How Long Do Overnight Oats Last?

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Looking for an easy meal prep to make a healthy breakfast option? Overnight oats are a classic go-to for a ready-made meal on the run.

Grab a jar of soaked oatmeal from the fridge. Then, you eliminate the worry about cooking a healthy and fulfilling breakfast.

So, how long do overnight oats last? When stored in an airtight container in the fridge, overnight oats will last for up to five days. This makes them great for meal prep. Freezing overnight oats also works if you want to prepare the no-cook oatmeal a few months in advance. Leaving overnight oats at room temperature is not recommended.

This article covers the ins and outs of storing overnight oats, how to make no-cook oatmeal last longer, and how you can maintain the oatmeal texture when they are soaked ahead of time.

What Are Overnight Oats?

Overnight oats are a healthy, wholesome, and fulfilling meal that is prepared without cooking. Overnight oats are extremely versatile and can be made with countless variations. Therefore, you can eat them 7 days in a row without getting bored.

In addition to the flavorful combinations, whole-grain oats offer considerable nutritional value and health benefits.

Oats contain 5 grams of protein and 3 grams of dietary fiber per half-cup serving. This is one of the reasons they have become a good breakfast to get the day started.

Oats are rich in antioxidants, and beta-glucan fiber, and also contain trace amounts of essential vitamins and minerals

The high fiber content keeps your hunger at bay for much longer lengths of time. The satiated feeling is one of the reasons overnight oats are good for weight loss.

As an added bonus, whole grain oats can lower cholesterol levels, lower blood sugar levels, relieve constipation, and promote heart health. No wonder this superfood has timeless success being a part of a healthy diet.

Breakfast Option

If overnight oats are so healthy, why aren’t more people eating them for breakfast? Overnight oats are about convenience.

The meal prep is completely effortless and the no-cook meals take less than 5 minutes to make.

Place the ingredients in a jar, give a quick stir, and seal the lid. Then, place in the fridge to soak for 12 hours. That’s it! Your tasty and healthy meal prep is ready to eat with no cooking required!

Base flavor combinations of the soaked oats can be varied with different milk, dairy-free alternatives, juice and even water.

Enhance the foundation of the flavor profiles and textures with oatmeal toppings. There is no possible way to run out of exciting overnight oatmeal collaborations.

Try adding fresh or dried fruits, nuts, seeds, and syrups to your overnight oats.

From banana yogurt overnight oats to blueberry lemon overnight oats, there are endless options and combinations for you to explore.

Storage Guide

If you want to incorporate overnight oats into your diet, then learn how to store the no-cook oatmeal.

Improperly keeping overnight oats can have an effect on the quality, shelf life, and overall preservation. So, do you keep overnight oats at room temperature, refrigerator or freezer?

Let’s discuss the best storage options and how to extend the freshness of your overnight oats.

Can You Make Overnight Oats Without Refrigeration?

Nuts, seeds, and oatmeal are kept at room temperature in a cool, dark, and dry storage area.

Leaving overnight oats without refrigeration is a potential food safety hazard that should be avoided.

When mixed with water, oats are a perishable food that will become the breeding ground for a host of microorganisms. According to the food safety guidelines provided by the USDA, overnight oats can be kept at room temperature for up to 4 hours.

Under the right conditions, you can store dry oatmeal for up to 30 years. However, once liquid is added and the oats are kept at room temperature, microscopic organisms start growing very quickly.

Do Overnight Oats Go Bad?

When making a few portions of overnight oats at the same time, it is easy to lose track of. That is why it is a good idea to become familiar with the signs that overnight oats have gone bad.

Even though overnight oats typically stay fresh in the fridge for up to 5 days, you should always check the quality and freshness. It is important to see if the oatmeal has gone bad before diving in for a spoonful.

Things to look for that signal the oatmeal has gone bad:

Discoloration: Oatmeal is a pale or light cream color. If unusual dark spots show up inside the mixture, then it’s not worth risking your health by eating the unknown.
Mold: Mold growth would be one of the major culprits of overnight oats. White or green mold commonly grows on the surface, discard them immediately.
Off-putting smell: A quick sniff test will largely determine whether or no the overnight oats are still fresh. If the smell is off, then don’t eat the soaked oats.

How to Store Overnight Oats in the Fridge

To store overnight oats in the fridge to maintain the best qualities and texture, follow a few simple rules.

Choose The Best Container

Storing the oats in the right container is important, here are the best overnight oats containers.

As a general rule, airtight containers tend to maintain freshness for longer periods of time.

Glass is preferred over plastic. Glass does not retain bad odors or funky flavors inside the walls of the material. However, plastic absorbs the smells from past meals.

Jars with a tightly sealed lid work best for storing overnight oats. For storing overnight oats, wide-mouth, 16-ounce mason jars are our favorite containers.

When served in a clear glass jar, the meal prep looks appealing. This is just another reason that you will be excited to eat a healthy and nutritious breakfast. Looks can be just as important as the smell and taste of the dish.

Store With or Without Toppings

There are mixed options on this matter.

No matter how you put it, oatmeal has a somewhat mushy texture, after all, it is a porridge. So, adding toppings to overnight oats will inherently add the the softness and sogginess of the meal prep.

When preparing overnight oats, you have two options: add the toppings before or after refrigeration.

Add Toppings Before Refrigeration

The first and most obvious observation is that the toppings will change in texture and become mushy and soggy. However, these are facets that can be enjoyed as an appealing taste.

Fruits and nuts will soften when storing overnight oats in the fridge. The flavors really meld together and the complexity of the dish can be tasted in each bite.

Overnight oats can be made with cooked, fresh, or frozen berries and fruits.

Fresh fruits like blueberries, pineapple, mango, and strawberries tend to hold their shape better than softer blackberries, kiwi, and raspberries.

Frozen fruits turn into a jammy texture that bleeds flavor to the surrounding oats. Frozen berries are a favorite overnight oats topping. This enhancement is hard to resist since oats have a mild and bland flavor all by themself.

Overnight oats with fruits like apple and banana will oxidize and turn light brown. However, the soaked-in flavors will enhance the taste and there will be no texture impact to the no-cook oatmeal.

If you are eating the oats the next day, and you want the meal prep to be completely finished, then it is encouraged to add the fruits, nuts, and seeds to the mixture so that the entire meal prep is ready to eat.

Add Toppings After Refrigeration

There is a drastic difference between adding overnight oats toppings before and after refrigeration.

Of course, the mix-ins placed on top after soaking the oats are going to have a texture that will be largely unchanged. However, you will be missing out on the flavors that are absorbed into the oats making them taste more complex and magically delicious.

We love to mix in fruits, nuts, and seeds before refrigerating to layer the flavor with a twist of complexity, and also add oatmeal toppings after refrigerating for freshness and undeniable crunchiness.

How Long Do Overnight Oats Last in the Fridge?

When stored in the fridge, overnight oats will last for up to 5 days.

The taste and texture will be at the peak of freshness on the first day. However, overnight oats will remain safe for consumption for about 5 days in the fridge.

The concern over freshness primarily falls on the expiration date of the mix-in ingredients you are using to make the overnight oats. If the products you are using, say the milk or yogurt, expire sooner, then just the shelf life of the overnight oats accordingly.

When it comes time to serve the oats, remove the container from the fridge and give it a good stir. The liquid tends to separate from the oats when stored in the fridge.

Stirring the oats will combine the ingredients and bring the mixture back together.

Furthermore, it will result in a better texture since the oats at the bottom will be much softer than the crunchy oats on the top layer. Stirring will blend the consistency of the porridge and add little bits of crunch throughout the mixture.

Occasionally the liquid ratio is off based on the absorption rate of the oats or mix-ins like flaxseeds and chia seeds. If you feel like there is not enough liquid when stirring the soaked oats, then now is a perfect opportunity to add a splash of liquid or a spoonful of yogurt.

Where to Put in the Fridge

If you are stacking up a week’s worth of overnight oats, the last thing you want to risk is having all your hard work spoiled by improper placement. The no-cook oatmeal has gone bad.

Especially when storing overnight oats prepared with milk or yogurt, you want to be diligent about where the containers are placed for the next 5 days.

Don’t put the oats on the fridge door. The temperature fluctuates when the refrigerator door is opened and closed, therefore it is slightly higher and the oats, especially when made with milk, will have a higher chance of spoiling.

To keep your overnight oats safe, store them in plain view in the middle of the refrigerator. You don’t want to lose sight of the delicious meal prep and potentially forget that they are even there!

Tips for Storing

Understanding a few basic tips for storing overnight oats will extend the shelf life, improve the taste, and make your job even easier. Make the best of your healthy meal by storing overnight oats the right way.

By the way, we have a complete guide for how to store oatmeal too.

Use Almond Milk

Overnight oats made with water have to stay fresh longer than oatmeal made with milk. But, what if you prefer oats with milk?

Almond milk is a great dairy-free alternative to using milk to make overnight oats. In fact, the shelf life of almond milk is a few days longer than cow’s milk. So it will help to extend the freshness by that much more.

Almond milk is compared to the thickness and creaminess of cow’s milk. Additionally, use it to make vegan overnight oats.

Can You Store Overnight Oats in the Freezer?

If you want the overnight oats to last for longer than 5 days, you can store them in the freezer.

In general, you can freeze overnight oats to last up to 6 months. Recognize that taste, texture, and quality can affect how long they are frozen.

Store overnight oats in the freezer in a freezer-safe airtight container.

If you feel like the oats are dry and need a bit more liquid, simply add water, juice, or milk to make a creamier oatmeal.

Meal Prep Overnight Oats

Overnight oats can last for up to 5 days in the fridge.

If you prefer them chewy, slightly decrease the amount of liquid and reduce shelf life to 2 days. You can always add a splash of liquid to adjust the ratio when serving.

So how can you have chewy overnight oatmeal ready to eat seven days a week? Here’s the best way to meal prep overnight oats:

Start by preparing two jars of overnight oats (two servings).
Once you finish eating the 1st portion, replenish by putting a new jar of oats in the refrigerator.
- Combine 1 part of oats with 1½ parts of water, juice, or milk, add mix-ins if you prefer, and refrigerate.

Add Enough Liquid to Overnight Oats

No cook oats absorb the liquid while soaking overnight and are ready to be eaten the very next day. The oats soak up in about 4 hours. However, it is recommended that the mixture sits for at least 12 hours before consuming.

Oats contain phytic acid. Soaking the whole grain for extended lengths of time helps to reduce phytic acid in overnight oats.

But what if all the liquid is gone? The longer the oats sit in the fridge, the more liquid they will absorb. It is important to add enough liquid to avoid dry oats.

If you are meal prepping a couple of days in advance, add a slightly more liquid than if you were eating sooner. This will result in extra creamy oats when served a few days later.

If you didn’t put enough liquid into the jar, you can always add a splash when serving.

Make sure to not overdo it with the liquid. Oatmeal soup is not the consistency that you are looking for, so tote the line with a careful balance.

Experiment with the basic overnight oats ratio to find your perfect balance. Oats are a dry grain that absorbs moisture from the air. Oats stored in the pantry have varying degrees of moisture levels.

Additionally, if you choose to add mix-ins before refrigerating then that can ultimately affect the liquid to oats ratio.

If these tips weren’t enough, Healthy Green Cooking on YouTube has a few more tips!

Can You Heat Overnight Oats?

Overnight oats are typically eaten cold, which makes the ultimate ready-to-eat meal prep. Not only are they quick and easy breakfasts, but they don’t need to be heated.

However, some people prefer to warm them up so they can eat hot overnight oats.

Here are the two easiest ways to heat overnight oats:

Microwave: Transfer the soaked oats to a microwave-safe bowl and heat to the temperature you are happy with.
Stovetop: Transfer the cold oats to a pot and place on low heat. Stir continuously so that the bottom of the pan does not burn. Heat until the oats reach a suitable temperature.

Shelf Life of Overnight Oats

For best results, store plain overnight oats in the fridge. The more add-ins, the higher the chance of the oatmeal changing taste, texture, or shelf life.

Overnight Oats with Fruit

If you enjoy eating overnight oats with fruit, it is best to eat within 2 days of preparation. Although they will probably be safe to eat for up to 5 days, use caution and check for any signs that the oats have gone bad.

If you don’t mix the fruit in with your overnight oats, then top the no-cook oatmeal with fruit.

Oatmeal with fruit mix-ins looks appealing when sitting in a clear glass jar inside the fridge.

But, is storing overnight oats with fruit the most efficient way? Having fruit mixed in with oats will blend into the flavor and texture of the soaked oatmeal.

Overnight oats are already mushy, so adding fruit to the mixture will not harm the consistency.

Overnight Oats with Milk

How long overnight oats will last in the fridge ultimately depends on the expiration date of the products mixed in.

When using milk, check to make sure that the milk has not expired. If the date is 3 days away, then you should eat the overnight oats within 3 days.

However, if the milk is fresh, then the overnight oats should last for up to 5 days.

Overnight Oats with Yogurt

Overnight oats with yogurt can last for up to 5 days in the fridge. Yogurt makes the soaked oats taste extra creamy, and the probiotics are an added benefit to aid digestion.

Before mixing with the oats, check the expiration date of the yogurt. If the date is quickly approaching, eat the oatmeal before the time passes by.