Unsweetened cocoa or cacao (but not cocao) contains many valuable substances such as enzymes and antioxidants, and these are better retained when the cocoa beans aren’t roasted but raw.
General information about cocoa beans:
From Wikipedia: “The cocoa bean, also cacao bean or simply cocoa or cacao, is the dried and fully fermented fatty seed of Theobroma cacao, from which cocoa solids and cocoa butter can be extracted. The "beans" are the basis of chocolate, as well as Mesoamerican foods, such as mole and tejate.”
Physical properties of cocoa powder:
From “en.wikipedia.org/wiki/ Cocoa_solids”: “Natural cocoa powder has a light brown color and an extractable pH of 5.3 to 5.8. The processed (alkalized) cocoa powder is darker in color, ranging from brownish red to nearly black, with a pH from 6.8 to 8.1. The alkalization process reduces bitterness and improves solubility, which is important for beverage product applications. All of these pH values are considered safe for food use.”
“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 230 mg of caffeine and 2057 mg of theobromine per 100g, which are mostly absent from the other components of the cocoa bean. Cocoa solids also contain clovamide (N-caffeoyl-L-DOPA).”
“People around the world enjoy cocoa in many different forms, consuming more than 3 million tons of cocoa beans yearly. Every consumer has a unique taste and preferences of the end product. Once the cocoa beans have been harvested, fermented, dried and transported they are processed in several components. Processor grindings serve as the main metric for market analysis. Processing is the last phase in which consumption of the cocoa bean can be equitably compared to supply. After this step all the different components are sold across industries to many manufacturers of different types of products.”
“In general, cocoa is considered to be a rich source of antioxidants such as procyanidins and flavanoids, which may impart antiaging properties. Cocoa also contains a high level of flavonoids, specifically epicatechin, which may have beneficial effects on cardiovascular health. Cocoa is a stimulant and contains the compounds theobromine and caffeine. The beans contain between 0.1% and 0.7% caffeine, whereas dry coffee beans are about 1.2% caffeine.
The stimulant activity of cocoa comes from the compound theobromine which is less diuretic as compared to "theophylli.." found in tea. Prolonged intake of flavanol-rich cocoa has been linked to cardiovascular health benefits, though this refers to raw cocoa and to a lesser extent, dark chocolate, since flavonoids degrade during cooking and alkalizing processes. Short-term benefits in LDL cholesterol levels from dark chocolate consumption have been found. The addition of whole milk to milk chocolate reduces the overall cocoa content per ounce while increasing saturated fat levels. Although one study has concluded that milk impairs the absorption of polyphenolic flavonoids, e.g. epicatechin, a follow-up failed to find the effect.
Hollenberg and colleagues of Harvard Medical School studied the effects of cocoa and flavanols on Panama's Kuna people, who are heavy consumers of cocoa. The researchers found that the Kuna people living on the islands had significantly lower rates of heart disease and cancer compared to those on the mainland who do not drink cocoa as on the islands. It is believed that the improved blood flow after consumption of flavanol-rich cocoa may help to achieve health benefits in hearts and other organs. In particular, the benefits may extend to the brain and have important implications for learning and memory.”
“Cocoa and cacao powders may contain cadmium, a toxic heavy metal and probable carcinogen. From January 1 2019, the European Union will impose a limit for cadmium in cocoa powders of 0.6 µg per gram of cocoa powder, and 0.8 µg per gram for chocolate with >= 50% total dry cocoa solids. In Canada, a daily serving of a natural health product must contain no more than 6 µg of cadmium for an individual weighing 150 pounds (68 kg) and 3 µg for a 75 lb (34 kg) individual. While the U.S. government has not set a limit for cadmium in foods or health products, the state of California has established a maximum allowable daily level of oral cadmium exposure of 4.1 µg, and requires products containing more than this amount per daily serving to bear a warning on the label. One investigation by an independent consumer testing laboratory found that seven of nine commercially available cocoa powders and nibs selected for testing contained more than 0.3 µg of cadmium per serving gram; five of these products exceeded the proposed EU limit of 0.6 µg per gram.”