Bitter Cucumber – What To Know And How To Fix It

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Cucumbers are delicious and versatile – the green juicy slices are a great addition to salads, sandwiches, and dips. A slice of cucumber sprinkled with salt can make a great tasty snack too! But what if your cucumber tastes bitter? Is it safe to eat, and can you fix it?

So, what do you do if your cucumber tastes bitter? With some careful preparation, a slightly bitter cucumber is safe to eat, and you can use different techniques such as adding seasonings to hide the bitter flavor. However, if your cucumber tastes very bitter, it is safer to discard it and use a different one instead.

If your cucumber tastes bitter when you first bite into a slice, don’t give up! We’ve got all you need to know about bitter cucumbers, including when they are safe to eat and the best ways to fix bitter cucumbers. 

Why Are Cucumbers Bitter?

Cucumbers are members of a vegetable family called Cucurbitaceae. This same family as many other vegetables we may be familiar with – zucchini, pumpkin, squash, watermelon, and melon.

All the vegetables in this family contain a tiny amount of a substance called cucurbitacin, which tastes very bitter and is fairly toxic.

Although we enjoy eating all these vegetables, the purpose of the cucurbitacin is to prevent them from being eaten. Many years ago, the levels of cucurbitacin would have been much higher, to stop herbivores from eating these lovely, juicy vegetables.

We can only imagine how horrible and bitter a cucumber would have tasted when the first human tried to eat it – yuck! Over the years, humans have reduced the amount of cucurbitacin in these vegetables, making them safe to eat.

This was done by careful selection of seeds, picking the ones from fruits with the least bitter flavor. We have also developed a tolerance to cucurbitacin over the centuries, so a small amount does not make us ill when we consume it.

As a word of caution, extra care must be taken with raw zucchini if it tastes bitter. This can have very serious side effects if eaten and must not be treated in the same way as a bitter cucumber. When it comes to zucchini, if in doubt, throw it out!

It can be very disappointing when you taste a cucumber and find it to be bitter. It can also be a worry – how do we know if the cucumber is safe to eat? And can we safely eat it?

Before we can figure any of this out, we need to know why our cucumbers are bitter in the first place. Let’s take a look at the main reasons why your cucumber might be bitter.

Growing Conditions

Although we’ve carefully selected cucumber seeds to reduce the amount of cucurbitacin in the fruits, the plant itself still retains small amounts of this toxic substance.

It is normally concentrated in the roots and leaves of the plant, and most of our cucumber fruits are not affected. And yes, a cucumber is actually a fruit!

However, when things go wrong and the plant is stressed, the amount of cucurbitacin in the cucumber fruit increases.

Things which may cause stress to a cucumber plant include extreme weather, poor levels of nutrients, lack of sunlight, or inconsistent watering.

But once a plant produces a bitter cucumber, this doesn’t mean they’ll all be the same. Once conditions return to normal, the plant will start to produce lovely, crisp cucumbers again.


If you’ve ever been to a farmers’ market, you will know that cucumbers come in many different shapes, sizes and even colors!

Although the ones in stores are commonly all the same, there are actually many different varieties of cucumber plants. Some varieties are naturally more bitter, while others will have no bitterness at all.

These are the most common types of cucumber varieties:

  • English or Hot House cucumbers – often regarded as traditional cucumbers, these are long and green with a smooth, thin skin. They normally have very little bitterness.
  • American slicing cucumbers – normally the most common cucumber in the store, these have a thicker, dark green skin and can be quite bitter.
  • Persian cucumbers – these are smaller than the English or American cucumbers and have a slightly ridged skin. They should not taste bitter.
  • Lemon cucumbers – these round, yellow cucumbers are becoming more popular for their delicious flavor. They should not taste bitter, and also do not taste like a lemon!

Taste Receptors

Some people will find even the slightest hint of bitterness completely unpalatable, and there is good reason for this!

Scientists have discovered that there is a genetic difference between people’s taste receptors on the tongue. 25% of people have inherited bitter taste receptors which are incredibly sensitive – these people will find even the tiniest hint of cucurbitacin unpalatable with a strong bitter taste.

This is a throwback to when many bitter foods were toxic, to protect our foraging ancestors from eating poisonous berries. So next time someone says your cucumber tastes horrible, it might just be down to their genes!

Is It Safe To Eat Bitter Cucumbers?

So, we’ve learned that the cucurbitacin which gives cucumbers their bitter flavor is fairly toxic. And it makes sense that we shouldn’t eat toxic things, right? 

Well, if an entire cucumber is bitter, you should definitely not eat it. In fact, it is unlikely that you’d be able to eat it, even if you try to disguise the bitterness. And this is a good thing, as cucurbitacin toxicity is not fun!

Reactions to cucurbitacin include gastrointestinal upsets with symptoms including nausea, vomiting, and diarrhea. So, if you come across any bitter-tasting member of the cucurbitaceae family – cucumber, pumpkin, zucchini, squash, melon etc. – it is best to stop eating it immediately.

However, you may be able to rescue your bitter cucumber, as long as the whole fruit hasn’t been affected. There are various methods of doing this, but the safest is way to remove the bitter parts. Let’s take a look at how this is done.

How To Remove The Bitter Parts Of The Cucumber

When the bitter cucurbitacin toxins make their way into the cucumber, initially they are concentrated in just a few areas. This makes it easy for us to trim the cucumber and remove the bitter flavor.

It can also help us to figure out if the cucumber is bitter throughout, or just in certain areas.

The bitter compounds enter the cucumber through the stem, so they will be more concentrated at the stem end of the cucumber. They spread just under the skin, so in a mildly bitter cucumber the flesh should be unaffected.

To trim your bitter cucumber, firstly take a slice from the middle of the cucumber and give it a try. Can you detect a bitter flavor? If you’re lucky, it should taste fine, in which case you can just remove the stem end of the cucumber and carry on as normal.

If you can still detect a hint of bitterness in the middle section, you will need to peel your cucumber. Take off the entire skin and a thin layer below, leaving just the flesh of the cucumber. Try a slice of the flesh – is there any bitter flavor remaining?

If the answer is no, then you’ve cracked it! Use the cucumber flesh in the same way as you’d use a whole cucumber.

Just tell your family that you’re serving cucumber in the same way English restaurants prepare them for sandwiches at afternoon tea!

Sadly, if your cucumber flesh still tastes very bitter after peeling, you will need to discard it. If you just have a mildly bitter flavor, you may be able to disguise it, but remember that cucurbitacin is actually toxic, so be careful not to eat too much!

How To Tell If A Cucumber Is Too Bitter

Unfortunately, there is no way to tell that a cucumber is too bitter until you try it.

As the cucurbitacin enters through the stem, it is a good idea to always try a slice from the stem end first before chopping a cucumber for a salad or sandwiches. If this slice tastes fine, then the rest of your cucumber will be perfect too!

Homegrown cucumbers are more likely to be bitter, so take care if growing your own or if friends proudly present their homegrown produce.

Don’t rule out homegrown cucumbers though, as they often taste far superior to the store-bought varieties when grown correctly.

When purchasing a cucumber, go for a variety which is less likely to be bitter, such as English cucumbers. However, even this does not guarantee that your cucumber won’t be bitter!

How To Fix Bitter Cucumbers

If your cucumber is incredibly bitter, then it might be safest to discard it rather than try and fix it.

However, most of us have a level of tolerance to small amounts of cucurbitacin, so if you just have a slight hint of bitterness in your cucumber, then it should be fine to eat.

For all the methods suggested, it is advisable to remove the stem end of the cucumber and peel it first. This means that the areas with the highest concentrations of cucurbitacin have been removed.

1. Add Sugar

A hint of sweetness is sometimes all it takes to hide the bitterness in cucumbers. However, many dishes which contain cucumber will not work well with a sweet flavor, so take care not to add too much.

If you are using cucumber in a yoghurt dip, then a sprinkle of sugar over the cucumber can work perfectly to disguise the bitterness.

Adding a sweeter fruit such as watermelon to a salad can also be a great way to hide a slightly bitter cucumber.

2. Add Salt

Salt is the miracle worker of the food world! It can be used to improve some flavors and disguise others, so if used in the right amounts, it will reduce bitterness and enhance the sweetness of cucumbers.

To add salt to your cucumbers, sprinkle a light amount over the sliced fruit and leave it for about 10 minutes. Water will start come out of the cucumber, so allow this to drain before adding the cucumber to your salad or sandwich.

If you are adding the cucumber to a dish which is already salty, there is no need to salt it first. The salty flavor of the dish will perfectly disguise the bitterness of the cucumber.

3. Use A Vinaigrette

The vinegar base in a vinaigrette dressing can be a great way to hide the bitterness of a cucumber.

The acidic flavor of the vinegar will compete with the bitter flavor – this is why vinaigrette is used to dress bitter salad greens! If you’re using a sweet vinaigrette, then the sugar will also help to disguise the bitter cucumber.

Related Questions

How Do You Fix Soft Cucumbers?

Got a cucumber in your salad drawer which is looking a bit droopy and sad? Don’t panic, we can fix this!

It can be really disappointing to see how quickly cucumbers go soft after we buy them from the store.

These gorgeous salad vegetables (okay, we know they are really a fruit) are delightful when they are fresh – crispy, juicy, and full of flavor. But after a few days, they start to look soft and limp, and not as appetizing.

If you’ve pulled a cucumber out of the refrigerator and it’s looking past it’s prime, check it carefully for mold or slimy parts. These will mean it has started to rot and it should be discarded.

All okay so far? Then its time to rescue your cucumber! This is surprisingly quick and easy to do.

Chop your soft cucumber into slices or chunks, depending on how you want to serve it. Pop them into a colander over a bowl and sprinkle with a large pinch of salt. Toss the cucumber in the salt and leave to stand for 30 minutes.

The salt will draw excess moisture out of the cucumber, and after half an hour, the cucumber should be much firmer and crispier. Rinse the cucumber to remove excess salt, and pat dry with a towel. Voila – your soft cucumber has been revived!

How Do You Keep Cucumbers Crisp?

It is so disappointing when you bring a fresh cucumber home from the store, and it is droopy and soft the next day! There is a secret to keeping cucumbers crisp and fresh, and it is all about how you store them when you get home.

If you are storing a whole cucumber, the trick is to keep them at the right temperature and avoid excess moisture. Wrap the cucumber in paper towel, pop it into a plastic bag but don’t seal the bag – this will help excess moisture to exit the bag.

Always keep them in the refrigerator but ensure that it is not too cold – your cucumber will wilt at temperatures less than 50°F.

Towards the front of middle shelf of the fridge is normally the most suitable place. Keep it away from bananas, tomatoes, and melons, as these all release a gas which speeds up the ripening of the cucumber.

Once your cucumber has been cut, the exposed end will cause the cucumber to become soft and limp much more rapidly.

Covering the end with plastic wrap will slow this process down but cut cucumber will need to be consumed within a couple of days to be at its best.

Got some slices of cucumber left over from lunch or a buffet? These can be stored in an airtight container, laid on a sheet of damp paper towels. This will help the cucumber slices to retain moisture and keep them crisp and fresh.

Up Next: Cucumbers Vs Pickles – What’s The Difference?

One Comment

  1. Hey, Jaron!

    Sometimes you *can* tell if the cucumber will be bitter by smelling the stem end. I and both of my kids can smell bitterness in a cucumber and spice in a jalapeno. (My spouse has a terrible sniffer and cannot smell anything.)

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