Course:FNH200/Projects/2025/Pickled Cucumber

Introduction and history

Pickles are pickled cucumbers that are renown for their acidic and tangy flavor. They are primarily used as a food topping, but can also serve as a standalone food to be snacked on. The word "pickle" originates from the Dutch word pekel, or northern German pókel, which both mean "salt" or "brine". [1]

The process of pickling is one of the oldest methods of food preservation, and is estimated that it had been used in ancient Mesopotamia c. 2400 B.C. Cucumbers arrived in the Tigris Valley from India c. 2030 B.C., where they first began to be pickled and became a popular food source due to their shelf stability. They were one of the first mobile foods, often being eaten by travelers and soldiers. Roman emperors, such as Julius Caesar, believed pickles gave their solders physical and spiritual strength. In c. 850 B.C., Aristotle praised pickles for their healing benefits, while Cleopatra credited pickles for her beauty in c. 50 B.C. [2]

Heinz Kosher Dill Pickles (Discontinued)

Christopher Columbus used pickles as a food source for his crew, like other voyagers in the Age of Exploration. He grew cucumbers in Haiti for pickling in order to restock for his expedition in 1492 A.D., and thus introduced them to New World. [3] In the 16th century, pickles had become a fine food in Dutch cuisine, and by the 1650's, Dutch farmers in New York were harvesting cucumbers for pickling in modern-day Brooklyn. [2]

During the World Wars, pickles were a common food item; 40% of pickle production in the US was sent out for its troops during World War 2. [3]

Processing

Pickling involves immersion of a food in a salt brine for fermentation or an acidic brine, usually vinegar-based. Fermentation creates an anaerobic and acidic environment through bacterial activity, while vinegar brining relies primarily on acidity for preservation, though sealed jars can create anaerobic conditions as well. Both methods extend shelf life and create a unique flavour and texture.

In fermentation, produce with high water content is salted to draw out moisture, creating a brine. The food is submerged in a fermentation vessel, such as a crock or glass jar, and kept at the right temperature (18-22°C) for lactic acid bacteria to thrive. These bacteria convert sugars (glucose, fructose, sucrose) into lactic acid, lowering the pH and preserving the food. Fermented pickles also contain beneficial probiotics and live bacteria not found in vinegar-brined pickles. Sauerkraut, kimchi, and fermented pickled cucumber are common examples [4, 5].

The vinegar-brine method uses a prepared mix of vinegar, water, and salt to quickly acidify food. Because the acidity comes from vinegar rather than microbial activity, vinegar-brined pickles are not considered fermented. This method works for a wide variety of vegetables and fruits [4, 5].

Commercial pickling generally uses a vinegar-salt brine in conjunction with other food preservation techniques such as blanching and the addition of preservatives [6].

A jar of fermenting Sauerkraut

From Cucumbers to Pickles

Pickles in grocery stores are made using a brine made of salt and vinegar. Fermentation is not used in commercially pickling due to the extra time it takes. The vinegar based brine provides acidity (pH < 4.6), which is critical for preventing the growth of Clostridium botulinum and other harmful microorganisms, while heat processing further extends shelf life [7, 8].

1. Harvesting
   • When cucumbers reach the desired size and firmness, they are harvested. Often this is done using mechanical harvesters to remove them from vines quickly. Rapid harvesting preserves freshness and minimizes the time for enzymatic activity and microbial growth that can soften the texture of the cucumber [7, 9].
2. Cleaning and sorting
   • Once the cumbers are at the processing facility, they are washed. This step removes dirt and debris and prepares them to be pickled [9].
   • They are then sorted by size and shape: well-formed cucumbers are kept whole; misshapen or oversized cucumbers are sliced into spears or chips [9].
3. Preparing the brine
   • A hot brine is prepared using vinegar, salt, and sometimes sugar. Spices such as dill, mustard seed, garlic, or turmeric are added for flavour.
     • Vinegar: Lowers pH (< 4.6) to inhibit spoilage and pathogenic bacteria.
     • Salt: Adds flavour and reduces water activity, further limiting microbial growth [7, 8].
     • Sugar: Balances the sharpness of vinegar thus enhancing the flavour. While sugar can reduce water activity, it is usually added in small amounts in vinegar pickles and does not significantly contribute to preservation.
     • Why the brine is hot: Heating dissolves salt and sugar more effectively, reduces the initial microbial load, and pre-warms the cucumbers for more efficient pasteurization. Higher preheating temperatures (around 98 °C) has been shown to improve the final texture of pickled cucumbers compared to lower temperatures. [8]
4. Brining
   • Cucumbers are submerged in large stainless steel tanks or vats of the prepared hot brine [9]. In commercial operations, this step is often brief, just a few hours, since flavour penetration is aided by heat from the brine and later heat processing.

     

     An industrial pickle processing line. [11]

5. Packing and Heat Processing
   • Cucumbers and brine are transferred to sterilized jars, which are sealed and heat processed [9]. Commonly, this is done using pasteurization methods. Heat processing destroys remaining vegetative microorganisms, ensures proper brine sterilization, and creates a vacuum seal upon cooling, preventing recontamination and extending shelf life [10].

Packaging and Storage

Most commercially available pickles are packaged in glass jars, which exhibit many favourable properties. The popularity of glass jars can be attributed to their inert nature, high-temperature tolerance, airtight sealing capability, and transparency. Unlike metal or certain plastics, glass does not interact chemically with the acidic brine typically used in pickling, which helps preserve the flavour and safety of the contents [12]. Glass also has the ability to tolerate high-temperatures, which is required for the thermal processing steps used in commercial pickle production. Airtight lids are used in conjunction with thermal processing by helping to form a vacuum after cooling [13], which prevents contamination and extends shelf life by inhibiting growth of spoilage-causing aerobic microorganisms [14]. Additionally, glass jars allow consumers to visually inspect the contents, which is advantageous for aesthetic presentation. Their reusability and recyclability also contribute to their popularity from both economic and environmental perspectives [15].

During storage, it is recommended that pickles remain fully-submerged in the brine solution to inhibit aerobic microorganism growth. [16] Commercially processed pickles using thermal-processing are shelf-stable at room temperature, but methods that do not include a thermal-processing step require refrigeration to achieve shelf lives of approximately 4 to 6 months [17]. Refrigeration is also required for thermally-processed pickles, but only after their container is opened in order to slow growth of possible contamination and spoilage-causing aerobic microorganisms introduced to air.

Canvas Quiz Question

Glass jars are preferable for pickle packaging for which of the following reasons? (multiple answers)

• High temperature tolerance (Correct)
• Inertness (Correct)
• Mechanical strength (Incorrect)
• Supports aerobic microorganism growth (Incorrect)
• Transparency (Correct)

This question is suitable for the final exam because it requires students to recall a variety of topics covered in FNH 200. These include food packaging materials, thermal food processing, microorganism growth, and consumer preferences. Being able to make connections between different lessons as the questions requires can help to strengthen understanding of the course material.

References

1. Avey T. History in a Jar: Story of Pickles | the History Kitchen [Internet]. PBS Food. 2014. Available from: https://www.pbs.org/food/stories/history-pickles
2. Ralph N, Terebelski D. Pickle History Timeline [Internet]. Nyfoodmuseum.org. 2019. Available from: http://www.nyfoodmuseum.org/_ptime.htm
3. Pruitt S. The Juicy 4,000-Year History of Pickles | HISTORY [Internet]. HISTORY. 2015. Available from: https://www.history.com/articles/pickles-history-timeline
4. Pickling [Internet]. The Culinary Pro. Available from: https://www.theculinarypro.com/pickling
5. Supply MF & F. Home Pickling Basics - What You Need to Know to Get Started [Internet]. Mountain Feed & Farm Supply. Available from: https://www.mountainfeed.com/blogs/learn/15816841-home-pickling-basics-what-you-need-to-know-to-get-started
6. Etchells JL, Bell TA, Fleming HP, Kelling RE, Thompson RL. Suggested procedure for the controlled fermentation of commercially brined pickling cucumbers - The use of starter cultures and reduction of carbon dioxide accumulation. Pickle Pak SCIENCE [Internet]. 1973 [cited 2025 Aug 7];3:4–14. Available from: https://www.ars.usda.gov/ARSUserFiles/60701000/Pickle%20Pubs/p114.pdf
7. Food & Wine. The Science of Vinegar Pickling, Explained [Internet]. Food & Wine. 2017 [cited 2025 Aug 5]. Available from: https://www.foodandwine.com/vegetables/pickled-vegetables/science-vinegar-pickles-explained?
8. Yoo KM, Hwang IK, Eog G, Moon B. Effects of Salts and Preheating Temperature of Brine on the Texture of Pickled Cucumbers. Journal of Food Science. 2006 May 31;71(2):C97–101.
9. Factory Expose. How Pickles Are Made In Factory | Cucumber Pickle Mega Factory [Internet]. YouTube. 2024 [cited 2025 Aug 5]. Available from: https://www.youtube.com/watch?v=9Dik9MyNee4
10. Lee SY. Microbial Safety of Pickled Fruits and Vegetables and Hurdle Technology. Internet Journal of Food Safety [Internet]. 2004 [cited 2025 Aug 4];4:21–32. Available from: https://www.foodhaccp.com/internetjournal/ijfsv4-3.pdf
11. Learn How Pickles Are Made on This Free Pickle Factory Tour [Internet]. Visitindiana.com. 2019 [cited 2025 Aug 10]. Available from: https://www.visitindiana.com/blog/post/pickle-factory-tour/
12. Moeller LA. Evaluation of Fresh Pack Dill Pickle Chips in Pasteurizable Plastic Containers [Internet]. Fashionably Pickled. North Carolina State University; 2012 [cited 2025 Aug 5]. Available from: https://fashionablypickled.com/wp-content/uploads/2019/07/moeller-thesis.pdf
13. National Center for Home Food Preservation - National Center for Home Food Preservation [Internet]. nchfp.uga.edu. Available from: https://nchfp.uga.edu/how/can
14. Rao Y, Qian Y, Tao Y, She X, Li Y, Che Z, et al. Influence of oxygen exposure on fermentation process and sensory qualities of Sichuan pickle (paocai). RSC Advances. 2019;9(66):38520–30.
15. Glass Packaging Institute. Facts About Glass Recycling | Glass Packaging Institute [Internet]. Gpi.org. 2023. Available from: https://www.gpi.org/facts-about-glass-recycling
16. Pickle Fact Sheet [Internet]. Oregon State University Extension Service; 2024 [cited 2025 Aug 7]. Available from: https://oregonstate.app.box.com/s/3yryrptb1op99yjtuywhz10tox9ht63c
17. Garden-Robinson J. Making Pickled Products [Internet]. Available from: https://www.ndsu.edu/agriculture/sites/default/files/2024-08/fn189.pdf