Simple syrup is a common ingredient used in cocktails and baked goods. It’s made by combining equal parts sugar and water and heating until the sugar dissolves. But with its high sugar content, simple syrup can go bad over time. Here are some signs to look for to know if your simple syrup has spoiled and is no longer safe to consume.
What is simple syrup?
Simple syrup is a liquid sweetener made from equal parts granulated sugar and water. The two ingredients are combined in a saucepan and heated, stirring frequently, until the sugar fully dissolves. Once cooled, the syrup has a smooth, viscous consistency and can be used as a sweetener for drinks, desserts, and more.
The typical ratio for simple syrup is 1:1, meaning one cup of sugar dissolved in one cup of water. However, it can be adjusted to change the sweetness. A 2:1 ratio (two cups sugar to one cup water) makes a richer syrup. Likewise, more diluted syrups can be created with ratios like 1:2 (one cup sugar to two cups water).
Common uses for simple syrup
- Sweetening iced coffee, tea, and cocktails
- Adding sweetness to smoothies or milkshakes
- Making dessert sauces and toppings
- Sweetening whipped cream
- Baking in place of granulated sugar
How long does simple syrup last?
The shelf life of simple syrup depends primarily on how it is stored. General guidelines are:
- Refrigerated – 2 to 3 weeks
- At room temperature – 1 to 2 weeks
- Frozen – Several months
Simple syrup contains no preservatives. Over time, the water in the syrup can lead to the growth of mold, bacteria, and yeast. Refrigeration helps slow this down. The freezer extends shelf life even further by stopping microbial growth.
Maximizing freshness
Follow these tips to keep simple syrup fresher for longer:
- Store in an airtight container like a mason jar or squeeze bottle.
- Refrigerate after opening.
- Keep water mixture boiling for 5+ minutes to sanitize.
- Use bottled or boiled water rather than tap.
- Add a splash of vodka or other neutral spirit as a preservative.
Signs your simple syrup has gone bad
Watch for these indicators that simple syrup is past its prime and needs to be discarded:
Appearance changes
- Crystal formation – Sugar crystals or grainy texture means the syrup was not sufficiently dissolved and heated.
- Cloudiness – A syrup that is no longer clear could indicate microbial growth.
- Mold – Spotting any fuzzy mold is a sure sign of spoilage.
- Color darkening – Over time, the color may shift from clear or pale yellow to a darker amber shade.
Texture changes
- Thin, watery consistency – A simple syrup that appears diluted or is noticeably less viscous has likely been contaminated.
- Thick, glue-like texture – Evaporation over time can cause the syrup to become abnormally thick.
Smells
- Fermented odor – A beer-like, yeasty, or vinegary smell indicates fermentation.
- Rotten smell – An particularly unpleasant or rotten stench is a giveaway that it has spoiled.
- Moldy odor – A musty, earthy aroma may accompany visible mold growth.
Taste
- Loss of sweetness – If the syrup is noticeably less sweet, sugars have broken down.
- Sharp, bitter flavor – Fermented simple syrup takes on unpalatable acidic, vinegary notes.
- Off tastes – Any clearly unpleasant flavors like sourness, mustiness, or rottenness mean toss it.
What causes simple syrup to go bad?
There are a few common causes behind simple syrup going bad and developing signs of spoilage:
Microbial contamination
The combination of sugar and water in simple syrup provides an ideal breeding ground for unwanted microorganisms like mold, yeast, and bacteria. If introduced via tap water, utensils, or storage containers, they can multiply and lead to faster spoilage.
Improper storage
Leaving simple syrup out at room temperature encourages rapid growth of bacteria and mold. Failing to store in an airtight container also introduces contamination risks.
Sugar recrystallization
If the syrup is not heated to sufficiently dissolve the sugar initially, crystals can begin to reform during storage as moisture evaporates.
Natural chemical changes
Over many weeks, simple syrup’s sucrose molecules naturally break down into glucose and fructose. This affects sweetness, texture, and flavor.
How to tell if bad simple syrup is safe to consume
It’s best to avoid consuming simple syrup that shows any signs of spoilage. Mold growth in particular makes it very unsafe for consumption. However, with syrups that just show minor darkening or thickening, look for the following signs it may still be safe to consume:
- No visible mold growth
- No sour, bitter, or otherwise unpleasant taste
- No separation of liquid and sugars
- No crystallization in texture
- No odd smells apart from slight darkening
When in doubt, it’s recommended to throw it out. The potential risks of foodborne illness outweigh enjoying a questionable batch of simple syrup.
How to store simple syrup properly
Follow these simple syrup storage tips to help maximize its shelf life and freshness:
Use sterilized containers
Pour hot simple syrup into containers like squeezable bottles, mason jars, or cruets that have been sterilized with boiling water or run through the dishwasher.
Refrigerate after opening
Keep freshly made simple syrup sealed at room temperature for up to 1 week. Once opened, move to the refrigerator.
Store airtight
Minimize air exposure by using bottles or jars with tight lids or caps. Oxygen can encourage mold growth.
Keep frozen for long term
Simple syrup can be frozen for 3 to 4 months. Thaw in the refrigerator before using.
Add preservatives (optional)
A splash of vodka or other spirits helps inhibit microbial growth. Citric acid or potassium sorbate are other preservative options.
Can you rescue a bad batch of simple syrup?
If your simple syrup develops some undesirable qualities like sugar recrystallization or darkening but is still salvageable, try these troubleshooting techniques:
Reheat and strain
Gently rewarming the syrup may help dissolve sugar crystals. Strain while warm through a cheesecloth to remove impurities.
Dilute and boil
For syrups that have become too thick, add small amounts of water to thin out consistency. Boil for 3-5 minutes.
Refresh with new syrup
Combining a small amount of the old syrup into freshly made simple syrup can help mask off flavors.
Store in the fridge
Refrigeration can slow further deterioration. But if any mold, bitterness, or acidity is detected, it’s best to discard.
Frequently Asked Questions
Can you get sick from bad simple syrup?
Consuming simple syrup contaminated with potentially harmful bacteria or mold can certainly cause illness. Look for signs like vomiting, diarrhea, fever, or fatigue. Discard any syrup with off smells, tastes, or appearance.
Does simple syrup need to be refrigerated?
Refrigeration extends the shelf life of opened simple syrup to 2-3 weeks. Unopened, it can be kept at room temperature for up to 1-2 weeks. For maximum freshness, refrigerate after opening.
Can you reuse simple syrup?
Leftover simple syrup can be reused, provided it has been properly stored and shows no signs of spoilage. Reheating and straining is recommended before reuse. Discard any syrup that smells, tastes, or looks abnormal.
Does simple syrup freeze well?
Simple syrup freezes nicely for long-term storage. It prevents microbial growth. Thaw frozen syrup in the refrigerator before using. Shake or stir gently to recombine any separated liquid and sugars.
Is crystallized simple syrup safe to use?
If sugar crystals have formed in simple syrup, it is still safe to consume. However, the texture may be gritty or grainy. Reheating gently should dissolve the crystals. Or strain through a cheesecloth before using.
Conclusion
With its high sugar content, simple syrup can go bad eventually. But following proper storage methods like refrigeration, airtight containers, and freezing extends its shelf life significantly. If any mold, crystallization, off smells or tastes develop, it’s best to discard. But looking for signs like a smooth consistency and lack of bitterness can indicate a batch is still safe to consume or rescue.
