Coffee is one of the most abundant drinks in the world. Among all different types of beans, arabica coffee beans are the most extensively available, which account for 60-80% of the world's wild coffee production. As a result of the consumed amount of coffee, there is a massive amount of the spent coffee ground produced and wasted annually. Many studies showed that SCG contains some components that can be reused. Therefore, this study aimed to identify and quantify the organic groups in the SCG using different separation techniques. Five light roasted Arabica blend Coffee samples from different continents (Africa, Ethiopia; Oceania, Papua New Guinea; Asia, Indonesia, America, Guatemala, and Europe, Italy) were used to analyze the SGC relationships and differences in terms of composition. Every sample was analyzed by quintuplicate for statistical purposes using the software Rstudio statistical software.
Extraction of spent grounds was performed in a home coffee maker at 356.15°C and then oven-dried to constant mass at 333.15 K for 16h. Each dried SCG was characterized by 1HNMR, 13CNMR, and GC/MS. The brewing extraction was kept in the freezer until it was characterized by UV−vis, GC/MS, and ICP-AES.
Procedures have already been published for different carbohydrates, lipids, and phenolic fractions, while a new procedure to extract protein fractions is being developed.
Feedback by Dr. Zestos: "Good job. More detail will be required for the procedures as you now compose your methods and materials."
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