Any food requiring a long cook time seems a natural fit for a crockpot, and bone broth is no exception. You can make great bone broth in a crockpot with a little know-how. Aside from quality bones, two key factors will determine your broth-making success:
Heat. We need heat to break down the ingredients and cook the broth ingredients until they are safe to eat. But if heat is not controlled properly, bitter flavors will be created and concentrated.
Water. Having plenty of water helps to break down the broth ingredients and insulate our ingredients from the effects of too much heat. If there is not enough water in the pot, the ingredients will scorch, and that tastes truly vile.
It’s important to know your crockpot really well before you risk losing expensive ingredients in a cooking disaster. Follow these guidelines to make sure your crockpot has the right stuff. Don’t assume that all crockpots are good for all cooking tasks; many are not. The crockpot that always makes delicious roasts and stews may be too hot or cold for broth-making.
Space and Size
Use the largest crockpot that you have. A 6 to 7 quart crockpot is best. Crockpots that are 4 quarts or less have very little space for water once we add several pounds of meat and bones, vegetables, and other savory ingredients to the crockpot. This not only limits our ability to keep ingredients from getting too hot, but also impacts how much bone broth we can make at a time. Have you attempted bone broth before in your crockpot, and after many hours of cooking yielded one quart jar of scary thick broth that tastes bitter? Having enough water in the crockpot to surround the bones and vegetables is critical. Be careful in how many ingredients you add to the crockpot in addition to the bones and/or meat. Consider using a blender or food processor to chop or puree the vegetables and herbs. The result will be just as delicious, and you will have a little extra room for water.
When cooking broth, don’t let your broth boil. A few minutes is fine; a few hours is not so good. The best temperature for making bone broth is 208 to 210 F.(1) The surface of the broth should barely move at all, or only in small bubbles beneath the surface. Some cooks call this a ‘lazy bubble.’ If your crockpot is able to maintain a steady temperature below boiling, keep an eye on the water level in the crockpot. Top off the water as needed. Most crockpots offer three settings: Keep Warm, Low, and High – and good luck finding out what those temperature settings really mean. The manufacturer may or may not publish this data. Additionally, some crock pots claim that Low and High are actually the same temperature! How is that possible? The heat element cycles on and off at slower or higher frequencies depending on whether the setting is on Keep Warm, Low or High, respectively. Got that? Good. Please draw a diagram to explain it to the rest of us. I just wish crockpots had the same control over temperature that ovens do.
Crockpots that are more than a few years old may run hotter or colder than expected. Even small appliances frequently lose their effectiveness over time. Your crockpot’s ability to maintain or cycle temperatures can be negatively affected as well. Check the temperature of your crockpot periodically as you make your first few batches of broth. Admittedly, this is a somewhat annoying task, but it’s only needed the first few times you use your crockpot to make broth. Try using an instant read thermometer with a probe and a programmable alarm. The probe will continSimilar models for grills are very useful to let you know what is happening in the crockpot while you aren’t staring at it directly. You may also find it helpful to use a tea, oven, or grill thermometer to spot check your crockpot temperature.
Arguably few home kitchens would survive a professional food safety inspection. We all have at least one naughty habit that we know is probably not the safest practice, but we do it anyway. Why? Because we keep getting away with it, and no one has died yet. That doesn’t mean I would tell you to do it. Go figure out your own bad habits! No piggybacking on mine.
Given the option of Keep Warm, Low, and High temperatures on a crockpot, many people assume that Keep Warm is a safe temperature to keep perpetual broth going. It isn’t always. Depending on your crockpot, the Keep Warm actual temperature could be between 140 F to 200 F. You need to check, unless you are cooking something for your enemies. Be safe.
We also assume that boiling will negate the life of any pathogens in our broth. That isn’t true. There are many heat-resistant microbes, some so resistant that they routinely hang in volcanoes. Is your crockpot hotter than a volcano? Probably not. Spores and bacterial toxins can remain in your broth even after long cook times. Checking the temperature of your broth during cooking for the first few times is advised, particularly if you are pregnant, feeding children, or nurturing yourself. Why make your body work harder to heal? Want to know more about broth food safety? Thankfully, the New York Times has you covered in a great article about the best food safety practices for stocks and broths.
Getting the Most from Your Ingredients
If you buy pastured or grass-fed meats, you likely love the taste – but the price? Not so much. Squeezing every bit of nutrition from those meats is important.
The Journal of Food Science published a fascinating article on the physicochemical properties of chicken stock. The ideal temperature range for flavor development is between 208 to 210 F. Broth cooked at this temperature contained more protein, had better viscosity (the body of the stock), and was rated better by tasters than products cooked at lower temperatures. At just a whisper below boiling, you will see a bubble rise to the surface every now and then. You may also see small bubbles below the surface. In fact, the broth may be so still that proteins on the surface develop a plastic-looking skin. Don’t worry about the skin. Unlike the skin on cooked milk, this skin will dissolve as soon as you stir the broth.
Collagen begins breaking down into gelatin starting around 140 to 160 F. Make sure your crockpot can hit these key temperatures. The temperature of crockpots vary from manufacturer to manufacturer, and the only way to know for sure is to check the temperature. Once you’ve had a good batch of broth from your crockpot, you will develop a routine and the confidence to let your crockpot cook unattended.
Bone broth as a medicinal food does not look like the wimpy stocks in cans and boxes. If you enjoy clearer bone broth, staying below the boiling point will help. Boiling your bone broth hard agitates the ingredients, causing more particles to be released into the water. This can cause the bone broth to become cloudy. I don’t mind cloudy personally; any nutrients from the bones are welcome in my broth. Why cook the bones to extract the benefits, only to filter them right out again?
Efficiency and Thriftiness
Some prefer to make multiple batches of bone broth from the same bones. Repeated use of the bones until the bones dissolve or crumble is a thrifty, useful practice and has a delightful French name: remouillage. Isn’t that a delightfully fancy word for recycling? If you plan on drinking bone broth frequently, or would like to be able to freeze enough broth for cooking, you may become frustrated with your crockpot’s size. I must confess I prefer using a 12 quart stockpot so that I can make one large batch of bone broth every week or so and use up every last bit of nutrition from the bones. I enjoy being able to squeeze 2 gallons of broth from a 3 pound stewing chicken. It’s nice to have the broth ready to go in the freezer for cooking or sipping. It’s a personal choice, however. Finding a way to make bone broth a low-stress task is critical to making bone broth part of your lifestyle.
(1)Krasnow, M., Bunch, T., Shoemaker, C. and Loss, C. R. (2012), Effects of Cooking Temperatures on the Physicochemical Properties and Consumer Acceptance of Chicken Stock. Journal of Food Science, 77: S19–S23.