Cornstarch, also known as cornflour in some regions, is a fine, powdery substance derived from the endosperm of corn kernels. It is commonly used for thickening sauces, gravies, and soups and for creating a crispy coating on fried foods. But does cornstarch go bad?
The simple answer is that cornstarch does not spoil in the same way dairy or meat does, but its effectiveness as a thickening agent can diminish over time.
This article explains the shelf life of cornstarch, how to keep it fresh for longer, and various substitutes to try. You’ll also learn about how to make gravy with cornstarch.
How long does cornstarch last before going bad?
Regarding the shelf life of cornstarch, the good news is that it’s incredibly long-lasting. Typically, cornstarch can last indefinitely. However, for best results in recipes, it’s recommended to use opened cornstarch within 2 – 3 years. This time frame isn’t a strict expiration date but a guideline for optimal quality.
It’s also important to store cornstarch properly, as exposure to moisture can cause it to develop mold or a musty smell, making it unfit for consumption.
How to tell if your cornstarch has gone bad
While cornstarch has a very long shelf life, certain signs can indicate it’s time to replace your supply:
Check for discoloration
Fresh cornstarch is a fine, white powder. If you notice any discoloration, such as yellowing, gray spots, or visible mold growth, it’s a sign that it’s gone bad.
It’s clumpy
Cornstarch should have a light, powdery texture. If it feels lumpy or hard, it has likely absorbed moisture. While you can try to break these clumps apart and sift the cornstarch, its effectiveness as a thickening agent might be reduced.
Foul odor
Cornstarch should have a neutral smell. Any off or unusual odors indicate that it has been compromised. This could be due to exposure to other strong-smelling foods or bacterial growth.
Pest infestation
Sometimes, pantry pests like weevils can infest cornstarch if not stored properly. If you see any bugs in the container, it’s best to discard the entire amount.
Storage tips
Proper storage of cornstarch is relatively straightforward. Here are some best practices to ensure your starch stays in prime condition:
- Use an airtight container: Once you open a package of cornstarch, transferring it to a dry airtight container is advisable. This protects it from moisture, air, pests, and contaminants.
- Store in a cool, dry place: Cornstarch thrives in cool and dry conditions. A pantry or a cupboard away from heat sources like stoves or radiators is ideal. Avoid areas with significant temperature fluctuations, such as near a dishwasher or refrigerator.
- Keep away from strong odors: Cornstarch can absorb strong odors, which could affect its taste and the flavor of your dishes. Store it away from foods with strong odors or any chemicals.
Cornstarch alternatives: What can I use instead ?
Sometimes, you might find yourself in the middle of cooking, only to realize your favourite starch is past its prime or you’ve run out. Fortunately, several alternatives can save your dish:
- Flour: Regular all-purpose flour is a common substitute. Use twice the amount of flour for the cornstarch called for in a recipe. Keep in mind that flour needs a bit longer to cook and can give a slightly cloudy appearance to your sauces or gravies.
- Arrowroot powder: This is an excellent gluten-free alternative with a similar texture and thickening power. Use it in a 1:1 ratio.
- Tapioca starch: Extracted from cassava roots, tapioca starch is another gluten-free option, especially for thickening acidic liquids. Use in a 1:1 ratio.
- Potato starch: This substitute works best in baking and for thickening sauces. Use it in a 1:1 ratio, but add it towards the end of cooking, as prolonged heat can reduce its thickening abilities.
- Rice flour: Perfect for frying, rice flour can be used as a substitute. It’s also gluten-free. Use a bit more rice flour to achieve the same effect.
- Ground flaxseeds: When mixed with water, ground flaxseeds can be a nutritious thickener, though they add a slightly nutty flavor.
- Xanthan gum: This option is gluten-free and perfect for thickening gravies and sauces. Use about 1/4 teaspoon of xanthan gum for one tablespoon of cornstarch.
How to make cornstarch gravy
For those with gluten sensitivity, cornstarch offers an excellent alternative to flour in gravies. Moreover, it ensures a smoother texture, as it doesn’t clump as easily as flour. Here’s how to make gravy with cornstarch:
Ingredients
- 2 cups of broth (chicken, beef, or vegetable)
- Two tablespoons of cornstarch
- Cold water
- Salt and pepper, to taste
- Optional: drippings from cooked meat, herbs, or additional seasonings.
Directions
- In a small bowl, mix two tablespoons of cornstarch with an equal amount of cold water to create a slurry. Ensure it’s thoroughly mixed and smooth.
- Pour the broth (with or without meat drippings) into a saucepan and bring to a gentle simmer over medium heat.
- Slowly add the slurry to the simmering broth. Keep stirring to prevent lumps from forming.
- Continue to simmer and whisk the gravy for a few minutes until it thickens to your desired consistency. The gravy will thicken further upon cooling.
- Taste your gravy and add salt, pepper, and any additional seasonings or herbs to suit your taste.
- Once the gravy reaches the perfect thickness and flavor, remove it from heat and serve it hot over your dish.
Frequently asked questions
Is it OK to use expired cornstarch?
Cornstarch can be used past its expiration date if stored properly. However, it’s crucial to check for signs of spoilage, like changes in color, smell, texture, or mold. If it passes these checks, it is safe to use.
What can I do with old cornstarch?
Old or expired cornstarch can be used for cleaning (as a grease absorber on fabrics), polishing silver, deodorizing shoes, or even DIY crafts (like homemade paint or playdough).
Final thoughts: So, does cornstarch go bad?
Cornstarch, like baking soda, has a shelf life but is pretty long. If kept in a cool, dry place and sealed properly, they can last indefinitely. However, for best results, it’s recommended to use it within a couple of years.
