Chili flakes are crushed, coarsely ground chili peppers. Some varieties are processed without kernels or seeds to improve the taste, but not make the dish very spicy. Other varieties, on the other hand, contain the seeds and are accordingly spicier.
From Wikipedia: “Capsicum (/ˈkæpsɪkəm/; also known as peppers) is a genus of flowering plants in the nightshade family Solanaceae. Its species are native to the Americas, where they have been cultivated for thousands of years. Following the Columbian Exchange, it has become cultivated worldwide, and it has also become a key element in many cuisines. In addition to use as spices and food vegetables, Capsicum species have also been used as medicines and lachrymatory agents.”
“In 2013, global production of both green and dried chili pepper was 34.6 million tonnes, with 47% of output coming from China alone. India was the top producer of dry peppers, producing 1.4 million tonnes.”
Nutrition of peppers:
“Peppers are highly nutritious. They have more Vitamin C than an orange, and a typical bell pepper contains more than 100% of the daily recommended value for Vitamin C. They also have relatively high amounts of Vitamin B6. Fresh fruit is 94% water. Dried pepper fruit has a much different nutritional value due to the dehydration and concentration of vitamins and minerals.”
Information about chili flakes:
From “en.wikipedia.org/wiki/ Crushed_red_pepper”: “Crushed red pepper (CRP) or red pepper flakes (RPF) is a condiment consisting of dried and crushed (as opposed to ground) red chili peppers.
This condiment is most often produced from cayenne-type peppers, although commercial producers may use a variety of different cultivars, usually within the 30,000–50,000 Scoville unit range. ...
Crushed red pepper shakers have become as standard as salt and pepper on tables at Italian style restaurants and especially pizza parlors in the United States. Often there is a high ratio of seeds, which some people believe intensifies the heat of this flavorful condiment. Crushed red pepper is used by food manufacturers in pickling blends, chowders, spaghetti sauce, pizza sauce, soups and sausage.
Crushed red pepper in Turkey, served as a common condiment with very few seeds, is known as pul biber and "paprika" in English. One specially prepared variety of it is the Urfa pul biber.”
Preparing chili oil:
If you would like to make chili oil, here is a simple recipe: Place one tablespoon of chili flakes and 250 ml oil of your choice in a glass container, close tightly, and let stand for a few days. Since capsaicin is fat-soluble, with time it will diffuse from the chili flakes into the surrounding oil. As a result, this is a great way to make chili oil.
Handling products containing capsaicin:
As with other products that contain capsaicin, you should make sure to wash your hands well after using and avoid contact with mucous membranes.
Translation from: “de.wikipedia.org/wiki/ Capsaicin“: “Since capsaicin isn’t water soluble, it is essential that you wash your hands with oil or alcohol. This is the only way to completely remove the capsaicin from your hands. With hot varieties, it is a good idea to wear plastic gloves. And with extremely hot varieties, even very small amounts that come into contact with the eyes, mucous membranes, or skin can cause skin irritations —which, in some cases, can be serious.”