Are Canned Olives Processed Food? An In-Depth Look at Production and Health

December 9, 2025 •

4 min read

Over 90% of commercially grown olives are used for oil, leaving the remainder for table consumption, but the fruit's natural bitterness means all olives must undergo a curing process before they can be eaten. This necessary step makes even minimally treated olives technically a processed food, though the extent of processing varies significantly by curing method.

Quick Summary

Canned olives are a processed food, altered from their raw state by curing, fermentation, and canning for preservation. The primary health concern stems from high sodium content in brine, while still offering benefits like monounsaturated fats and antioxidants.

Key Points

Processed Classification: Yes, all olives sold as table olives are processed, including canned ones, because they must be cured to remove the natural bitterness.
Industrial Process: Commercial canned olives often use a rapid lye curing method and are heat-pasteurized, which creates a soft texture and kills off any potential probiotics.
High Sodium Content: The main nutritional drawback of canned olives is their very high sodium content from the brine used for preservation.
Retained Nutrients: Despite processing, canned olives retain valuable nutrients like healthy monounsaturated fats, antioxidants (Vitamin E, polyphenols), and fiber.
Naturally Cured Alternatives: Naturally fermented olives found at deli counters are also processed but may retain probiotics and have a firmer texture and more complex flavor.
Moderation is Key: Eating canned olives in moderation is a healthy choice, especially when mindful of the sodium content. Rinsing can help reduce surface salt.

Understanding Processed Food

To answer the question, "Are canned olives processed food?", it's essential to first define what constitutes a processed food. In short, a processed food is any raw agricultural commodity that has been altered from its natural state. This spectrum ranges from minimal processing, like washing and freezing, to heavy or ultra-processing, which involves adding fats, sugars, salt, and other additives. Canned olives fall squarely into the processed category due to the extensive steps required to make them edible and shelf-stable.

The raw fruit from the olive tree is exceptionally bitter and unpalatable. The key to making it a tasty table olive lies in the curing and fermentation process, which leaches out the bitter compound known as oleuropein. For canned olives, this process is industrialized to ensure a uniform, consistent product with a long shelf life, solidifying their classification as a processed food.

The Commercial Process: From Tree to Can

The journey of a canned olive is a multi-step industrial procedure, especially for the commonly found ripe black olives. Here is a simplified breakdown of the commercial canning process:

Harvesting: Olives are harvested mechanically or by hand.
Lye Curing: To quickly remove bitterness, commercial producers often soak the olives in a caustic lye (sodium hydroxide) solution. This is a rapid process, typically taking around 24 hours, versus the weeks or months of natural fermentation.
Color Fixing: For ripe black olives, after lye curing, the olives are exposed to an oxygenated solution to develop a dark color. Iron compounds like ferrous gluconate are added to fix and maintain this uniform black color.
Rinsing and Brining: The olives are repeatedly rinsed to remove excess lye, then fermented and stored in a mild saltwater brine solution. This adds flavor and acts as a preservative.
Sizing and Inspection: Olives are mechanically sorted by size on a shaker table and inspected for quality.
Pitting and Stuffing: Olives may be pitted and/or stuffed with pimentos, garlic, or other ingredients at this stage.
Canning and Pasteurization: The olives are placed in jars or cans with a final brine. Because they are low-acid, they are heat-sterilized through pasteurization to kill harmful bacteria and create a vacuum seal, ensuring long-term preservation. This final step is particularly significant as it kills off any live bacteria, including beneficial probiotics that may have developed during fermentation.

Canned vs. Naturally Cured Olives

Not all processed olives are created equal. The type and degree of processing heavily influence the final product's texture, flavor, and nutritional profile. Naturally cured olives, often found at deli counters, follow a different, more traditional path.

Commercial Canned vs. Naturally Cured Olives


Feature	Commercial Canned Olives	Naturally Cured Olives (e.g., Deli-style)
Processing Method	Uses lye to speed up deburring, often followed by heat pasteurization.	Typically cured over a longer period using only brine, water, or salt. Fermentation occurs naturally.
Sodium Content	Generally very high due to the industrial brining process.	Can also be high in sodium, but naturally cured varieties offer more control and may be rinsed to reduce salt.
Texture	Softer and more uniform, a result of the lye treatment and heat processing.	Can be firmer and chewier, with a more varied texture depending on the curing method.
Probiotic Content	None, as the pasteurization process kills off any beneficial bacteria.	May contain live probiotic cultures due to natural fermentation, offering potential gut health benefits.
Flavor Profile	Milder, less complex flavor profile as a result of the quick lye curing.	Robust, complex flavors with more character, reflecting the olive variety and longer curing process.

The Health Perspective: The Good, the Bad, and the Salty

Despite being a processed food, canned olives are not inherently unhealthy. They are a valuable component of the Mediterranean diet and offer significant nutritional benefits.

The 'Good' News

Healthy Fats: Olives are rich in monounsaturated fats, particularly oleic acid, which is associated with improved heart health, lower cholesterol, and reduced inflammation.
Antioxidants: They contain powerful antioxidants like Vitamin E, polyphenols, and oleuropein, which combat oxidative stress and inflammation.
Fiber: Whole olives provide dietary fiber, which is important for digestive health.
Vitamins and Minerals: They also contain other essential nutrients, including iron, copper, and calcium.

The 'Bad' News: The Sodium Issue

The main nutritional drawback of canned olives is their high sodium content, which comes from the brine used for curing and preservation. A single serving can contribute significantly to an individual's daily sodium intake, and excessive sodium is linked to high blood pressure and an increased risk of heart disease. For those monitoring their salt intake, portion control is critical, and rinsing the olives can help reduce some of the surface salt. Jarred olives, often in a milder brine or oil, can sometimes be a lower-sodium option than canned varieties.

How to Choose the Healthiest Olives

Choosing the healthiest olive isn't about avoiding processed foods entirely, but rather about being an informed consumer. If you are watching your sodium, check the nutrition labels carefully for low-sodium options. If you are interested in potential probiotic benefits, look for naturally fermented, unpasteurized olives, typically found in the refrigerated or deli section. If you simply enjoy the convenience of canned olives, rinse them thoroughly to reduce the sodium and enjoy them in moderation as part of a balanced diet.

Conclusion

So, are canned olives processed food? Unequivocally, yes. However, this label does not make them automatically unhealthy. Canned olives offer a convenient and affordable source of healthy fats, antioxidants, and other nutrients, but their high sodium content necessitates mindful consumption. By understanding the processing methods, reading nutritional labels, and exploring alternatives like naturally cured olives, you can make smarter, healthier choices while still enjoying this flavorful fruit.

Frequently Asked Questions

Yes, it is generally safe to eat canned olives every day as part of a balanced diet, but it is important to be mindful of their high sodium content and practice portion control, especially if you have high blood pressure.

There is no significant nutritional difference between green and black olives, as they are the same fruit harvested at different stages of ripeness. However, their nutritional content can vary based on processing. Black olives are slightly higher in iron, while green and Kalamata olives often have more polyphenols.

To reduce the sodium in canned olives, you can rinse them thoroughly under running water before eating. This will wash off some of the surface salt from the brine.

While both are processed, jarred olives are often cured in a milder brine or oil and may undergo less intense heat processing. Some jarred olives are naturally fermented and unpasteurized, potentially retaining more flavor and probiotics than canned varieties.

Yes, pasteurization (heat sterilization) can destroy the beneficial live probiotic cultures that develop during natural fermentation, though the olives will still retain their healthy fats, fiber, vitamins, and minerals.

Olives offer numerous health benefits, including a high concentration of heart-healthy monounsaturated fats, antioxidants, and fiber. They are also a good source of vitamins E and K, as well as minerals like iron.

No, not all olives are cured with lye. While a common commercial practice for ripe black olives to speed up the process, many artisan or naturally cured olives use only salt brine, water, or dry salt over a longer period.