Coffee bean rain is needed in the beginning of the season when the fruit is developing and less later in the season as it ripens. When the fruit is ripe, it is almost always handpicked, using either "selective picking", where only the ripe fruit is removed, or "strip-picking", where all of the fruit is removed from a limb all at once. This selective picking gives the growers reason to give their coffee a certain specification called "operation cherry red" (OCR). In rare circumstances, the Asian palm civet eats coffee berries and excretes the beans. These beans are called "kopi luwak", and can
Cellular waste product as well as by cells called anaerobes that selectively perform anaerobic respiration even in the presence of oxygen. In anaerobic respiration, weak oxidants like sulfate and nitrate serve as oxidants in the place of oxygen. Generally, in anaerobic respiration sugars are broken down into carbon dioxide and other waste products that are dictated by the oxidant the cell uses. Whereas in aerobic respiration the oxidant is always oxygen, in anaerobic respiration it varies. Each oxidant produces a different waste product, such as nitrite, succinate, sulfide, methane, and acetate. Anaerobic respiration is correspondingly less efficient than aerobic respiration. In the absence