Cornstarch is a pantry staple known for its longevity, but like all food items, it can go bad under certain conditions. Here’s a detailed look at whether cornstarch goes bad, how to tell if it has spoiled, and how to store it properly to extend its shelf life.
Shelf Life
Indefinite Shelf Life
Longevity: Cornstarch can last indefinitely if stored properly. It does not spoil in the traditional sense because it lacks moisture, which is necessary for bacterial growth and mold.
Best By Dates: The “best by” date on cornstarch packaging is more about peak quality rather than safety. It can still be used effectively after this date if it has been stored correctly.
Proper Storage
Ideal Storage Conditions
Cool, Dry Place: Store cornstarch in a cool, dry place away from moisture and heat sources. The pantry is usually the best place.
Airtight Containers: Keep cornstarch in its original container with the lid tightly sealed, or transfer it to an airtight container to prevent moisture and contaminants from getting in.
Avoid Freezing or Refrigeration
No Freezing or Refrigeration: Do not store cornstarch in the freezer or refrigerator, as the moisture in these environments can cause it to clump and spoil.
Signs of Spoilage
Moisture Exposure
Lumps: If cornstarch has formed lumps, it means moisture has gotten into the container. While lumps alone don’t necessarily mean it’s spoiled, they indicate that it’s on its way to going bad.
Mold: The presence of mold is a clear sign that cornstarch has gone bad. Mould can appear as gray or green spots and should be discarded immediately to avoid health risks.
Smell and Appearance
Bad Smell: Cornstarch should have a neutral, slightly corn-like smell. If it smells sour or strange, it’s best to throw it away.
Bugs/Insects: If you see tiny black or brown bugs, it means the cornstarch has been infested and should be thrown away.
Is Expired Cornstarch OK to Use?
Yes, expired cornstarch is generally safe to use as long as it has been stored properly and shows no signs of spoilage. Cornstarch does not spoil in the traditional sense because it lacks moisture, which is necessary for bacterial growth and mold. Here are some important things to keep in mind:
Storage Conditions: If cornstarch is kept in a cool, dry place and in an airtight container, it can last indefinitely.
Signs of Spoilage: Before using expired cornstarch, check for any signs of spoilage such as lumps, a bad smell, discoloration, or the presence of bugs. If it remains a fine, white powder with no off odors, it is safe to use.
Effectiveness: While cornstarch remains safe to use, its thickening power might diminish slightly over a very long period. However, this is generally not a significant concern.
Can Bacteria Grow in Cornstarch?
Bacteria generally do not grow in cornstarch under normal storage conditions because it is a dry, fine powder. However, if cornstarch becomes moist, it can create an environment conducive to bacterial growth. Here are some considerations:
Moisture Exposure: Moisture is the primary factor that can lead to bacterial growth in cornstarch. Keeping cornstarch dry is crucial to prevent this.
Skin Use: When used on the skin, cornstarch can attract bacteria if it becomes moist, potentially leading to skin issues like pimples or rashes.
Does Cornstarch Lose Its Thickening Power?
Cornstarch can lose its thickening power under certain conditions, such as prolonged exposure to heat or acidic environments. Here are some details:
Heat and Agitation: Overcooking or continuous stirring can break down the starch molecules, causing the thickened mixture to thin out again.
Acidic Ingredients: Cornstarch is less effective as a thickener in highly acidic environments. In such cases, alternatives like arrowroot or tapioca starch may be more effective.
Storage Duration: Over an extended period, cornstarch may gradually lose some of its thickening power, but this process is slow and generally not significant enough to impact most culinary uses.
Conclusion
Cornstarch can last a very long time if stored correctly in a cool, dry place. While it doesn’t spoil like other foods, moisture can cause it to form lumps, mold, or attract pests. Always check for a bad smell, mold, or bugs before using old cornstarch. Proper storage keeps your cornstarch effective and safe to use for years.
Also read: How to Make Hot Honey: A Step-by-Step Guide
