Determination of antioxidant properties and their bioaccessibilities of coffee beans grown in different countries

Coffee, which has been consumed as an enjoyable drink for centuries, is a very important consumption material that contains different production and consumption relations. After oil on a global scale, coffee is the most valuable commercial commodity of the world economic markets. Coffee is an important product of the Rubiaceae family and the Cinchonoideae subfamily. Coffee beans are produced from the Coffea L. plant with more than 80 species. However, only two of these species are commercially important worldwide. In general, 70% of the coffee bean trade is covered by Coffea arabica (Arabika) and 25% by Coffea canephora (Robusta). Coffee is known to have protective effects on many diseases such as cancer, type II diabetes, Parkinson's disease and cardiovascular disorders due to its bioactive components. In this study, it is aimed to determine the antioxidant properties and bioaccessibility of coffee beans of Arabika and Robusto varieties grown in different countries so that they are green and roasted. Also, the assays of total phenols and antioxidant capacity were prepared two different extraction (extractable and hydrolysable fraction) methods and total polyphenol content was analysed using Folin–Ciocalteau assay and antioxidant capacities were used 3 different (CUPRAC, ABTS, FRAP) methods. In addition, for the determination of bioaccessibility, coffee beans were processed by an in vitro digestive enzymatic extraction that mimics the conditions in the gastrointestinal tract. As a result, antioxidative differences between coffee bean varieties were determined and effects of roasting of coffee beans were revealed.