## 1 Introduction  
Coffee is made from the dried, ripe seeds of various Coffea species, primarily _Coffea arabica_ (commonly known as Arabica), _C. canophora_ (Robusta), _C. liberica_, and others from the Rubiaceae family. It is the third most consumed beverage in the world, following water and tea, with an estimated 11.8 million tons consumed globally each year [1]. Coffee contains a wide range of biologically active and aromatic compounds. These include caffeine (1-2%), a central nervous system stimulant; chlorogenic acid derivatives (5-7%), which are believed to have antioxidant properties; vitamin B\({}_{3}\) (0.25-1%); as well as volatile oils and tannins that contribute to coffee's distinctive aroma and flavor [2]. There are several traditional methods for processing coffee, most notably the dry (or natural) method, the wet method, and hybrid approaches often referred to as semi-dry, semi-wet, or, more recently, the honey process. In addition, newer techniques such as anaerobic fermentation and carbonic maceration are beginning to see commercial use. Another relatively recent and popular method involves animals--especially civets--ingesting the coffee cherries. The beans pass through the animal's digestive system, are collected from the excreta, and then processed into what is commonly known as \"dung coffee\" [3]. It is widely recognized that specific coffee processing methods significantly affect the quality, chemical composition, and biological activity of the final beverage. This is particularly evident in processes that involve animal digestion. For instance, civet coffee typically contains lower levels of caffeine but may be richer in certain aromatic compounds, such as guaiacol, pyrazines, and furans [4], as well as organic acids like citric and malic acid. These changes are attributed to the action of microorganisms [5] and digestive enzymes in the civet's gastrointestinal tract. These agents help break down complex molecules into simpler ones, such as amino acids and sugars, which can undergo further transformation during roasting through the Maillard reaction--resulting in elevated levels of compounds like pyrazines [4,6]. More recently, coffee produced using other animals, such as elephants, jacu birds, and monkeys, has entered the global specialty coffee market. Among these, elephant coffee has attracted particular interest due to its distinctive production process and exceptionally high price, which can reach up to USD 4000 per kilogram. However, to date, there has been little to no research describing how this method of processing affects the coffee's final chemical composition or biological activity. As with civet coffee, it is reasonable to assume that exposure to the elephant's gut microflora and digestive enzymes may induce specific chemical changes in the beans. Identifying these unique compounds could serve as a reliable means of authenticating elephant coffee--an important step given its high market value and vulnerability to adulteration. Both targeted and untargeted analytical techniques are employed to detect coffee fraud. Specific biomarkers, such as diterpenes, phenolic compounds, and fatty acids, are commonly used to differentiate between coffee species and to identify common adulterants like maize, chicory, or barley. Untargeted metabolomic analyses, particularly of volatile compounds and other metabolites, can also help determine the geographical origin of coffee [7]. However, there remains a lack of sufficient data on key metabolites, along with an absence of standardized methods for verifying the authenticity of coffee processing techniques. This gap is largely due to the limited availability of comprehensive datasets and the complexity and variability of factors that influence coffee cultivation and roasting [8,9].