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How Can You Tell If Oatmeal Has Gone Bad Using A Surefire Method?

In this article I’ll tell you how to use your senses to identify oatmeal that is past being safe to eat, and what you can do to keep it staying fresh longer.

whole oat groats

When I was a child, my mother always cooked rolled oats on winter mornings. It was great, warm nourishment for us kids before we set off for school, and for my dad when he came up from the barn from having milked the cows.

I still love a warm bowl of oatmeal, and I have to confess, after stirring in some milk, along with some cinnamon, I like to sprinkle lots of brown sugar on the top. Maple syrup is another great topping. But I digress.

Oatmeal is an inexpensive, healthy, and enormously versatile food. To understand how to store it effectively, it helps to know about different kinds of oats.

What Are The Different Kinds Of Oats?

The oat, in its more natural, least processed form, is called whole oat groats. With groats, the whole oat grain is intact, and only the hull is taken off. It’s fairly hard and therefore takes a while to cook and soften.

Steel-cut oats are another form of oats which have enjoyed great popularity in recent years. Steel-cut oats are simply oat groats that are cut up into smaller pieces. They look like pellets.

This is achieved by slicing the groat with a steel blade, hence the name. Due to their smaller size, steel-cut oats cook faster than oat groats.

Both groats and steel-cut oats are very healthy options as there is little to no processing.

Any Outlander fans out there? There are numerous references in Diana Gabaldon’s books, the earlier ones at least, to “parrich”. We call it porridge, but likely Jamie and Claire’s oatmeal looked and tasted a little different than our oatmeal of today.

There is a type of oat called Scottish oats. Scottish oats are made from ground oat groats.

In North America, we are most familiar with rolled oats. As its name implies, the oats are rolled, but not until they have first been steamed which softens the oat groat and enables the oats to be rolled.

Rolled oats are sometimes referred to as old-fashioned oats. They are perhaps the most versatile of all of the oat varieties.

Since they are rolled quite flat, they cook much more quickly than either whole oat groats or steel cut oats.

There are a few varieties of rolled oats. In addition to the standard old-fashioned rolled oats, there are also quick oats and instant oats. Both quick oats and instant oats are processed a little more than old-fashioned oats.

Quick oats undergo an additional rolling, making them flatter and thinner. Instant oats, in addition to being steamed and rolled, are actually pre-cooked. This makes instant oats the fastest to cook. 

As the oat is increasingly processed, its texture when cooked becomes softer, so by the time you get to instant oats, they take little time to cook, and have a somewhat mushy consistency.

What Are The Different Kinds Of Oats?

Here is a handy table which allows you to see, at a glance, the various types of oats and some of their characteristics.

RELATED: Oats Side Effects (Is It Good To Eat Oatmeal Every Day?)

Quick Table: Different Types Of Oats

Type Of OatHow It Is ProcessedUses OfHow Long To Cook on Stove Or Microwave
Oat GroatsHull is removedCooked cereal, cookies, squares, biscuits, risotto30-45 Minutes On Stove
Steel-Cut OatsHull is removed, groat is sliced into small piecesCooked cereal, overnight oatmeal, cookies, muffins, savory oatmeal with lentils20-30 Minutes On Stove
Scottish OatsGroats are groundTraditional porridge, rolls, scones, savory oats with vegetables, and an egg.12-15 Minutes On Stove
Rolled Oats Also Called Old-FashionedGroats are steamed then rolledOatmeal, cookies, bread, muffins, pancakes, squares, meatloaf, hamburgers5-10 Minutes On Stove
Quick OatsGroats are steamed and rolled thinOatmeal, muffins, pancakes, bars, granola.3 Minutes On StoveIn Microwave – 2 Minutes
Instant OatsGroats are steamed, rolled and pre-cookedOatmeal, muffins, cookiesRolled & quick oats preferred for baking as instant are too mushy.Microwave for 60-75 seconds OR pour boiling water on oats and let stand for 2 Minutes

From a nutrition perspective, all types of oats are complex carbohydrates, and have nutritional value. However, whole groats and steel-cut oats have the most fiber. This is because they are processed the least.

Eating a breakfast that is high in fiber can help to keep you full longer, and can be helpful to those people who are trying to reach or maintain a healthy weight.

Oats can also help to lower bad cholesterol levels, decrease inflammation, and help with immune function. They play a role in keeping the brain and the heart healthy, and are good for our gut health.

What Are The Signs That Oatmeal Has Gone Bad?

Oats possess many vitamins and minerals: iron, thiamin, zinc, magnesium, and selenium. Oats have few calories (There are only 110 in a serving of quick oats.) and they pack antioxidants, too!

This simple, inexpensive powerhouse that lends itself to many recipes, is also easy to store and can last for a long time.

So now that we know about the different kinds of oats available, and how good they are for us, let’s talk about the signs that those oats might be going bad.

What Are The Signs That Oatmeal Has Gone Bad?

Oats typically have a long shelf life, but like all foods, they can eventually go bad. Here I outline for you what signs to look for that indicate you should probably not eat the oats.

You don’t need any fancy equipment to test your oats, you just need to use your senses, the sense of sight, the sense of smell and the sense of taste.

Sense Of Sight

We’ll begin with the sense of sight. Open the container of oats and take a good look at them. Is there something off in their color? When you first bought the oats, they would have been a cream color or a light brown.

If your oats have a different color, check for mold. If the oats show signs of mold, you will want to throw them out.

Mold will spread quickly throughout the oats, so don’t trust any of them once you see even a spot of mold. It’s time to toss the whole lot.

Oats may also clump – this is another sign that they are no longer good.

Sense Of Smell

Using your nose is another great way to check whether or not your oats are still okay to eat. Healthy oats will smell a little bit nutty. When oats have gone bad you will detect an unpleasant sour scent.

If your oats smell that way, don’t power through cooking them and eating them. It won’t be an enjoyable experience.

Sense Of Taste

Perhaps you didn’t detect any discoloration or even an off scent on your oats before you cooked them, but when you had that first spoonful, it wasn’t the yummy taste you were expecting.

In fact, they tasted bitter and a little funky. Stop there, and toss the oats.

Oats that are good will taste nutty and sweet, not sour.

What Are The Things That Make Oats Go Bad?

There are certain culprits that will turn oats bad, and can decrease that typically long shelf life. They are oxygen, moisture, and pests.

1. Oxygen

Oxygen is not the friend of a lot of foods. In the case of oats, exposure to oxygen kills all those great nutrients that make oats so healthy for us. 

2. Moisture

I live in a part of the world where there is significant humidity during summer months. Humidity is an enemy of dry goods because it messes with the whole dry aspect.

Humidity will cause your oats to grow mold, and once mold begins to form it will spread throughout the oats quickly.

3. Pests

Oats, if around for a very long time, can become the home of pests like weevils or pantry moths. Mice will also chew through bags and get into oats.

RELATED: Can You Eat Oatmeal on Keto?

How Do You Discourage Oatmeal From Going Bad?

We’ve identified the enemies of oats. Now we’ll look at what can be done to avoid these things, and keep our oats healthy and around for a long time.

Oats can be kept free of pests, mold and maintain their nutritional value through proper storage. This means not only finding the right spot to keep your oats, but also using the right container to store them in.

Frequently Asked Questions

Where Should Oats Be Stored?

Oats should be stored in a dry, cool, dark place. You might think your basement would work. Basements are typically dark and cool. They are, however, often damp.

Dampness will cause mold to grow, and in a damp environment, oats will take on smells. Most of us don’t want to eat oats that taste like our basement.

The best places for oats to be stored are in a cupboard or pantry, in the fridge or in the freezer. Most often people store oats in a cupboard or pantry as we usually want to keep our freezer and fridge space for foods that really need to be there.

What Should Oats Be Stored In?

The best container to store your oats in partly depends on how often you will use them. If you are going to be using the oats frequently then it is fine to keep them in the bag they came in. 

If you are concerned about rodents, you may want to put the bag in a plastic, glass or ceramic container.

I live in the country and deal with mice getting into my house every fall. I keep all of my pantry items in jars or heavy-duty plastic containers.

If the oats will not be used often, you will want to put them in an airtight container.

Heavy-duty plastic containers with tight-fitting lids, or ceramic containers with a tight lid and seal, or a glass jar with a tight-fitting lid are all good options.

Once you have put your oats in the right container, you may safely store them for up to 2 years depending on the type of oats.

What Should Oats Be Stored In?

How Long Will Oats Stay Good?

The type of oat determines how long you can count on your oats staying good. The less processed the oat, the longer shelf life it will have.

Whole oat groats, which have only the hull removed, and steel-cut oats that are similar to whole groats, only cut into smaller pieces, will stay good the longest.

They are only minimally processed, and you can expect them to be good for up to two years.

Rolled oats and quick oats, which through steaming and rolling are more processed, have a shorter shelf life. These types of oats will generally be good for 1-2 years. 

Instant oats, which have been processed more than rolled and quick oats, have the shortest shelf life. They should be good if used within 1-2 years.

Should Oatmeal Be Thrown Out If It’s Beyond The Best Before Date?

Best before dates are guidelines, not absolutes. Having said that, if your oats are past the date on the package, be sure to examine them closely using the sensory tests explained earlier in this article.

Are the oats a healthy cream or light brown color? Do they smell and taste slightly sweet and nutty? If so, they are safe to use.

What Can You Do With Oats Once They Are Showing Signs Of Being Past Their Best?

Oatmeal is really extraordinary. Even once it’s past being good for eating, there are other purposes for it. So don’t just pitch it in the garbage.

Here are some ideas that you might like to try.

  1. Sprinkle some in your bath to relieve dry, itchy skin.
  2. Make a face mask to help with acne-prone skin.
  3. Mix it with water and let it sit on your hair to reduce split ends and sooth a dry, itchy scalp.
  4. Bathe your pets in it. It’ll help decrease odor.
Jess Smith