 

Then, wrap it in a paper towel to absorb moisture and place it in a plastic bag before storing it in the refrigerator. 

Alternatively, if you prefer dry zucchini, store it in a dark and cool pantry area to prevent moisture. When using zucchini, inspect it for any spoiled areas and cut away any moldy parts, if present. 

To extend its shelf life, you can freeze zucchini by cutting it into small blocks, blanching them briefly in boiling water, drying them, spreading them out on a pan to freeze, and finally transferring them to an airtight container in the freezer. 

This way, the zucchini can remain fresh and be consumed for a few weeks.


In this brief article, we answered ‘How to know if zucchini is spoiled’. This article also discussed the health consequences of eating spoiled zucchini and the proper way of storing zucchini to improve its shelf life.


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