The Science of pH: What Makes a Broth Acidic or Alkaline?
To understand bone broth's pH, it helps to first grasp the basic concept of the pH scale. Ranging from 0 to 14, a pH below 7 is acidic, above 7 is alkaline (or basic), and 7 is neutral. While the body's blood pH is tightly regulated and not significantly influenced by dietary choices, foods are often categorized as acid-forming or alkaline-forming after digestion.
For bone broth, the final pH is a balance between the starting ingredients and the lengthy cooking process. When animal bones are simmered in water, they release minerals such as calcium, magnesium, and phosphorus. These minerals are naturally alkaline, which can increase the broth's pH. A study published in Essential and Toxic Metals in Animal Bone Broths observed that broth prepared with only water had a mean pH level of 8–8.5, indicating it was slightly alkaline. This suggests that a traditionally prepared, unacidified broth tends to lean towards the alkaline side.
The Vinegar Dilemma: How Cooking Changes the pH
Most traditional bone broth recipes call for adding a splash of acid, such as apple cider vinegar, at the start of the cooking process. The purpose of this step is to help break down the collagen and connective tissues, extracting minerals and creating a more nutrient-dense, flavorful, and gelatinous final product. However, this also has a direct impact on the broth's pH. The same study that found a non-acidified broth to be alkaline showed that when a small amount of vinegar was added, the broth's pH dropped significantly to the acidic range of 5–6. Therefore, whether your bone broth is acidic or alkaline largely depends on this single recipe choice.
The Health Benefits Beyond Acidity
Regardless of its final pH, the true value of bone broth lies in the nutrients it provides. These components are responsible for the various health benefits often attributed to the popular drink:
- Amino Acids and Gut Health: Bone broth is rich in amino acids like glutamine and glycine, which can have anti-inflammatory effects. Glutamine is known to strengthen the gut lining, potentially helping to heal "leaky gut" syndrome and soothe the digestive tract. Glycine also supports digestion by aiding in the production of stomach acid and digestive enzymes.
- Joint Support from Collagen and Gelatin: The prolonged simmering process breaks down collagen from bones and connective tissues, turning it into gelatin. While the amount of collagen in bone broth may not be as high as in supplements, the amino acids it provides support the body's own connective tissue, which can help with joint health.
- Minerals and Hydration: While the mineral content, including calcium and magnesium, is modest compared to the daily recommended intake, it contributes to overall nutrition. The high water content and presence of electrolytes like sodium and potassium also make bone broth a great option for hydration.
Comparison: Homemade vs. Store-Bought Bone Broth
The debate over bone broth's pH and benefits extends to the commercial products on the market. There are notable differences between what you can make at home and what you can buy at the store.
| Feature | Homemade Bone Broth | Store-Bought Bone Broth |
|---|---|---|
| pH Level | Variable, depends on added ingredients like vinegar. Can be neutral to slightly alkaline without acid. | Variable; recipes and quality differ. Often contains additives and might not be true, long-simmered bone broth. |
| Cooking Time | Typically simmered for 12-24+ hours to extract maximum nutrients. | Varies widely. Some are made quickly and are closer to a standard stock, with fewer extracted nutrients. |
| Cost | Generally more cost-effective, using leftover scraps and bones. | Can be expensive, especially for high-quality, long-simmered products. |
| Ingredients | You have complete control over all ingredients, including acid levels, vegetables, and seasoning. | Ingredient lists can contain hidden flavors, high sodium, or artificial components. |
| Nutrient Density | Often richer in gelatin and nutrients due to longer cooking times and better bone selection. | Can be less concentrated unless specifically stated otherwise. Check for a gelatinous texture when cold. |
Making an Alkaline-Focused Bone Broth
If you are aiming for a more alkaline-leaning broth (which is not guaranteed to impact your body's pH but can align with dietary preferences), here are some tips:
- Skip the Vinegar: The most direct way to avoid making an acidic broth is to omit the vinegar or other acidic ingredients from the recipe. While this might slightly reduce the mineral extraction, a long, slow simmer will still release key nutrients.
- Choose Alkaline-Forming Vegetables: Add plenty of alkaline-forming vegetables, such as carrots, celery, and onions, along with herbs and spices. While they may not dramatically alter the final pH, they contribute valuable nutrients and flavor.
- Use High-Quality Bones: Source bones from healthy, grass-fed, or organic animals. Marrow bones, knuckle bones, and feet are excellent choices for creating a thick, gelatinous broth.
- Slow Cook for Maximum Extraction: Simmer the broth for an extended period, ideally 12-24 hours. The long, low-temperature cooking time is essential for drawing out the most nutrients.
Conclusion
The question of whether bone broth is acidic or alkaline is not a simple one, as the answer depends on the preparation method. A broth made with added acid will be acidic, while one simmered for a long time without acid may be neutral or slightly alkaline due to mineral extraction. Ultimately, focusing on the broth's genuine health benefits—including its support for gut health, inflammation, and joints—provides a more accurate understanding of its value than relying on an oversimplified acid-alkaline classification. The body's own tightly regulated systems ensure that dietary pH has minimal impact on blood pH. Therefore, enjoy your bone broth for its rich, nourishing qualities, knowing that its health perks are not dependent on a specific pH label.
Further reading
For more detailed information on making bone broth and its nutritional properties, consider exploring resources from reputable culinary and health sites like MasterClass.
