Coffee silverskin - new and natural alternative to generating selected bioactive compounds

Kawa jest jednym z najczęściej spożywanych napojów na świecie. W wyniku ciągle zwiększającej się konsumpcji kawy, przemysł kawowy wytwarza coraz większe ilości produktów odpadowych. Łuska srebrzysta stanowi jedyny produkt uboczny procesu prażenia kawy. Zarówno w Polsce, jak i w innych krajach zajmujących się prażeniem kawy, otrzymywane są znaczące ilości tego odpadu. Łuska srebrzysta oraz ziarno kawy są w bezpośrednim kontakcie ze sobą, w związku z czym mogą zawierać podobne związki bioaktywne, wykazujące zbliżone wielokierunkowe działanie biologiczne. W opracowaniu przedstawiono informacje dotyczące wybranych związków bioaktywnych występujących w ziarnach kawy i kawowej łusce srebrzystej, ich właściwości i potencjalnego wpływu na organizm ludzki oraz stosowanych na chwilę obecną metod ekstrakcji.Coffee is one of the most popular and widely consumed beverages around the world, being highly appreciated for its stimulating and unique sensory properties. With the continuous growth of coffee consumption rate in either importing, or exporting countries, coffee production has increased annually. As a consequence of this, large amounts of residues are generated during coffee fruit processing. Coffee silverskin is the only by-product produced during roasting process and can be collected in large quantities from roasting factories. But this residue may be a great environmental hazard if haphazardly discharged into the environment. Coffee silverskin is a thin tegument of the outer layer of green coffee beans. Coffee silverskin and coffee beans are in direct contact with each other and because of that, they may contain similar bioactive compounds, which can show similar multidirectional biological activity. It is well known, that coffee is a rich source of bioactive compounds, such as caffeine, chlorogenic acids and many others. The extensive studies have been conducted on the coffee chemical composition, as well as on its potential biological properties. In recent years, the bioactive compounds present in coffee and coffee by-products have gained considerable attention. Many studies suggest that diets rich in these compounds promote numerous benefits for human health and well-being. Antioxidants recovered from coffee silverskin may find numerous applications in food and pharmaceutical industry. Nowadays, there is an urgent need to avoid the use of synthetic antioxidants (e.g. butylated hydroxyanisole or butylated hydroxytoluene) in food products. Reusing of coffee silverskin to obtain bioactive compounds appears to be a very promising, natural, low-cost alternative to synthetic antioxidants. Based on aforementioned concerns, it is important to develop efficient method to extract bioactive compounds from coffee silverskin. Recovering bioactive compounds from coffee silverskin can be done by different techniques and conditions. Several factors influence the efficiency of extraction process. Presently, the most common method of antioxidants extraction is solid-liquid extraction using organic solvent. In this sense, the aim of this paper was to compile information about chosen bioactive compounds present in coffee beans and coffee silverskin, their properties and potential effect on human health as well as commonly used extraction methods