10 Foods You Should Never Cook In Your Slow Cooker

Nov 05, 2024

Read this before you reach for your slow cooker.

Khara Scheppmann has 12 years of marketing and advertising experience, including proofreading and fact-checking. She previously worked at one of the largest advertising agencies in the southwest.

A slow cooker can be nothing short of a lifesaver during busy weeks. The handy appliance lets you prep your pot and move on with your day. The result? A delicious, home-cooked meal without spending hours in the kitchen. There's only one problem: some foods don't lend themselves to slow cooker preparation.

According to Allie Echeverria, a Fresh Starts Registry Expert and registered dietitian nutritionist from Atlanta, Georgia, certain foods are actually unsafe to prepare in a slow cooker. The last thing any of us want is to make ourselves sick over a homemade meal, so we asked her to explain which foods you should never prepare in a slow cooker.

According to Echeverria, cooking frozen chicken in a slow cooker may be unsafe. "The official USDA stance is that it is not safe to cook frozen chicken in a slow cooker," she reports. "The danger zone for food temperatures is between 40° and 140°F. That temperature range allows bacteria to rapidly multiply, which is why you're not supposed to allow food to be in that temperature range for longer than two hours."

Since slow cookers take a while to heat up and cook slowly (hence the name), this means that frozen chicken might spend too much time in that danger zone. Chicken needs to reach an internal temperature of 165°F to be safe to eat, so don't chance it. Be sure to thaw frozen chicken before you put it in a slow cooker.

If you're planning to break out your favorite slow-cooker chili recipe this weekend, just be sure you don't start with dried beans.

"Kidney beans contain phytohemagglutinin (PHA), which is a type of protein called lectin. PHA is toxic in high doses. Fortunately for kidney bean lovers, the toxin is destroyed when boiled at 212°F for 30 minutes," Echeverria explained.

This means that although it may be perfectly safe to prepare dried kidney beans on the stovetop, the slow cooker won't reach the necessary temperature quickly enough.

If you've got a big pot of leftovers, it may be tempting to throw them in the slow cooker, but Echeverria says this isn't a good idea.

"Do not use a slow cooker to reheat leftovers, even if you originally cooked the food in the slow cooker," she cautioned. "The low temperatures can allow prepared foods to spend too much time in the unsafe food temperature zone."

Instead, she suggests reheating leftovers on the stove or in the microwave. After that, she says it's perfectly fine to use the slow cooker to keep them warm for serving.

Echeverria says food safety isn't the only concern when it comes to cooking food in a slow cooker. Some foods can be tricky because they need to be timed just right in order to taste their best when you prepare them slowly.

According to Echeverria, lobsters, crabs, oysters, clams, and mussels can all be safely cooked in a slow cooker. However, if you've ever cooked shellfish before, you know it cooks quickly no matter which method you use.

If you overcook shellfish, it becomes tasteless and rubbery. For this reason, Echeverria recommends adding shellfish an hour before the full meal is ready or sometimes even minutes before it finishes cooking, depending on the recipe.

"Raw meat is a slow-cooker staple, but you may need to add it to the pot before adding other ingredients like green vegetables," she shared. "Browning meat in a skillet before adding it to the slow cooker has been a game-changer for my slow-cooker meals. It adds a caramelized flavor, cuts down the grease, and can allow you to cook the meat and remaining ingredients in the slow cooker at the same temperature for the same amount of time."

So, go ahead and cook raw meat in your slow cooker. Just be sure to give it a head start over the rest of your ingredients.

Slow cooking will destroy the color, flavor, and texture of delicate fresh herbs. Save them and stir them in at the end of the cooking process, or use them as a garnish.

Slow cookers are excellent for making soups and stews, but not for recipes that are milk- or -cream based or that have a lot of cheese. Long cook times will break down dairy products, making them curdle or separate. For best results, stir in dairy-based ingredients at the end of the cook time, like in this Creamy Potato Soup.

Similar to dairy products, pasta will break down and turn mushy when cooked low and slow. You can either stir in cooked noodles (like macaroni or ravioli) at the end of the cook time, or choose recipes that have a cook time of four hours or less, like this spaghetti casserole.

While there are some exceptions, like long-simmered collard greens, bacon isn't at its best when slow cooked. A long cook time makes the smoked meat mushy. If you're looking for salty, smoky richness, substitute a ham hock for bacon. It can stand up to long cook times and will infuse your dish with flavor. And you can always top a dish with chopped, cooked bacon.

Chicken isn't the only frozen food to avoid using in a slow cooker. Any frozen ingredient will take longer to defrost and cook, which will affect cook times. Depending on the ingredient—frozen vegetables will take much less time to defrost than frozen beef—it could make a big difference in the dish.

U.S. Department of Agriculture. Slow cookers and food safety.

U.S. Department of Agriculture. How temperatures affect food.

The Ohio State University, College of Food, Agricultural, and Environmental Sciences. Chow Line: Dry kidney beans need to be boiled.