Did you know that there are dozens of different types of olives in existence?
If you are an olive aficionado, perhaps you did know that.
But if you are a casual olive eater, you may only be familiar with the basic green and black olives which tend to show up in popular dishes and beverages.
If that is the case, you may never have tried Kalamata olives. But there is a good chance that you have heard of them since they are becoming a trendy health food.
Are Kalamata olives worth eating?I will be completely honest here. I am not a fan of olives. Both their flavor and texture are quite the culinary turnoff for me.
So when I tell you that even I am thinking about adding some Kalamata olives to my regular diet, you know that I have good reason to be enthused about them.
In this article, I will introduce you to the Kalamata olive, and tell you all about what makes it special from a nutritional standpoint.
Once you are acquainted with this little fruit's impressive nutritional benefits, you too will be ready to shop for Kalamata olives.
What Are Kalamata Olives?
Kalamata olives are a variety of large olives which hail from Kalamata, Greece, the same city which has given them their name.
Because these olives enjoy PDO status in the European Union, the same type of olives grown outside the Kalamata region are sold under the name "Kalamon olives" instead.
Sometimes you might also see them marketed as "Kalamata-style" olives, or even "Kalamata-type" olives.
Now, you might think that where the olives are grown is of little relevance. But that is not the case.
The reason that it is important is because when the olives are grown in their native region of Greece, they are prepared using traditional means and techniques.
As an example, Greek planters typically will not harvest Kalamata olives until they are completely ripe.
Other producers in other regions may harvest the olives sooner.
As to curing techniques, those may vary significantly even within the Kalamata region.
Sometimes these olives are cured directly in water, while other times they might be cured in salt brine or lye.
Still others are prepared through a special technique known as "dry curing," where the salt is applied on its own without any sort of liquid.
The containers for Kalamata olives may give you details on how they have been cured, but there are visual cues you can check for as well.
If you notice that the olives have a "wrinkled" appearance, this suggests that they were prepared through dry-curing.
After this initial step, the olives are usually then transferred to red wine or red wine vinegar, sometimes a combination, or oil. This completes the curing process.
How can you know whether the olives you are purchasing are direct from Kalamata, or are from some other region?
The easiest way is to look at the name. If they are being sold legally as "Kalamata olives," then they must be from Kalamata.
If they have a different name, then they are almost certainly from elsewhere.
There is nothing "wrong" with purchasing the olives from producers outside of Kalamata, but it is good to know what you are getting.
If you do not see an "Imported" label, that may imply that they were produced locally in your region, rather than overseas.
The label "PDO Kalamata" is probably the single best indicator that the olives you are considering purchasing really are from the Kalamata region.
You can also familiarize yourself with different brands and purchase those that you have come to enjoy from Kalamata.
Kalamata Olives Taste and Appearance
How can you recognize Kalamata olives?
Well, aside from looking for the name "Kalamata" (or "Kalamon," or so forth), you can recognize them by their appearance.
Kalamata olives are larger than many other types of olives, and are shaped much like almonds.
They usually have a deep brownish color, sometimes with an almost reddish or purplish tint.
The darkest Kalamata olives may be close to black.
Some however may be slightly greenish, or even green.
Many people are unaware that the difference between "green" olives and "black" olives is not variety-based.
Instead, it has to do with when olives are harvested.
If an olive is harvested earlier in the growing season, it may be green.
If it is harvested later in the growing season, it may be black.
The black color indicates ripeness.
Because traditional producers in the Kalamata region usually harvest their olives when they are ripe, they usually are dark in color, closer to black than green.
But some producers who harvest earlier (especially outside Kalamata) may produce green olives instead.
While green olives are bitter compared to black olives, curing helps to remove this unwanted flavor and improve the overall profile of an olive.
As both green and black Kalamata and Kalamata-style olives are cured, they do not have a bitter flavor.
That flavor may be described as "rich," fruity," or "bold," with a sharp undertone. Some people can detect the flavor of the wine used for the curing.
The texture is usually described to be "meaty."
Remember, both the texture and the flavors can be influenced by the curing process used, so you should pick olives to purchase which are processed the way you like.
Kalamata Olive Curing Processes
I have already briefly talked about some of the different curing processes which may be used for Kalamata olives, but let's discuss them in a bit more detail now.
Curing in Water
This is the most basic method for curing olives. You just soak them completely in water, which leaches out the oleuropein which makes them bitter.
How long does the process take? Usually olives need to cure in water for at least a few weeks.
It should be noted that even after water-curing is complete, many olives will still retain a bitter edge, though it will be far less pronounced than it was originally.
If you enjoy that hint of bitterness, you may like olives cured in water.
Curing in Brine
When brine is used instead of water, much more oleuropein comes out of the olives.
The reason is that the salt solution which is used causes the olives to ferment.
This takes place over a period of months rather than weeks.
The flavor transformation of brine-cured olives is much more dramatic than that of water-cured olives.
The nutrient profile of the olives is more significantly altered as well.
The formula for the brine can vary from producer to producer, but usually the brine used for Kalamata olives is made using red wine or red wine vinegar.
Curing in Lye
This is precisely what it sounds like. The olives are subjected to immersion in lye.
Usually this involves repeated lye applications in order to make sure the curing process reaches clear down to the center of the olive.
When green olives are cured in lye, sometimes they will then be oxygen-treated in order to turn them black.
Many people believe that black olives are "dyed" for this reason.
In actuality, this is a misnomer, but it is true that some olives take their color from how they are processed, rather than how ripe they were when they were picked.
Don't worry - there is no lye present in fully processed olives.
Dry Curing
This method does not involve immersion.
Instead, salt is spread across the bottom of a container, and then the olives are placed on top of it.
Next, more salt is sprinkled on top of the olives.
More olives can then be layered on top, along with additional salt. This can be done until the container is full.
As the olives cure, they will begin to bleed out their juices, which is why they take on a wrinkled appearance.
Those juices get mixed in with the salt, and it takes on a pasty consistency.
The salt needs to be routinely refreshed for the curing process to remain effective. This goes on for several weeks.
Once the dry curing process is completed, the olives are usually placed inside oil. Typically they will be packaged this way for sale.
A Combination of Methods May Be Used
Now, it should be noted that olives are often processed using more than one curing method.
So for example, some Kalamata olives might initially be cured using water, and then in subsequent stages undergo additional curing in red wine.
Remember, there is no hard rule that Kalamata olives be cured one particular way.
While the Kalamata olives cured in red wine or red wine vinegar are most famous, you can find dry-cured versions for sale as well.
And if you happen to have fresh Kalamata olives off the tree, you can cure them however you want.
Why Kalamata Olives Are So Delicious
Brine curing using red wine or red wine vinegar (as is typical with Kalamata olives) offers the following advantages:
- This process removes more bitterness than water would.
- Unlike lye, brine does not leach out too much natural olive flavor.
- Some people feel that the lye curing process leaves behind an unpleasant aftertaste. This is not present with brine-cured olives. Instead, they are imbued with the delicious added flavor from the wine or vinegar.
The fact that the olives are usually harvested when they are ripe also is relevant to their delicious flavor.
Remember, olives harvested earlier are often more bitter.
Simply waiting to harvest them helps to remove a lot of the bitterness through the natural hand of time, even before the olives are cured.
Nutritional Properties of Kalamata Olives
Now that you know a bit more about the history of Kalamata olives and how they are prepared, let's take a look at their nutritional properties.
Actually, it is pretty hard to find a good summary of the nutrition present in Kalamata olives.
So we'll look at the backs of a few food labels to try and form a picture of the olives' nutritional content.
Tragano Greek Organics (1):Serving size: 2-3 olives
- Calories: 30
- Total fat: 2 g
- Saturated fat: 0.4 g
- Trans fat: 0 g
- Sodium: 170 mg
- Dietary fiber: 0.81 g
- Total sugars: 0.2 g (0 added)
- Protein: 0.24 g
- Calcium: 85.5 mg
- Iron: 0.85 mg
- Potassium: 7.8 mg
That calcium accounts for 8.5% of your daily recommended value, so that is pretty great. The iron is 4.7% of your recommended daily intake.
Gia Russa Kalamata Pitted Olives (2):Serving Size: 4 olives
- Calories: 42
- Total fat: 4.4 g
- Saturated fat: 0.4 g
- Trans fat: 0 g
- Sodium: 266 mg
- Carbs: 0.21 g
- Dietary fiber: 0.4 g
- Sugars: 0 g
- Protein: 0.25 g
- Vitamin A, vitamin C, calcium, and iron: 0%
You can see that much of this information is roughly consistent with what we saw above, but there is a striking difference.
These Kalamata olives are lacking the great iron and calcium content of the ones above.
Roland Pitted Baby Kalamatas Olives (3):Serving Size: 3 olives
Mario Camacho Foods Pitted Snack Olives, Kalamata with a Hint of Thyme (4):Serving Size: 5 olives
- Calories: 25
- Total fat: 2.5 g
- Saturated fat: 0.5 g
- Trans fat: 0 g
- Polyunsaturated fat: 0 g
- Monounsaturated fat: 1.5 g
- Sodium: 240 mg
- Carbs: 1 g
- Protein: 0 g
- "Not a significant source of dietary fiber, sugars, vitamin A, vitamin C, calcium and iron."
So the exact nutritional properties of Kalamata olives depend very much on the product you choose.
This makes sense, considering how diverse the preparation methods are.
The different curing techniques as well as the different fluids the olives are packaged in (olive, vinegar, etc.) would impart or leach various nutrients.
Indeed, you can read a bit more about this in this research study ( 5).
For this reason, it is certainly worth shopping around to find the best olives.
16 Health Benefits of Kalamata Olives
You now know a little bit about the nutritional properties of olives-but what you can find on the back of a food label really only scratches the surface.
Much of the nutritional value of Kalamata olives comes down to the micronutrients and antioxidants they contain.
Kalamata olives could the one of the healthiest type of olives. The following are 16 health benefits of Kalamata olives:
1. Kalamata olives have a healthy fat profile.
First of all, you probably noticed while reading the nutritional facts above that the fat profile of Kalamata olives is quite good.
Then again, if you are not familiar with the different types of fats as denoted by their bonds, you may not be aware that Kalamata olives are a great option.
Let's review. Kalamata olives generally:
- Contain a small amount of saturated fat
- Contain zero trans fats
- Are high in monounsaturated fat
On a chemical level, here is what to know about these types of fats:
- Saturated fats have single bonds
- Monounsaturated fats have double bonds
- Polyunsaturated fats have two bonds or more
A little saturated fat is not bad for you.
A lot of people make the mistake of thinking that it is, but current research asserts that our long-held assumptions about saturated fat are wrong.
Those assumptions were firstly that saturated fat increases cholesterol, and secondly that this always is unhealthy for one's heart.
Since then, researchers have learned that saturated fat increases HDL cholesterol.
Higher HDL cholesterol actually prevents cardiovascular disease ( 6).
LDL particles also become larger when you eat more saturated fat ( 7).
This is another factor which decreases your chances of getting heart disease ( 8).
Researchers also now have conducted more research ( 9) into whether or not LDL cholesterol is increased when people eat more saturated fat, and have failed to find a solid link.
Now, let's talk about the monounsaturated fat content of Kalamata olives.
If you do not know a lot about chemical bonds and fat, you may not realize that the fact that Kalamata olives contain mostly monounsaturated fat is a really good thing.
Oils which contain polyunsaturated fats have more bonds, and that equals less stability under high heat.
So if you cook with oil that is high in polyunsaturated fat, it can easily oxidize.
Oxidation, as you probably are aware, is not something you want to introduce to your body, as it causes free radical damage.
Oil made from Kalamata olives is more stable, so you can cook with it at relatively high temperatures with oxidation at a minimum.
2. Some Kalamata olives are rich in iron.
I have seen some resources act as if all Kalamata olives are high in iron, but I could not find citations for their claims. I will go by my own research, which indicates that there are some products that are rich in iron, but many which contain negligible iron.
You need sufficient iron intake in order for oxygen to circulate through your blood to your entire body ( 10).
This is essential to maintaining the health of all of your tissues as well as your overall well-being.
If you shop for Kalamata olives which have a high iron content, then you have found a delicious way to meet this need.
3. Some Kalamata olives have a high calcium content.
Just as some Kalamata olive products are iron in iron, so some are high in calcium.
Again, this does not seem to be universal.
Calcium is a key nutrient for muscle and nerve health ( 11, 12).
Additionally, you do need calcium to maintain healthy bones, even though its role in preventing fractures may not be as dramatic as once believed ( 13).
When you are shopping for your olives, do not simply make the assumption that they are a good calcium source.
Turn over the jar and check the label to see whether they have significant calcium content or not.
4. You can get your sodium by eating Kalamata olives.
In the western world, a lot of people eat too much sodium.
As such, many of us were taught that it is a "bad" thing, and that we should avoid it at all costs.
Of course, that means that some of us have learned some bad habits. We have come to avoid sodium to the point where we are depriving ourselves of a vital nutrient.
I can certainly say that has been the case with me in the past. Believing salt was bad, I would put as little as possible in my food.
I didn't care that much for a "salty" taste most of the time, so I just reasoned, "Why add salt to my food if I don't really care about it?"
Then one day I read up on how important salt actually is, and I went back to increasing my sodium intake.
Kalamata olives are not naturally high in sodium themselves, but they soak in a lot of sodium content because they are cured in briny solutions.
Sodium is a key electrolyte ( 14). You need it in order to maintain your fluid balance. It also is vital for your muscles and nerves.
If you live in a hot climate, chances are good that you sweat out a lot of sodium each day along with other electrolytes.
You need to restore your lost electrolytes along with your lost fluids.
Indeed, many people are not aware of this, but you can even purchase salt tablets.
Salt tablets are exactly what they sound like - pills made out of concentrated salt.
These tablets are used to treat low blood pressure and symptoms associated with exertion, heat, and heavy loss of electrolytes through seating.
When you take them, you do have to drink a lot of water with them.
I actually keep a bottle of these around, and have found that they can be very helpful from time to time.
They seem to help reduce fatigue and improve function for me when my blood pressure is on the low side.
So the sodium in olives isn't a bad thing. It might even be a good thing, so long as you are not overdoing it.
Just remember that anytime you eat salty foods, you should replenish your fluids as well.
5. In some cases, Kalamata olives can make a good source of dietary fiber.
Olives don't contain a huge amount of fiber-several olives will only give you about 3% of your daily fiber.
But if you like to snack on olives, you might very well eat a dozen at a time.
In that case, you have gotten about 12% of your daily fiber needs met.
Here is some of what fiber can do for you:
- Feed your body's healthy flora (15).
- Help you to feel full (16).
- Speed up weight loss (17).
- Keep blood glucose levels in check, preventing or treating diabetes (18).
- Keep cholesterol levels healthy and prevent heart disease (19).
- Potentially prevent constipation (20).
- Potentially reduce your risk for some cancers (21).
To discover more about the health benefits of fiber, you can read my article, "Why Fiber Is Important and Good For You: Health Benefits Revealed."
You can also check out "25+ High Fiber Foods" (coming soon) to discover more ways to introduce the benefits of fiber into your diet.
6. Kalamata olives contain lots of oleic acid.
Now let's start talking about what you won't usually see on nutritional labels for Kalamata olives.
But this is where the real nutritious value of olives really becomes apparent.
As you already know, there is significant fat content in Kalamata olives.
I have already talked a bit about the nature of that fat content-how most of it is monounsaturated and some of it is saturated.
But now let's talk about the specific types of fatty acids found in these olives - oleic acid in particular.
Oleic acid is what olive oil is famous for.
Researchers have found that it can fight inflammation and protect against diabetes and cardiovascular disease ( 22, 23).
Some animal studies have shown that ( 24) oleic acid may have analgesic effects.
Your brain makes use of oleic acid as well ( 25), and there may be benefits for regulating mood ( 26).
Additionally ( 27), there may be benefits for those who have ADHD.
One of the most exciting studies concerning oleic acid and brain health is this one ( 28) in Neurology.
There were 5,632 participants in the data sample, so it was quite a large study.
The researchers reported,
"There was an inverse relationship between monounsaturated fatty acids (MUFAs) energy intake and cognitive decline."
Obviously this study was a broader one, encompassing monounsaturated fatty acids as a group, not just oleic acid, but as oleic acid is a monounsaturated fat, the data is applicable.
Doubtless you are aware that the Mediterranean diet has received quite a bit of positive press over recent years.
Scientists believe that the prominent use of olive oil in that diet is one of the reasons for its numerous health benefits.
7. These tasty olives are a source of gallic acid.
You probably won't see gallic acid listed on the back of a container of Kalamata olives either.
Nonetheless, it is present, and it is a valuable nutrient.
This phenolic antioxidant can help control body weight and "might be a potential therapeutic intervention for insulin resistance in metabolic diseases ( 29)."
Animal research ( 30) has also been conducted on gallic acid and its impact on cognitive decline.
The researchers in the study above concluded,
"Current findings suggest that GA reduces neural damage and brain amyloid neuropathology and improves cognitive function via free radicals scavenging and inhibiting oligomerization of Aβ but with no effect on healthy rats."
Considering the anti-inflammatory nature of gallic acid ( 31) and the results of these studies, this promising nutrient certainly warrants further research.
8. Hydroxytyrosol is also present in Kalamata olives.
Another powerful polyphenol which you will find in Kalamata olives is hydroxytyrosol.
Researchers have found that hydroxytyrosol helps to shield LDL cholesterol from the harmful effects of oxidation ( 32, 33).
If you check out this paper ( 33), you will discover that this polyphenol has demonstrated "significant results related with cardiovascular diseases, cancer, and acquired immunodeficiency syndrome (AIDS)."
Along with its antioxidant effects, it also helps to reduce inflammation.
The researchers suggest that additional research be conducted into hydroxytyrosol, because "it seems to be a good candidate to reduce the risk of diseases mentioned."
9. Oleocanthal in Kalamata olives can help fight inflammation and more.
Another amazing compound in Kalamata olives is oleocanthal.
Oleocanthal has been the subject of cancer research. In this research ( 34), it was found that,
"We investigated the effect of OC on human cancer cell lines in culture and found that OC induced cell death in all cancer cells examined as rapidly as 30 minutes after treatment in the absence of serum."
The researchers also reported that the healthy cells were not damaged by the treatment.
Additionally, oleocanthal showcases powerful anti-inflammatory properties ( 35).
The study above describes how this not only may help with treating cancer, but may also have benefits for joint and brain health.
10. Oleuropein imparts powerful health effects on the heart and brain.
If you have ever wondered why olives taste so bitter, it is due to the presence of oleuropein.
Oleuropein is a potent antioxidant ( 36) and has an anti-inflammatory effect in the body. It is antiviral, antimicrobial, and neuroprotective.
It is also healthy for your cardiovascular system ( 37).
11. Tyrosol in Kalamata olives can help you to control LDL cholesterol.
Kalamata olives also contain an antioxidant known as tyrosol ( 38).
This compound is present in a higher concentration in olives than in other foods or beverages (i.e. red wine).
The tyrosol in Kalamata olives helps to prevent LDL cholesterol from oxidizing.
This improves your cardiovascular health.
12. Olive oil can help reduce the chances of cardiovascular disease.
As mentioned above, the tyrosol which is present in Kalamata olives can help to protect your cardiovascular system.
Indeed, it has been demonstrated that consuming olive oil may help to reduce the risk of cardiovascular disease by as much as 35% ( 39).
The study above looked at more than 7,000 participants, so there is quite a bit of data backing this up.
Another study looked at Greek men ( 40) and compared them to North American and European men.
The researchers found that the men in Greece were living longer on average. This may be due to the higher levels of HDL cholesterol in their bodies.
Another intriguing study ( 41) looked at the short-term effects of extra-virgin olive oil.
One group of subjects ate a meal without any olive oil, while the other group ate the same meal with 10g of extra-virgin olive oil.
After the groups consumed their meals, they were monitored for two hours. They were also monitored in the two hours leading up to the meals.
Researchers found that the cardiovascular markers for the group which consumed the olive oil were superior to those of the control group.
They referred to their oxidized LDL and blood glucose as both being "significantly lower."
Another study ( 42) took a look specifically at metabolic syndrome patients.
Each patient was assigned to one of four different groups for the experiment.
One group ate what they normally did without any supplements.
Another ate their regular meals along with 3 g of fish oil.
Another group ate the meals along with 10 g of extra-virgin olive oil.
The fourth group ate the meals, the EVOO and the fish oil.
There were improvements in all three experimental groups compared to the control group when it came to LDL and HDL cholesterol along with oxidative stress.
The group which achieved the best results was the one which ate both the olive oil and the fish oil.
13. It is possible that Kalamata olives could help prevent or treat cancer.
I have already talked a bit about the ways in which Kalamata olives could potentially be helpful for those looking to prevent or treat cancer, but let's get into it a little bit more.
This meta-analysis ( 43) examined 19 studies for a total of 13,800 patients. It was found that cancer prevalence was inversely correlated with the consumption of olive oil.
In other words, those who consumed the most olive oil were least likely to develop cancer.
Another study worth looking at is this one ( 44).
The researchers divided the participants into three different groups.
Each of the groups consumed a different diet.
All three groups ate a diet which was strongly Mediterranean.
The control group didn't add anything to this diet. The second group ate the same food, but added olive oil. The third ate the same diet, but added nuts instead.
Both the olive oil and the nuts were associated with lower breast cancer rates.
The results for the olive oil were more dramatic.
Those who ate the olive oil were half as likely as those in the nuts group to develop breast cancer.
They were three times less likely to develop breast cancer than the control group which consumed neither olive oil nor nuts.
14. Kalamata olives may be a good choice for preventing dementia.
Researchers have found that people who live in the Mediterranean area are less likely overall to develop dementia.
They tend to live longer as well ( 45, 46).
In animal studies ( 47), it has been found that olive oil consumption can decrease brain oxidization.
Owing to the presence of oleocanthal, olive oil also appears to help prevent the buildup of amyloid plaques in the brain ( 48).
These plaques may be connected to the development of dementia.
More research in this area is certainly warranted since dementia is a rising epidemic.
15. Kalamata olives can help fight diabetes.
In this study ( 49), pre-diabetic participants were split into two groups.
One group ate a meal on its own, while the other group ate the same meal with 10 g of extra-virgin olive oil.
It was found that blood glucose and triglycerides were lower after eating in the experimental group than in the control group.
Also of interest is this meta-analysis ( 50) which looked at 15,000 patients with type 2 diabetes.
29 trials and 4 cohort studies were included in the review.
It was discovered that the best glycemic control was exhibited by those patients which were consuming the most olive oil.
16. There's nothing quite as delightful as a delicious Kalamata olive!
Finally, one last benefit of Kalamata olives is that they are delicious!
While that is subjective and obviously not easy to measure, it can exert a positive influence too.
When we eat foods we enjoy, that is good for our psychological well-being.
Olives are versatile and easy to cook with as well. You can incorporate them into a wide range of recipes with little effort.
Even if you don't want to eat Kalamata olives or import them, you can still enjoy their health benefits by cooking using Kalamata olive oil.
That means you do not even need to make an "olive" related recipe to enjoy the benefits of Kalamata olives!
How to Cure Your Own Kalamata Olives
Let's say you happen to live in an area where Kalamata-type olives grow, and you want to cure your own fresh olives.
How do you do it?
- First, harvest your olives. Wait for them to get ripe. You can tell they are ready to pick when they are a reddish or purplish color. Make sure you do not wait too long. You do not want them to get soft. Those which are wrinkled also need to be tossed aside.
- Now you need to clean your olives and remove the stems and leaves.
- What liquid you store the olives in is also up to you, but wine vinegar is a good choice. You can also add in seasonings such as oregano and salt. Do not dilute the vinegar with water. Make sure that the spices have been distributed evenly through the jar. Shaking it up can help do this once the jar is sealed.
Because the olives have been cured, they have also been preserved.
This means that you can store them safely for up to several years at a time, so long as they are in a cool, dark place.
Indeed, you can eat your freshly-cured olives right away, but it is not recommended.
The flavors need more time to fully integrate, so the olives are actually better after they have been kept in the jars for a period of at least a few weeks.
In fact, several months is ideal.
Curing your own olives can be a rewarding experience, because you get to tailor the process to your exact tastes.
Indeed, it may become something you are passionate about. You might even find a market to sell your olives.
They also make fantastic gifts. If you are feeling fancy, add a ribbon and a tag or a custom label.
Conclusion
Kalamata olives may not be as famous as the olives you usually find in your drinks or on your pizzas, but they offer a unique flavor and a wonderful nutritional profile.
If you have yet to try them, be sure and check your grocery store or order some online. Your body and your taste buds will thank you!
