Why Can’t You Buy *Fresh* Olives?

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10 Apr 201803:35
EducationalLearning
32 Likes 10 Comments

TLDRThe video script delves into the intriguing world of olives, debunking common misconceptions and revealing the chemistry behind their transformation from bitter, green fruits to the savory, black delicacies we enjoy. It explains that fresh olives are inedible due to their high oleuropein content, which is removed through soaking, fermentation, or a chemical process involving sodium hydroxide (lye). The latter method not only neutralizes the bitterness but also, when combined with oxygen, turns green olives black—a discovery by California farmer Freda Ehmann. The black color can fade, so a fixative is added to maintain the appealing appearance. The video humorously addresses the topic, encouraging viewers to appreciate the role of chemistry in making olives palatable and inviting further questions in the comments for a potential Q&A session.

Takeaways
  • 🌱 Olives grow on trees and are harvested for their fruit, which is naturally very bitter due to a compound called oleuropein.
  • 🛒 You won't find fresh, tree-ripened olives in grocery stores because they are inedible in their natural state due to their bitterness.
  • 🧂 Olives are typically preserved in a salty brine or soaked in water to reduce their bitterness, a process that can take weeks.
  • ⚗️ A chemical method involves using sodium hydroxide (lye) to speed up the breakdown of oleuropein into less bitter compounds.
  • 🚿 After the lye treatment, olives are thoroughly rinsed to ensure no caustic lye remains before they are packed for consumption.
  • 🖤 Black olives start as green and are turned black through a process that involves exposure to oxygen during the lye treatment.
  • 🔁 The presence of oxygen during the lye treatment causes further chemical reactions that create dark brown or black pigments in the olives.
  • 🔄 The color-changing compounds in black olives are not stable and can degrade over time, leading to an unappealing appearance.
  • 🧊 Ferrous gluconate is added as a fixative to stabilize the color of black olives and prevent them from discoloring.
  • 🇺🇸 The process of turning green olives black is known as the Ripe Olive style or California-Style, pioneered by a California farmer named Freda Ehmann.
  • 🍕 Black olives are a popular topping for pizza and are enjoyed by many for their unique flavor, despite their processing from green to black.
  • 🤔 If you prefer your olives less processed and closer to their natural state, look for varieties that have been cured more gently, as oxygen can also affect the flavor compounds.
Q & A

  • Do olives grow on trees?

    -Yes, olives grow on the Olea europaea tree.

  • Why are fresh, tree-ripened olives not commonly found in grocery stores?

    -Fresh olives contain a high amount of a bitter compound called oleuropein, which makes them taste terrible and requires processing to be palatable.

  • Why are olives typically found in a salty brine?

    -Soaking olives in a salt brine is one of the methods used to leach away the bitter oleuropein compound, making the olives more palatable.

  • What is the chemical name for lye and what is it commonly used for?

    -The chemical name for lye is sodium hydroxide (NaOH), and it is commonly used in soap making.

  • How does sodium hydroxide (lye) affect the taste of olives?

    -Sodium hydroxide speeds up the chemical breakdown of oleuropein into less bitter compounds like hydroxytyrosol, improving the taste of olives.

  • Why are black olives actually green?

    -Black olives are actually green when fresh. They turn black through a process that involves exposure to oxygen during the lye treatment, which causes further chemical reactions that create dark pigments.

  • Who is credited with the process that turns green olives black?

    -A California farmer named Freda Ehmann is credited with developing the process that not only preserves olives and improves their taste but also turns them black.

  • What is the purpose of adding ferrous gluconate to the olive processing?

    -Ferrous gluconate is added as a fixative to prevent the olives from turning an unappetizing mottled look due to the degradation of the chemicals that create the dark pigments.

  • What is the Ripe Olive style or California-Style of olive processing?

    -The Ripe Olive style, or California-Style, is a processing method that involves using lye to treat olives, which can result in the olives turning black if oxygen is present during the treatment.

  • Why do some olives remain green after the lye treatment?

    -If no oxygen is present during the lye treatment, the color-changing reactions do not occur, and the olives remain green.

  • How does oxygen affect the flavor of olives?

    -Oxygen can change a lot of the flavor compounds in olives, which is why the more gently cured olives have a different taste compared to the black ones that have undergone the color-changing reactions in the presence of oxygen.

  • What is the final advice given to those who are not fond of olives?

    -If someone does not like olives, the advice is to pass them on to people who do enjoy them.

Outlines
00:00
🫒 The Mysteries of Olive Processing

This paragraph reveals the reason why fresh, tree-ripened olives are not commonly found in grocery stores. It explains the bitterness of fresh olives due to a compound called oleuropein and how it makes up to 14% of the olive's dry weight. The text outlines three methods to reduce the bitterness: soaking in water, fermenting in salt brine, and a chemical shortcut using sodium hydroxide (lye). The lye treatment not only removes the bitterness but also has a secondary effect on the color of the olives, which is further explained in the following paragraphs.

Mindmap
Keywords
💡Olives
Olives are the fruit of the Olea europaea tree, which are commonly known for their use in culinary dishes and for producing olive oil. In the video, it discusses the misconceptions about olives, such as the fact that fresh, tree-ripened olives are rarely found in grocery stores due to their naturally bitter taste. The video also touches on the history and processing of olives to make them palatable.
💡Oleuropein
Oleuropein is a bitter compound found in fresh olives, which contributes to their unpleasant taste when consumed directly from the tree. The video explains that fresh olives contain a significant amount of oleuropein, up to 14% of their dry weight, which is a primary reason why they undergo processing before being sold as a food item.
💡Sodium Hydroxide (Lye)
Sodium hydroxide, commonly known as lye, is a caustic chemical used in the processing of olives to remove the bitter oleuropein. The video describes how lye speeds up the chemical breakdown of oleuropein into less bitter compounds, such as hydroxytyrosol. This chemical treatment is a shortcut that takes about a week, after which the olives are thoroughly rinsed to remove any residual lye before being packed in a salt brine for preservation.
💡Ferrous Gluconate
Ferrous gluconate is used as a fixative in the processing of black olives. The video explains that it helps to stabilize the color of the olives, preventing them from undergoing undesirable color changes over time. By forming a complex with the iron in ferrous gluconate, the olives maintain a shiny, uniform black color, which is characteristic of the Ripe Olive or California-Style processing.
💡Ripe Olive Style (California-Style)
The Ripe Olive style, also known as California-Style, is a method of processing olives that involves the use of lye and oxygen to transform green olives into a black color. The video highlights that this style was developed by a California farmer, Freda Ehmann, as a way to sell her non-oil-producing crop. The process not only changes the color of the olives but also improves their taste, making them more appealing for consumption.
💡Hydroxytyrosol
Hydroxytyrosol is a compound that results from the breakdown of oleuropein when olives are treated with sodium hydroxide. The video explains that this compound is less bitter than oleuropein, contributing to the improved taste of processed olives. Hydroxytyrosol is also involved in the chemical reactions that lead to the darkening of olives when exposed to oxygen during the lye treatment.
💡Brine
Brine is a high-concentration salt solution used in the preservation of olives. The video mentions that after the olives are treated with lye and rinsed, they are packed in a salt brine. This helps to preserve the olives before they are shipped to stores, maintaining their quality and taste during transport and storage.
💡Color Change
The color change in olives is a significant aspect discussed in the video. It explains that the exposure to oxygen during the lye treatment can cause green olives to turn black due to further chemical reactions involving hydroxytyrosol and other compounds. This color change is a distinguishing feature of the Ripe Olive or California-Style processing method.
💡Glycoxidation
While not explicitly mentioned in the video, glycoxidation is a chemical process that can occur in foods, including olives, where sugars react with amino acids or proteins. This process can contribute to the browning of the olives and is related to the formation of the dark pigments when olives are exposed to oxygen during processing.
💡Athena
Athena is the Greek goddess who, according to legend, won the naming rights to the city of Athens by gifting olives. The video uses this mythological reference to highlight the long-standing cultural and historical significance of olives. Athena's gift symbolizes the importance of olives not just as a food source but also as a symbol of peace and prosperity.
💡Olive Oil
Although not the main focus of the video, olive oil is mentioned as another valued product derived from the Olea europaea tree. The video script suggests that while olives are primarily grown for their oil, the fresh fruit itself is not palatable due to its high oleuropein content. Olive oil is produced by pressing the fruit and is known for its health benefits and culinary uses.
Highlights

Olives grow on trees, but fresh, tree-ripened olives are rarely found in grocery stores due to their bitter taste.

Fresh olives contain a high amount (up to 14% dry weight) of a bitter compound called oleuropein.

There are three main methods to remove oleuropein and improve olive taste: soaking in water, fermenting in salt brine, and a chemical shortcut using sodium hydroxide (lye).

Soaking olives in sodium hydroxide speeds up the breakdown of oleuropein into less bitter compounds like hydroxytyrosol.

The lye treatment takes about a week, after which the olives are thoroughly rinsed to remove any residual lye.

Canned olives are packed in a salt brine to help preserve them before shipping.

The lye treatment can also cause green olives to turn black through exposure to oxygen during the process.

A California farmer named Freda Ehmann developed a method in the late 1800s to turn green olives black by mixing air into the lye treatment.

The black color is due to further chemical reactions that create dark brown or black pigments when oxygen is present.

The black color can fade over time, so a fixative called ferrous gluconate is added to maintain the shiny uniform black appearance.

This processing method, known as Ripe Olive style or California-Style, does not apply to all lye-treated olives.

If no oxygen is present during the lye treatment, the olives do not turn black and remain green.

The presence of oxygen can also affect the flavor compounds in the olives, making black olives taste different from more gently cured ones.

Despite the changes in color and flavor, black olives are still popular toppings on pizza.

The video encourages viewers to appreciate the role of chemistry in making olives palatable for consumption.

For those who dislike olives, the video suggests passing them on to others who enjoy them.

The video offers to answer viewer questions about olives in an upcoming Q&A session.

Transcripts

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Olive CuringFood ChemistryLye TreatmentBlack OlivesGreen OlivesOleuropeinHydroxytyrosolFerrou GluconateCalifornia-StyleAthena's GiftPizza Toppings