Comfort Foods 101: The Science Behind Outstanding Bone Broths

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Have you found yourself stress eating in the past few weeks?

I know many of us are looking for consolation in our foods as we attempt to sit out the coronavirus pandemic. Our desire to be comforted in these times can lead us to make poor or lackluster dietary choices. Haphazardly reaching for cakes, cookies, ice cream, pizza or fast food will yield an outcome which is anything but nourishing.

As pastry shops and local restaurants also take the hit, they have started parading us with messages that say, “we now have delivery!”

It is easier than ever to receive a surplus of low nutritive foods delivered directly to our doors. These are precisely the types foods that promote increased burdens on our already stressed out systems.

If we choose to give in to our dietary vices, we will inevitably allow let them to dictate our wellbeing. An alternative is to leverage this time and use it to improve our health.

In times of hardship we must instead turn to our kitchens and learn to provide for our bodies in a supportive manner. Slowly prepared homecooked meals will provide the type of enrichment which will truly comfort our mind, body and souls.

Still with me?

Let’s begin with the basics.

Bone Broth 101

There is nothing quite as soothing as a bowl of homemade soup made from a base of slow cooked bones and vegetables.

Taking the extra steps to slow simmer (or pressure cook) a homemade broth can mean the difference between a decent soup and a culinary masterpiece.

Although the premise behind making bone broths is pretty standard, there are measures to ensure your collagen content is maximal, vegetables are perfectly cooked and fat ratio is health promoting rather than sabotaging.

To ensure your bone broth is world class you need to make sure every ingredient which enters your pot is immaculate.

Bone broths are not a place to put throw frostbitten bones, old vegetables, stale spices or even unfiltered tap water.

As aforementioned, to produce ‘outstanding’ broths everything needs to be selected with utmost care.

The Bones:

You can find bones in every grocery store. However, just because they are readily available doesn’t make them all your best choice.

We know conclusively from the literature that grass-fed beef has a superior lipid profile in comparison to grain-fed meat.[1][2]

However, we also know that fat tissue is generally regarded as the site of toxin accumulation. We see this in people[3] and in animals[4].

The omnipresence of dioxin like compounds (DLCs) and persistent organic pollutants (POPs) in our food supply is linked in part to their ability to resist biodegradation.3[5] Their potential for harm in the human body cannot be understated.[3]

While we want to encourage a balanced consumption of animal fat in our diets, we simultaneously need to be considerate of their potential to carry undesirable toxicity.

Bones contain a wealth of fat from within the marrow. When purchasing larger bones it is not uncommon to find segments of animal fat attached to the bone. In light of this we need to ensure our bone selection is always of the highest quality.

Animals sourced from remote farms away from industrialized sectors and commercial farming will be your best bet as chemical contaminants will migrate via vapour, sediment and water.[5]

This means you will have to do a little of your own research when sourcing out the best bones.

When selecting your bones I recommend only a small ratio of marrow bones to other bones: knuckle, neck, carcass, feet etc. This is to prevent your broth from getting too fatty.

Here in Edmonton, Alberta I order direct from TK Ranch. Their offer uncontested standards for the ethical treatment of livestock in conjunction with land and pasture stewardship. Their cattle are raised in the wild Northern Fescue prairies and are all stringently grass-fed/grass-finished. These are the types of standards I encourage you to seek out as well.

While many chefs insist that roasting the bones in advance is a must, I have some personal reservations with this. While the finished product made from roasted bones might have a deeper flavor profile, my concerns are linked to the potential for fat oxidation and to a lesser extent the production of heterocyclic aromatic amines.[6] Oxidized fats and heterocyclic amines are the negative implications of subjecting animal fats and proteins to scorching temperatures. These compounds are notoriously damaging to our physiological function.[7] In light of this I recommend forgoing the roasting step or using it only on occasion.

The Acid:

A good bone broth will require the addition of a little acid. An acidifying agent is added with two primary intentions. It will encourage the demineralization of your carefully selected bones. Don’t expect this to be the primary mineral input into your broth however.[8]  You will need to fill the gap by adding vegetables to your broth for a truly rich mineral content.

The addition of acid will also support the extraction of collagen from within the matrix of the bone. The collagen content is what gives a good bone broth that strikingly indulgent texture.

The most commonly used acids for bone broths include dry white wine, dry red wine, apple cider vinegar, or white vinegar.

Here is a good point of reference when deciding how much acid to add to your broth:

~1/4 cup of dry wine for every 4-6 L of broth

~1 Tbsp of white vinegar or apple cider vinegar for every 4-6 L of broth

Wine will change up the flavour profile slightly so experiment with both to determine which you prefer.

The Vegetables:

There are two primary ways to using vegetables in your bone broth. You can use vegetables strictly for mineral content and flavouring which are then to be discarded with the bones. Or you can use the vegetables to flavour the broth but also consume with the final soup.

If you plan on using the vegetables for flavoring you want to include them in the final 4-8 hours of cooking time in a simmering pot. In a pressure cooker I recommend no more than 2 hours. This is to avoid bitter tastes from over cooking the vegetables.

If you plan on consuming the vegetables in the final product and prefer them to have a little bite, you will need to be considerate of timing. I recommend adding them for no more 45mins-1 hr in a simmering pot, or 25-35 minutes in a pressure cooker of final cooking time.

The most popular vegetable choices are: onions, carrots, celery, leeks, and herbs like rosemary and thyme.

Be cautious with garlic, it can impart a very aggressive flavor which can throw off an entire pot of broth. Remember, it’s the bones which are the centerpiece, not the add ins.

While some chefs prefer to caramelize the vegetables in a pan with cooking oil before adding it to the broth, my warnings for scorched and oxidized fats remain consistent here. For purity I suggest adding the fresh vegetables directly to the pot.

The Spices:

With bone broths simple is best. The less complicated your flavorings, the more well-rounded your flavor profile will be. The last thing you want to hear is a comment like, “wow you can really taste that [insert spice name.]”

I don’t recommend much else than a few dashes of cayenne, black pepper and salt.

The Extras (Collagen Maximizers):

It seems like everyone is arguing about collagen these days. Like many things, reading up on collagen brings you into a convoluted maze of anecdotal claims vs scientific facts.

I find the overall debate surrounding collagen takes away from the more fundamental aspects of soups and bone broths: general nourishment. Bone broths are still a rich source of nutrients and your body will delegate to itself how it will use that nutrient supply.

I apologize in advance but I can’t guarantee your hair will grow faster, you will look younger or your arthritis will be a thing of the past. I can guarantee, that if you take the time to make an incredible bone broth, you will be rewarded with a meal that will make you feel warm and comforted.

In the same breath, collagen is what makes the soup silky and rich. For those who are always chasing tactics to increase their soup’s collagen content, look no further than to my secret ingredient: chicken’s feet.

Once you get past the squeamish factor you will soon find adding 1-2 lbs of chickens feet to your broths will produce soup worthy of awards.

Adding chicken’s feet is like deciding to study five minutes for a university exam before getting an A+. It’s just too easy. You will feel like you cheated the system somehow.

Because the flavor profile of chicken’s feet is so neutral, you can add it to any type of bone broth: beef, porcine, wild game, or poultry.

Fast Tip: Cut the claws off the chicken’s feet to avoid off flavors in the bone broth.

The second magic ingredient to maximize collagen is: beef tendon.

Beef tendon is a very tough structure which breaks down into a jello-like mass during long periods of cooking. Beef tendon is made of up to 85% collagen. It is also delicious. Adding it in during the last 1/3 of cooking time prevents it from disintegrating too much and makes the texture more appealing.

The Time:

Complete extraction of the nutrients from bones takes a great deal of time. If simmering a large pot on the stove you will need approximately 24-36 hours of simmer time.

I much prefer using a pressure cooker because you can reduce the total cooking time down to a little less than 1/3 with stellar results. Efficiency is king in my world.

The Ratios:

The amount of bones you add relative to water will be variable based on your preferences. If you use many bones and you give your broth very little room for liquid but get a very thick end product, too few bones and you get a broth that lacks density.

Aim for ~3-4lbs of bones for every 6-12 cups of liquid. Again, this is variable based on which bones you select and how thick you want your broth to be.

The Tricks:

The one tool you need to buy is a fat skimmer.

A finished bone broth should only have a tiny bit of fat on top, say 1-4% fat by volume. This can only occur if you take the time to skim and discard the surface layer of fat that forms during cooking. If you don’t remove this layer of fat, you could be drinking cups and cups of fat while you finish your soup. At 9 calories per gram of fat, this could nudge your weight scale in the wrong direction. You’ve been warned.

Fast Tip: Bone broth can be frozen it in wide mouth mason jars that will keep well for months on end. Be sure to remove all the vegetables if you intend on freezing your broth. The texture of vegetables become compromised when precooked then frozen.

Naomi’s Pressure Cooker Bone Broth

1 Large Beef of Pork Knuckle Bone (frozen)
2 Lbs. Chicken’s Feet (defrosted and claws removed)
1 Lb. Beef Tendon (frozen)
5 Stalks Celery
8 Large Carrots
1 Medium Onion
1 Tbsp. Apple Cider Vinegar
¼ Tsp. Cayenne
2 Tsp. Salt
½ Tsp. Black Pepper

  1. In an Instant pot add chicken’s feet, knuckle bone, salt, pepper and cayenne and fill water up to the 8-cup mark. Cook for 4 hours on Meat/Stew function. (Two hrs is the max time limit on my pot so I return to the pot to reset for hour two to four. I’m not sure if this is the case with the newer models.)
  2. Allow natural release, open lid and skim off fat layer. Add in beef tendon but do not remove any bones. Cook again for 2 hours on Meat/Stew function.
  3. Allow natural release, open lid and skim off fat layer. Remove all parts (feet, knuckle, and tendon). Discard feet and knuckle. Chop tendon into bite size pieces and return to broth.
  4. Chop vegetables into small pieces. Add to broth. Close lid and set on soup function for 35 minutes.
  5. Allow natural release.
  6. Enjoy?

[1] Daley, Cynthia A et al. “A review of fatty acid profiles and antioxidant content in grass-fed and grain fed beef.” Nutrition Journal, 9(10), 2010.
[2] Kresser, Chris, “Why Grass-Fed Trumps Grain-Fed”, August 12, 2019,
[3] Jackson, Erin et al. “Adipose Tissue as a Site of Toxin Accumulation.” Compr Physiol, 7(4), 2018 Sept 12, 1085-1135.
[4] Roeder RA et al. “Assessment of dioxins in foods from animal origins.” J Anim Sci., 76(1), 1998 Jan, 142-51.
[5]  Committee on the Implications of Dion in the Food Supply, “Dioxins and Dioxin-like Compounds in the Food Supply: Strategies to Decrease Exposure”, National Research Council, 2003.
[6] Gibis, Monika. “Heterocyclic Aromatic Amines in Cooked Meat Products: Causes, Formation, Occurrence, and Risk Assessment” Comprehensive Reviews in Food Science and Food Safety. Volume 15, 2016, 269-302.
[7] Sugimura, Takashi. “Heterocyclic amines: Mutagens/carcinogens produced during cooking of meat and fish” Cancer Sci, 95(4), 2004 Apr, 290-299
[8] Dubois, Lawrence. “Bone Broth Analysis: Reader Research”, alive Editorial, November 5, 2014,

Contributed by Naomi Sachs, B.Sc., A.C.H.N., PFT

Fully-certified since 2015, Naomi has been successfully coaching clients throughout North America and facilitating their self-growth in the nutrition and fitness realm. If you are feeling overwhelmed by the myriad of health strategies available, her services aim to introduce clarity and self-motivation.