We’ve all had a nearly-empty jar of mustard hanging out in our fridge for who knows how long. Whether you prefer Dijonhoney mustard, or spicy brown, there’s no end to the ways you can use this versatile condiment. Smear onto sandwichesstir into potato saladincorporate it into chicken dishesand add it as a secret ingredient in casseroles. But if you’re wondering if your mustard is still fresh—here’s how to know if it’s time to toss it, along with storage tips to make the most out of every jar.
Understanding Mustard Composition
Mustard is made by mixing yellow (white), brown, or black mustard seeds—or mustard powder—with water, vinegar, and other ingredients like salt, spices, herbs, sweeteners, and often preservatives. When the seeds are crushed and combined with liquid, natural enzymes create the compounds that give mustard its heat and sharp flavor. Vinegar helps preserve the mustard and keeps the flavor stable, but over time, the flavor of the mustard will fade and become more mild.
Shelf Life Of Mustard After Opening
Once opened, a container of mustard can last for about a year if properly stored. This is true for most varieties, including yellow, Dijon, spicy mustard, and honey mustard. If stored at room temperature, you may see signs of spoilage much more quickly.
If you’re wondering if you should adhere to the use-by date on the bottle, note that you can safely enjoy mustard past the use-by date if it is stored properly—as long as the mustard isn’t showing any signs of spoilage.
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Tips For Storing Opened Mustard
Mustard is a pretty stable condiment, so there are just a few key storage tips to keep it as fresh and flavorful as possible:
- Store tightly sealed: Store opened mustard in the refrigerator with the lid tightly sealed to prevent air and moisture from getting in.
- Clean the rim: Make sure to wipe the rim of the jar clean after each use for a tight seal.
- Opt for squeeze bottles when possible: Squeeze bottles are especially helpful—they limit air exposure and reduce the risk of contamination.
- Use clean utensils: Use clean utensils every time you dip into a jar of mustard in order to prevent the introduction of bacteria.
- Store in the fridge: While it’s important to keep mustard refrigerated, where you store it isn’t important. As opposed to eggs, milk, and many other types of condiments, it’s fine to store mustard in the fridge door where the temperature can be slightly warmer than the main body of the refrigerator.
Factors That Affect How Long Mustard Lasts
When it comes to how long mustard will stay fresh and flavorful, several factors can play a role:
- Vinegar and sugar content: Yellow mustard is typically the most stable thanks to its high vinegar content and lack of sweeteners. Dijon and whole grain varieties are slightly less stable, while sweetened mustards are more prone to spoilage.
- Exposure to heat and sunlight: Leaving mustard in a warm or sunny spot can speed up spoilage.
- Cross-contamination: Using utensils that have been dipped into other condiments (like mayo) can introduce new ingredients and bacteria, shortening the mustard’s shelf life.
- Preservatives: Store-bought mustards contain preservatives that extend their life, while homemade versions without additives should be used more quickly.
Signs of Mustard Spoilage
While it takes a long time for mustard to spoil in the refrigerator, if you do notice any of these signs, it’s best to discard to avoid the risk of foodborne illness:
- Mold: If there’s any noticeable mold around the rim or inside the jar, discard immediately.
- Off-smell: A sour or rancid odor is a sign that the mustard shouldn’t be used.
- Texture changes: If the mustard becomes watery or overly separated and won’t emulsify properly, toss it out.
- Flavor loss: If it just doesn’t taste right, err on the side of caution and discard.
Now that you know how to properly store your mustard, you can go ahead and start using it in some of our favorite recipes.