Kopi Luwak civets choose which cherries to eat – i.e. those that are most ripe and flawless. Digestive mechanisms may improve the flavor profile of the coffee beans that have been eaten. The civet eats the cherries for the fleshy pulp, then in the digestive tract, fermentation occurs. The civet's protease enzymes seep into the beans, making shorter peptides and more free amino acids. Early production began when beans were gathered in the wild from where a civet would defecate as a means to mark its territory. On farms, civets are either caged or allowed to roam within defined boundaries. Coffee berries
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