You might see the words “bone broth” on menus more frequently these days, it seems simple stock is getting rebranded and pitched back to us as a cure-all restorative drink. Now, I’m not complaining that stock is back in the limelight, but let’s not be deluded with fancy marketing. Stock (a.k.a. bone broth) is nearly as old as any cooking technique to be found in your kitchen. It is, of course, simple, practical, and healthy!
You’ve certainly heard chefs say loudly, “Make your own stock, it’s better than anything you can buy.” And they aren’t wrong. But if you’ve been holding off because you think it’s too labor-intensive, then now is the time to tune in and pay attention. Making stock (or bone broth if you insist on pop-culture terminology) is easy and you should start today.
The main act of stock-making is the diffusion of various proteins, vitamins, and minerals found in animal bones into a large quantity of water. We often think of protein as muscle tissue, but in fact, proteins are large molecules made of chained amino acids (the building blocks of life) that can be found in many bodily tissues. Cartilage, hair, and yes, muscle, these are all composed of various proteins. In addition to protein diffusion, we are accessing the power of marrow while making stock. Bone marrow is the densest source of fat-soluble vitamins in animal bodies, and is responsible for the creation of blood cells in any living creature.
Collagen is one of the many proteins to be found in bones and connective tissues. It is, in my opinion, the most important ingredient in any stock (or bone broth). Joints are especially high in collagen, because they are filled with cartilage (both from ligament and tendon). When making stock, take this into consideration. A chicken breast will certainly impart some flavor, but because there is little connective tissue rippling that muscle, the final product will not have the silky smooth texture of a fine broth.
I use chicken legs, backs, necks, and feet for my chicken stock. Those pieces of the bird are full of tiny joints that all require cartilage to connect them together. But first, I roast my bones and bits. You can, of course, cook stock from un-roasted bones, but the added high heat induces reactions that lead to greater flavor. Consider this: when cooking any piece of meat, you sear the outside in order to generate the most flavor, yes? Roasting bones is the same as searing meat. It adds depth to the final dish.
The final, and most important, ingredients in stock are time and temperature. Many of us routinely boil bones at a rapid pace to speed up the seemingly difficult process. But beware! High heat can emulsify fat that begins to melt from skin and bone, giving the final stock a cloudy look and taste. The ideal temperature is the zone in which collagen denatures (or breaks down) into gelatin. Yes, the notion that horse bones were once boiled to make the stuff of Jello is correct. As collagen unravels, it hydrolyzes (which is to say, it undergoes a chemical reaction with water). That hydrolysis leads to the generation of gelatin in the solution. And what is that temperature zone? 185-200 degrees is my ideal.
Remember, water boils at 212 degrees, so the closer we approach that temperature, the more activity we will have in the stock (which leads to the aforementioned fat emulsification). But because such a precise temperature is needed, why bother leaving a thermometer in it on the stove? Simply put the stockpot, uncovered, in a warm oven and walk away.
How long should you walk away? At least 12 hours by my clock, but as much as 24 or even 48 depending on the bones you’re breaking down. Chicken proteins are simpler to hydrolyze than beef, so chicken bone broth will take less time than beef broth (though you can easily let your chicken stock heat for 24 hours). Chicken bones are also more porous than beef, which helps to account for the time difference. The final dish should be a solid at room temperature! Yes, the solution should be so thoroughly suffused with gelatin that when pulled out of the refrigerator it shakes like a bowl of jello.
As for health: beware, bone broth is often over-sold as a cure-all. There was a study done in 2000 that linked chicken broth to a mild reduction in inflammation and symptoms of upper respiratory tract infection, but anything other than that has been unproven. Some say that the collagen in stock will help you regrow your own collagen in your joints and skin. This is unfounded at best. We break down gelatin in our digestive system into separate amino acids (the building blocks of proteins) which are then used however the body desires. We cannot simply have better skin or joints from drinking delicious broth.
But, of course, vitamin dense soups and warm liquids are always a boon to the immune system. I'm not saying broth is unhealthy, simply under-researched. The protein dissolved in bone broth is so easily digested it is absorbed into your body much more quickly than the protein in a piece of cooked chicken or beef. Chicken and/or beef stocks are nutrient-dense solutions that are good for anyone, anywhere. Just because we cannot state specific benefits to drinking broth doesn't discount its place in historical health. After all, we’ve been drinking chicken soup to cure colds for centuries. A warm infusion of proteins, vitamins, and minerals will always be healthful and hopefully as we progress with scientific research we'll be able to determine exactly what bone broth does in our bodies once consumed.