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Nature’s Gold Star in Preservation: How Honey Never Expires

  • Raihanna Osayra Rafinal
  • May 28
  • 4 min read

Thousands of years ago, the ancient Egyptians used honey to treat wounds as medicine, and the Romans utilised it for food preservation. Even now, archaeologists have found tubs of honey from millennia ago in ancient Egyptian tombs, still completely edible (Garcia, 2018). Furthermore, some recent studies have further validated honey’s pharmaceutical usage (Arawwawala & Hewageegana, 2017). But how did such a delectable, sweet treat stand the test of time, while others are unable to? How does it compare to other preservatives? Additionally, what properties do they have to make them so useful in not only preservation, but also wound healing and medicine?


Sugars Are More Than Sweet

If not obvious enough from the taste, honey has a high concentration of sugars, approximately 80%. A deeper dive into the biological side of things would show that sugars aren’t only useful for their taste or energy–they also play a key role in maintaining an environment’s concentration gradient. A concentration gradient is established from a difference in concentration between two solutes across a membrane (Robb, 2022). Since honey has a high sugar content, it has a lower concentration of water or water potential than that inside microorganisms, or a hypertonic solution (Ogwu & Izah, 2025). Naturally, osmosis occurs to restore a balance between the water potential in honey (outside of the cell) and inside the cell. Osmosis moves water from a higher water potential to a lower water potential, meaning water moves from inside microbial cells to the honey. This causes the cells to plasmolyse and shrink, disrupting cellular functions, ultimately leading them to dry out and die. This also leads to a lower water activity in honey, at less than 0.6, which is much less than the microorganisms’ suitability at around 0.90-0.95. 


Due to this high concentration of sugars, honey is a better preservative than high fructose corn syrup, with only 76% sugar content (The Science behind Honey’s Natural Preservation Power, 2025). However, what makes honey a better preservative than table sugar, which has a much higher sugar content?


An Acidic Environment

Another part of honey’s composition is its low pH, around 3.0-4.5, which is outside the optimum pH of most microorganisms, as the enzymes they depend on to carry out life functions may only work in a certain pH range. Otherwise, they denature and are unable to survive. Microorganisms in honey must focus their energy on maintaining their internal pH, prioritising survivability. Honey’s acidic nature is sourced from the glucose oxidase enzyme that bees add to nectar (The Science behind Honey’s Natural Preservation Power, 2025). This enzyme helps in the formation of gluconic acid (Manukora, 2023), leading to its low pH. This is one of the reasons honey is a better preservative than table sugar, as table sugar has a mostly neutral pH (Sucrose | 57-50-1, n.d.), much more accommodating of microorganisms than honey.


A Slow Disinfectant

Aside from gluconic acid, the glucose oxidase enzyme also catalyses the conversion of glucose into hydrogen peroxide (H2O2) when water is available. This reaction happens slowly over time and continues to happen as long as there is sugar available (The Science behind Honey’s Natural Preservation Power, 2025). Hydrogen peroxide is an unstable compound, easily releasing its extra oxygen atom as a free radical that readily oxidises other molecules. This is especially useful in destroying microbial cell walls as they are put under oxidative stress, oxidising the proteins and fats they consist of. This destroys their internal processes and pH, as it is no longer completely separated from honey’s acidic environment. Once this happens, hydrogen peroxide can cause further oxidative stress to microbial DNA, breaking the chemical bonds that hold it together, effectively hindering the reproduction of the microorganism (Abdelshafy et al., 2024). This makes hydrogen peroxide key to honey’s antimicrobial effects, allowing it to be used in medicine and wound healing.


The Power of Multiplying Forces

Among all the other factors that contribute to honey’s amazing preservation and antimicrobial effects, it contains many phenolic compounds that work together, creating a multiplicative antimicrobial effect (The Science behind Honey’s Natural Preservation Power, 2025). These include flavonoids and phenolic acids, which are responsible for honey’s antioxidant properties (Cianciosi et al., 2018) and help prevent oxidative degradation of honey. While hydrogen peroxide aims to increase oxidative stress in microorganisms, these phenolic compounds aim to reduce oxidative stress towards honey itself. Phenolic compounds have hydroxyl (-OH) groups, which are able to donate a hydrogen atom or electron to a free radical, neutralising the radical and thereby preventing it from causing oxidation. Although the phenolic compound becomes a radical itself once it donates an electron, it remains stable, meaning it does not cause oxidation (Qi et al., 2025). This multiplicative antioxidative nature from phenolic compounds significantly contributes to honey’s medicinal properties and its self-preservation.


Achieving a long-lasting product that does not expire, whilst providing antimicrobial benefits, cannot be attributed to only one component of honey. The sugar content, acidity, and the presence of hydrogen peroxide and phenolic compounds work together to preserve honey while providing it with antimicrobial and antioxidant properties. As the food science industry grows, further studies into nature’s gold’s numerous biochemical processes could trigger innovation in food preservation, allowing natural preservatives to shine.

References

Abdelshafy, A. M., Hudaa Neetoo, & Fahad Al-Asmari. (2024). Antimicrobial Activity of Hydrogen Peroxide for Application in Food Safety and COVID-19 Mitigation: An Updated Review. Journal of Food Protection, 87(7), 100306–100306. https://doi.org/10.1016/j.jfp.2024.100306

Arawwawala, M., & Hewageegana, sujatha. (2017). Health Benefits and Traditional Uses of Honey: A Review. Journal of Apitherapy, 2(1), 9. https://doi.org/10.5455/ja.20170208043727

Cianciosi, D., Forbes-Hernández, T., Afrin, S., Gasparrini, M., Reboredo-Rodriguez, P., Manna, P., Zhang, J., Bravo Lamas, L., Martínez Flórez, S., Agudo Toyos, P., Quiles, J., Giampieri, F., & Battino, M. (2018). Phenolic Compounds in Honey and Their Associated Health Benefits: a Review. Molecules, 23(9), 2322. https://doi.org/10.3390/molecules23092322

Garcia, H. (2018, July 16). Does Honey Expire? | Nate’s Raw & Unfiltered Honey. Nate’s Honey. https://nateshoney.com/does-honey-expire/

Manukora. (2023, November 9). Manukora. https://manukora.com/blogs/honey-guide/honey-making-process

Ogwu, M. C., & Izah, S. C. (2025). Honey as a Natural Antimicrobial. Antibiotics, 14(3), 255–255. https://doi.org/10.3390/antibiotics14030255

Qi, N., Zhao, W., Xue, C., Zhang, L., Hu, H., Jin, Y., Xue, X., Chen, R., & Zhang, J. (2025). Phenolic Acid and Flavonoid Content Analysis with Antioxidant Activity Assessment in Chinese C. pi. Shen Honey. Molecules, 30(2), 370. https://doi.org/10.3390/molecules30020370



 
 
 

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