Honey is an amazing natural food product that seems to defy the laws of nature. Most foods will eventually spoil due to exposure to microbes, enzymes, light, air or moisture. Yet honey can remain edible for decades, even centuries, without spoiling!
So why does honey never seem to go bad? The short answer is that honey contains natural chemical properties that prevent bacteria and microbes from growing. Additionally, honey can kill off many types of bacteria due to its acidic pH level. When properly stored, honey’s unique composition and characteristics keep it from ever spoiling.
What Is Honey and Where Does It Come From?
Honey is a sweet, syrupy substance produced by honeybees from the nectar of flowers. Honeybees gather nectar from flowers and transport it back to their hive where it is transformed into honey through an amazing process.
The nectar collected by bees contains three key ingredients:
- Fructose – a simple sugar
- Glucose – another simple sugar
- Water
Back at the hive, honeybees ingest the nectar and regurgitate it multiple times until it is partially digested. The bees spread the nectar throughout the honeycombs in the hive, fanning it with their wings to speed up the evaporation process. This forces out much of the water, making the nectar thicker and more concentrated.
Enzymes are then added from glands in the bees’ heads to break down the complex sugars into simple sugars – fructose and glucose. After further evaporation, the end result is the thick, sweet, syrupy substance we know as honey.
Honey takes on varying flavors and colors depending on the types of flowers visited by the bees. For example, honey made from orange blossom nectar will taste much different than honey made from clover.
Honey’s Unique Chemical Properties
Honey contains special natural ingredients that give it unique flavor as well as antimicrobial and antibacterial properties. These natural chemicals make honey resistant to spoilage.
Sugar Content
Honey is comprised of 95-99% sugar content, mostly in the form of simple sugars fructose and glucose. This high sugar concentration creates a very low water content in honey. Microorganisms and enzymes need sufficient water to grow and spread. Therefore, the low moisture level in honey prevents organisms from growing and spoiling the honey.
Acidity
Honey has a relatively acidic pH between 3.2 and 4.5. This acidic environment is inhospitable to many bacteria and microorganisms that thrive in neutral pH environments around 7. The natural acidity inhibits microbial growth and protects honey from spoilage.
Hydrogen Peroxide
When an enzyme called glucose oxidase is added to honey by bees, the enzyme helps form small amounts of hydrogen peroxide in the honey. This hydrogen peroxide has mild anti-microbial effects and helps preserve honey.
Phytochemicals
Depending on the floral source that bees collect nectar from, honey can contain various phytochemical antioxidants and antibacterial compounds. Different varieties of honey have varying phytochemical profiles, but many types contain useful antibacterial phytochemicals.
For example, Manuka honey from New Zealand contains high levels of methylglyoxal which has anti-microbial effects.
Honey’s Effects on Bacteria
Given its natural chemical composition, honey can fight bacteria in several ways:
High Sugar Content
Drawing moisture out of microbial cells dehydrates and kills bacteria. Honey’s high sugar content creates a concentrated environment with very little moisture, which is unsuitable for bacteria.
Acidity
The acidic pH level of honey inhibits the growth of many pathogenic microorganisms which typically thrive in neutral pH environments. Bacteria cannot replicate easily in an acidic environment.
Hydrogen Peroxide
Hydrogen peroxide can have an anti-bacterial effect against some types of bacteria. The naturally occurring hydrogen peroxide in some types of honey contributes to the honey’s antibacterial properties.
Phytochemicals
Certain compounds naturally found in honey such as methylglyoxal have antibacterial and antimicrobial effects against dangerous bacteria including E. coli and salmonella.
Bee Defensins
Bees add an enzyme called glucose oxidase to honey, which produces gluconic acid and hydrogen peroxide from the sugars. This chemical reaction also produces bee defensins which are anti-microbial peptides that inhibit bacterial growth.
How Honey Stays Stable When Stored Properly
When sealed properly in an airtight container and stored away from heat, light and moisture, honey’s antibacterial properties and low water content keep it from ever spoiling.
Here’s why honey keeps almost indefinitely with proper storage:
Low Moisture
Water content is key to honey’s stability. When sealed properly, the low moisture level and concentrated sugar solution prevent microbial growth.
Acidity
Honey maintains its naturally acidic pH when sealed properly in storage. This acidity continues to inhibit bacterial growth.
Lack of Oxygen
When tightly sealed in an airtight container with no oxygen entering, aerobic microorganisms cannot grow. Anaerobic bacteria also cannot grow well due to honey’s low moisture.
Phytochemicals Stay Stable
Helpful antibacterial phytochemical compounds found in honey remain intact when honey is stored away from heat, light, and moisture. These helpful compounds continue preserving honey.
Enzyme Activity Halted
Enzymes that could break down and spoil honey become inactive when honey is stored sealed and away from heat. This prevents enzymatic reactions from changing honey’s flavor and composition.
Tips for Proper Honey Storage
Follow these guidelines for storing honey to maximize freshness and shelf life:
- Use air-tight containers with tight lids or seals. Mason jars work exceptionally well.
- Keep containers in cool, dark places like pantries or cupboards away from direct light and heat.
- Refrigeration can help extend shelf life, but is not required for most honeys if stored properly.
- Store honey jars upside down if possible. This keeps the honey saturated at the lid and minimizes any air exposure.
- Don’t store honey near hot appliances which produce heat, moisture or steam.
- Never store honey in the refrigerator door, which sees temperature fluctuations from frequent opening.
Follow those simple guidelines, and your honey should stay fresh for many years!
Signs that Honey Has Gone Bad
Despite its remarkable shelf life, honey can eventually go bad if not stored properly. Here are signs that honey may have spoiled:
- Change in texture – liquefying when crystallized honey should be solid, or crystallizing when liquid honey should be smooth. Changes in viscosity indicate decomposition.
- Change in color – darkening or lightening.
- Off odors – Honey should have a mild, sweet, floral smell. Foul odors indicate spoilage.
- Foaming or bubbling when shaken.
- Growth of mold, yeast or bacteria visible in the honey.
If you see any of those changes in your honey, it’s best to discard the honey rather than take a chance eating spoiled honey.
Does Honey Ever Actually Go Bad?
While honey has an extremely long shelf life, it can eventually spoil if not stored properly. Signs of spoiled honey include:
- Changes in texture and viscosity
- Discoloration
- Strange odors
- Foaming and bubbles
- Growth of mold, yeast or bacteria
These changes indicate that bacteria or fungi have been able to grow in the honey due to improper storage conditions.
So while honey may resist spoilage for many years, it does have a finite shelf life. Eventually the beneficial antibacterial properties honey contains can get overwhelmed if the honey is exposed to enough heat, light, air or moisture.
But when tightly sealed and stored in a cool, dry place away from light, honey seems to defy the laws of nature and remains edible for decades, if not centuries! Pretty amazing for a natural food product.
Frequently Asked Questions
Can honey last 3000 years?
It’s unlikely honey can last thousands of years without spoiling. However, honey has been found in ancient Egyptian tombs that was still edible after a few thousand years sealed in tombs. Given ideal storage conditions in sealed containers in dry tombs away from light and heat, honey can potentially last for thousands of years. But for most purposes, you can safely rely on honey staying fresh for several decades when properly stored.
Does honey go bad if it crystallizes?
No, crystallized honey has not gone bad. The sugars in honey can naturally crystallize by forming glucose crystals over time. This does not mean the honey is spoiled, it is still perfectly safe to eat. Crystallized honey can be liquified by placing the container in warm water and stirring. Some types of honey have a lower tendency to crystallize based on their sugar composition. Crystallization does not affect the safety or shelf life of honey.
Can you get food poisoning from bad honey?
Extremely unlikely, but possible in rare cases. Honey’s natural antibacterial properties prevent pathogenic bacteria that cause foodborne illness from growing. The biggest risk is infant botulism from Clostridium botulinum endospores, so children under 1 year should not eat honey. For adults, the natural properties of honey make foodborne illness very unlikely unless honey was produced under unsanitary conditions. Only eat honey from reputable local producers. Signs of spoiled honey will be obvious, at which point you should discard.
Does heating or freezing honey make it last longer?
Freezing crystallized honey can help prevent further crystallization during storage. However, freezing and thawing can degrade honey’s flavor. Heating honey to pasteurize it is not recommended, as excessive heat can destroy beneficial compounds in honey and negatively affect the flavor. Simply storing honey properly at room temperature keeps it fresh for many years without freezing or heating needed.
What is the best way to store honey long term?
The best way to store honey long term is in an airtight container like a mason jar or glass bottle with a tight lid. Store in a cool dark cupboard away from sources of light, heat and moisture. Keeping stored honey containers upside down helps keep honey saturated. Refrigeration can help extend shelf life but is not required. Following those simple guidelines, honey will stay fresh and edible for decades when stored at room temperature.
The Takeaway
Honey has a deserved reputation for having an extraordinarily long shelf life compared to other foods. When stored properly in an airtight container in a cool, dry environment, honey can remain fresh for many decades thanks to its unique antibacterial chemical properties including acidity, hydrogen peroxide content, phytochemicals, and low moisture. Its ability to kill or inhibit microbial growth allows honey to seemingly defy nature and avoid spoilage. While honey can eventually go bad if exposed to enough heat, light or moisture, following proper storage methods will keep your honey edible for a lifetime. So enjoy honey’s sweetness knowing it’s a food that truly lasts.
