Traditional bone broth in modern health and disease

Townsend Letter for Doctors and Patients,  Feb-March, 2005  by Allison Siebecker

• E-mail
• Print
• Link

Introduction

Broth, made from the bones of animals, has been consumed as a source of nourishment for humankind throughout the ages. It is a traditional remedy across cultures for the sick and weak. A classic folk treatment for colds and flu, it has also been used historically for ailments that affect connective tissues such as the gastrointestinal tract, the joints, the skin, the lungs, the muscles and the blood. Broth has fallen out of favor in most households today, probably due to the increased pace of life that has reduced home cooking in general. Far from being old-fashioned, broth (or stock) continues to be a staple in professional and gourmet cuisine, due to its unsurpassed flavor and body. It serves as the base for many recipes including soup, sauces and gravy. Broth is a valuable food and a valuable medicine, much too valuable to be forgotten or discounted in our modern times with our busy ways and jaded attitudes.

Definition

In general, broth is a liquid made by boiling meat, bones, or vegetables. There are many types of broths, based on what is being cooked. For example, Bieler Broth, a vegetable broth made with green beans, zucchini, and celery is a supportive remedy used in detoxification or cleansing protocols. ConsommE, a rich broth made from meat, is another example. It is prepared by reducing, or prolonged simmering. Stock is another word used synonymously with broth, though some chefs denote stock as being made from bones whereas broth is made from meat. In this paper the two names are used interchangeably. Soup is a similar term referring to simmered vegetables, meat, and seasonings, and is defined by Random House Webster's Dictionary as a liquid food. (1) The difference is that soup contains solids such as meat, beans, grains or vegetables (sometimes disguised by a puree) while a broth is the liquid in which solids have been simmered and then discarded. Soup is what we think of as having for a meal. Broth is a starting ingredient for soup, and must be prepared separately beforehand.

Method

The ingredients are as follows: bones from an animal, with or without meat and skin, enough water to just cover the bones, a splash of vinegar, and optional assorted vegetables or their scraps. Making broth requires almost no work, just put the bones in a pot, add water and vinegar, bring it to a simmer and walk away. No chopping or tending is needed.

Why then, don't people make it? Stock needs to be prepared in advance to mealtime. It needs to boil for hours, and the longer it simmers, the better it gets. An easy solution is to routinely put meat scraps into a pot, instead of the garbage can. Broth can just as easily be extracted from a single chicken breast bone as it can from a whole chicken, and it need not be raw. Broth can be allowed to simmer on lowest heat for a day or two. The greatest amount of work is at the end, when it must be strained, cooled, and put into containers, still not very troublesome. It can be kept in the refrigerator for about five days, or frozen for months. (2) With stock on hand, homemade soup can be ready for dinner within 20 minutes. (See Appendix A for more recipe details).

Nutritional Contents

Basically then, broth will contain the ingredients that are in bone. Covering and adhering to the ends of bones to form a joint, is cartilage. Therefore broth will also contain the ingredients that are in cartilage. Bone and cartilage are both classified as connective tissue. Connective tissue is one of the four basic tissue types that exist in animals. It functions to bind or hold together and to support and strengthen the body. Connective tissue consists of a matrix, and cells that secrete the matrix. The matrix is the material that fills the space between the cells and is therefore referred to as the extracellular matrix. It is composed of protein fibers, and ground substance, which can be a liquid, a get or a solid. Since the cells are few, it is the valuable nutrients from the matrixes of bone and cartilage, which create the substance called broth. (Table I).

Bone

The primary functions of bone are to provide a support framework, protect organs, store and release minerals, produce blood cells and store energy. In the matrix of bone, the protein, collagen, forms the fibers. Collagen has the ability to resist a pulling or tearing force, called tensile strength. It is flexible and rubbery. The other matrix component, the ground substance, is made of mineral salts. Calcium and phosphorus, in a composite called hydroxyapatite, and some calcium carbonate, form 65% of the ground substance. Water contributes 25%. The remaining 10% is formed by magnesium, sodium, potassium, sulfate and fluoride. (3,4) (Table I) The inorganic minerals form a solid ground substance and give bone its hardness. If bones were made only of collagen they would be rubbery, but if they were made only of minerals, they would be brittle. Together they make bone flexible and hard.

Bone Marrow

In a central cavity, bone also houses marrow. There are two types of bone marrow, red and yellow. Red bone marrow is the location for the manufacture of the cells in blood. It produces the cells in their immature forms. The final conversion into mature blood cells occurs outside the bone marrow. The cells made in the red marrow are myeloid stem cells, the precursors to red blood cells, and lymphoid stem cells, the precursors to white blood cells and platelets. Red blood cells carry and deliver oxygen to other cells, white blood cells are part of the immune system, and platelets allow for clotting. Red bone marrow also contains collagen protein fibers, sometimes called reticulin fibers, classified as type III collagen. (5) (Table I) In comparing why less chicken parts compared to beef parts are needed to produce a similarly strong tasting broth, the authors of The Best Recipe cookbook suggest that chicken bones have a higher concentration of red marrow, and that this considerably enhances flavor. (6)