Leaving Your Slow Cooker On For More Than 8 Hours – What You Need To Know

Slow cookers have revolutionised cooking for many by being able to leave it on while going out, doing school runs and having the meal ready without having to put in too much labour and time. Though there are some things you should know before leaving your slow cooker on for too long at a time.

If you are wanting to leave your slow cooker on for longer on for 8 hours you will need to make sure that it is on a solid surface, on a low setting or on a timer to ensure it is safe. Make sure that the slow cooker is away from anything else and you are using a slow cooker with a timer.

In this article, I am going to be talking about the dangers of using a slow cooker for over 8 hours, what you need to know if you plan to do so and what kind of foods can be cooked for longer than 8 hours.

Factors Dependent When Leaving Your Slow Cooker For More Than 8 Hours

The Type of Food Inside

Some recipes are safe to cook for more than 8 hours, while some can only be cooked for 5 to 6 hours (although, they can be left in the slow cooker at a warm temperature). Foods that require a long time to get tender can be left for more than 8 hours in a slow cooker e.g meat etc.

Vegetables that require minimal heat will need to be attended to before 8 hours elapses, (in this case, root vegetables are excluded). 

The Slow Cooker Settings

Leaving food in a plugged-in slow cooker without proper setting is not ideal. Some settings need to be in place, some brands have settings ranging from slow to medium and high heat. 

Also, new models feature adjustable settings that can automatically switch to “keep warm” after a long cooking time (thanks to technology). Some can also be set to switch off once the food reaches a preset cooking temperature.  

A slow cooker can be let for more than 8 hours if the cooking temperature is right. 

Slow Cooker Brand

Some brands feature a “keep warm” mode after cooking, and then buffer time. While this should be common with slow cookers, a few brands don’t have it. Some brands have a 24-hour cycle with an automated system to shut down after a reasonable cooking time. So leaving it on for 8 hours or more is acceptable in this case. 

It is pertinent to note that an average slow cooker (whether premium or low-end brand) can withstand  8 hours of plug-in time cooking without being attended to.

For instance, Slow cooker users have reportedly plugged in the appliance by 8 AM and left for work, came back by 10 PM, and discovered it is still on without any damage to the food, nor the slow cooker.

As the name implies, a slow cooker is meant to cook for a long time, so leaving it on for 8 hours or more is not harmful. 

Is It Safe To Leave On For More Than 8 Hours?

Even though it leaves your food very tender, it is safe to leave your slow cooker on for 8 hours. A slow cooker is built to handle heat for a long time and if the over-tenderized nature of the food left in the slow cooker isn’t a concern to the user, then it’s ok to leave it on for a long time (say 7 to 10 hours). 

It is also safe to leave your slow cooker on for 8 hours or more if the food being prepared requires proper tenderness before it is considered healthy to eat.

Most slow cookers have timers that regulate the cooking time and heating temperature, once the set time reaches, it goes off and automatically switches to a warm mode.

With this timer feature, it is safe to leave it on for 8 hours. 

While it is not too harmful to leave your slow cooker on for 8 hours, it’s important to also consider the nature of food being left. Some foods that require being served together might disintegrate. A slow cooker without a keep warm feature might over-mash some recipes when left on for a long time.

Some might also get dried out and burn if left on for a long time. In these scenarios, leaving a slow cooker on for 8 hours is not ideal. 

Old slow cookers are not safe to leave on for 8 hours, especially those that operate with minimal temperature options. Operating on a too high or too low temperature over 7 hours might be harmful to a slow cooker or burn out the food. Although some users invest in a separate plug-in timer to give old slow cookers an automated feature, making it safe to leave on for 8hours. 

Furthermore, the size of food is another determining factor when leaving old cookers on. Ideally, a small portion of food should not be left on in a slow cooker for a long time as the heat integration is usually higher. While larger portions can be left on for 8 hours or more to afford ample time for heat to integrate. It is also safe when set on a low temperature while considering the recipe. 

How Long Can I Leave My Slow Cooker On For?

The maximum time to leave a slow cooker on is 12 hours. Even though some slow cooker brands automatically go off after 24 hours of heating, it is not recommended, as it can overcook the food inside or tamper with the lifespan of the slow cooker.  

Also, cooking by the timeframe of your recipe is the ideal time to leave your slow cooker on. While most slow cooker recipes are planned to be cooked for 6 to 8 hours, they can mash or go unhealthy when cooked more than the stipulated time. 

Setting the right temperature is another determining factor, a meal that takes 8 to 10 hours on slow heat to be ready should not be set to 8 to 10 hours on high heat.

Also, older models of a slow cooker are not automated to switch between settings, so leaving it on over a long period is not ideal, instead, you switch to keep warm after a while. An automated slow cooker that features a digital timer can be left on for 12 hours and over since it switches to a warm mode after the food is cooked. 

Although, constantly leaving a slow cooker on over an extended period is not ideal. Instead, it should be transferred to the refrigerator when it is cooked and not eaten immediately, as the warm settings of the slow cooker differ by models. Some slow cooker brands have 145°F as their warm settings while others have a lower or higher temperature. 

A warm setting of 145°F can be harmful when left on for a long time. Nutritionists have reportedly said that bacteria grow between 40° to 140°F, so leaving a cooked food in a slow cooker for too long after it was opened when being prepared is risky. 

All in all, with a proper setting, a slow cooker can be left on for 12 hours and more (should not be a constant practice though), as the settings switch to a safe temperature after cooking.

What Should I Know If I am Leaving My Slow Cooker On For More Than 8 Hours?

With a proper setting on a slow cooker, you can go about your day but, for safety purposes, here are some helpful tips: 

Set it to Keep on Low Heat After Cooking

If you will be out of the house for a long time, it is safe to set the slow cooker on low heat. For recipes that require high heat, save it till when you are in the house, to ensure proper cooking. Most high heat meals cook for less than 8 hours. 

For slow cookers without an automatic switch, leave it to cook on low heat before leaving the house. 

Avoid Placing it On a Delicate Surface

Whether you are leaving your slow cooker on for more than 8 hours or simply having a quick high heat cook, do place it on a heat proof surface. A countertop or wooden surface can be dangerous due to its texture, consider a tiled surface. Granite surfaces are also safe and heatproof. 

It Should Be Kept in an Airy Environment, Away from the Wall

A slow cooker is a heating appliance that emits heat from the sides. It is important to give it space for proper airflow, the cord should be placed far from the cooker. Also, keeping the cooker 6 to 7 inches away from the wall or other appliances is ideal. 

Fill the Slow Cooker Appropriately

Some slow cooker models have maximum filling points, do not go overboard, it’s safe to go below the “max mark”. Those without a max sign can be filled half or two-thirds full, as going above 3 quarters will overload the slow cooker, which will then overflow upon heating.

An overloaded slow cooker will evaporate liquid. Asides from the appropriate filling of ingredients, make sure the lid is tightly secured since it will be left for hours to avoid burning. 

Go For Slow Cookers with Timer and Auto Switch

Old slow cookers are straightforward, with limited functions, consider upgrading to a newer model or get a plug-in timer. They come very handily, especially at times when it is left on for more than 8 hours. 

Similarly, newer models of slow cookers automatically switch to keep warm after long hours of cooking. Some go off after 20 hours, going for slow cookers with these features are worth it.