Cocoa solids are the low-fat component of chocolate

Chocolate

Chocolate is a raw or processed food produced from the seed of the tropical Theobroma cacao tree. Cacao has been cultivated for at least three millennia in Mexico, Central and South America. Its earliest documented use is around 1100 BC...

. When sold as an end product, it may also be called cocoa powder, cocoa, and cacao.
In contrast, the fatty component of chocolate is cocoa butter

Cocoa butter

Cocoa butter, also called theobroma oil, is a pale-yellow, pure edible vegetable fat extracted from the cocoa bean. It is used to make chocolate, biscuits, and baked goods, as well as some pharmaceuticals, ointments, and toiletries...

. Cocoa butter makes up for 50% to 57% of the weight of cocoa beans and gives chocolate its characteristic melting properties. Cocoa liquor

Chocolate liquor

Chocolate liquor is pure chocolate in its liquid form. Like the cocoa beans from which it is produced, it contains both cocoa solids and cocoa butter in roughly equal proportion....

 is the melted combination of cocoa butter and cocoa solids. Cocoa solids are obtained by extraction from the cocoa bean.

Extraction

Cocoa powder is extracted from roasted, cleaned, deshelled cocoa beans and grinded into a paste, called chocolate liquor. Pressing and milling the pressed chocolate liquor separates the cocoa powder from the fat. This may be accomplished by a press

Ram press (food)

A ram press is a device or machine commonly used to press items with a mechanical ram, such as with a plunger, piston, force pump, or hydraulic ram. In food preparation, there are various kinds of ram presses:...

, or by the Broma process

Broma process

The Broma process is a method used to remove cocoa butter from cocoa mass, leaving cocoa solids . In about 1865 someone at the Domingo Ghirardelli factory discovered that by hanging a bag of cocoa mass in a warm room, the cocoa butter would drip off, leaving behind a residue that can then be...

. The resulting cocoa powder can be further processed with a hydroxide or carbonate of sodium of potassium. Natural process cocoa powder (not processed) has a tart, bitter taste and is light in color. Processed cocoa powders are deeper in color and richer in flavour. Alkalization reduces the sour, bitter properties of natural cocoa powder improving the taste. Alkalization can also alter the solubility of the cocoa powder. Dutch process chocolate

Dutch process chocolate

Dutch process chocolate, or Dutched chocolate, is chocolate that has been treated with an alkalizing agent to modify its color and give it a milder taste compared to "natural cocoa" extracted with the Broma process...

 has been treated so as to neutralize the acidity and has a milder flavor; it is also the traditional chocolate brown in color.

Physical Properties

Cocoa solids can range from a light brown to a deep reddish brown color. The varying color corresponds to the pH value of the Cocoa. Safe, acceptable pH for cocoa ranges from 5.4 to 8.1 depending on how processed the cocoa powder is. Cocoa with a pH of 5.4-5.8 are considered natural powders and have a light brown color. Lightly alkalized cocoa solids have a pH of 6.8-7.2 and are a darker brown color. Moderately alkalized cocoa solids have a pH of 7.2-7.5 and have a deep reddish brown color, and heavily alkalized powders with a pH of 7.5-8.1 have dark red and black colors.

Nutrition

Cocoa powder contains several minerals including calcium, copper, magnesium, phosphorus, potassium, sodium and zinc. All of these minerals are found in greater quantities in cocoa powder than either cocoa butter or cocoa liquor. Cocoa solids also contain 230mg of caffeine and 2057mg of theobromine per 100g, which are mostly absent from the other components of the cocoa bean.

Flavenoids

Cocoa powder is rich in flavonoids, a type of polyphenolic. The amount of flavonoids depends on the amount of processing and manufacturing the cocoa powder undergoes, but cocoa powder can contain up to 10% its weight in flavonoids. Flavanols are one of six compounds futher classified as flavenoids. Flavanols, which are also found in fruits and vegetables, are linked to certain health benefits linked to coronary heart disease and stroke. The topic of how flavanols benefit cardiovascular health is still under debate. It has been suggested that the flavanols may take part in mechanisms such as nitric oxide and antioxidant, anti-inflammatory, and antiplatelet effects. Benefiting these mechanisms may improve endothelial function, lipid levels, blood pressure and insulin resistance.
Accordingly, health professionals recommend consuming chocolate in forms that are high in cocoa solids while low in cocoa butter, such as hot cocoa.