## 1 Introduction  
Agricultural production leads to the accumulation of agro-food wastes and by-products. These wastes can be reused as they are a source of bioactive compounds such as phenolics that can be extracted by several conventional and non-conventional techniques.  
Coffee is one of the most consumed products in the word; world coffee production for 2018/19 was estimated to be about 170,937,000 bags (60 kg/bag) [1]. For the preparation of coffee, coffee grounds must be released from the coffee cherry. During this step, many parts of the cherry are thrown away. Coffee pulp is the main by-product; other by-products of coffee production include husks, silver skin, and spent waste coffee. It is estimated that around one ton of coffee pulp is produced during the manufacture of two tons of coffee [2]. Coffee pulp is rich in cellulose, hemicellulose, phenolic compounds, and caffeine [3]. Chlorogenic acid is the main phenolic compound in coffee pulp contributing to the sensory attributes of coffee [4, 5]. Specifically, it is responsible for the bitter, sour, and astringency tastes. During roasting, chlorogenic acid turns into lactones and contributes to the bitter taste of the brew [6, 7]. Caffeine is another significant compound in coffee, contributing 10-30% of the final bitter taste of the brew [8].  
Solid-liquid extraction is the most common technique for the extraction of polyphenols. The solvent penetrates into the plant tissue and contributes to the dilution of the bioactive compounds [9, 10].  
The nature of solvent, the temperature, the volume of the solvent and the time of extraction can control the final yield of the process. A novel approach in extraction processes is the development of environmentally-friendly systems, such as deep eutectic solvents and solutions of cyclodextrins [9]. Cyclodextrins are cyclic oligosaccharides which are composed of six to eight glucopyranose units. Cyclodextrin has a hydrophobic cavity and a hydrophilic surface. This structure may be used as a vessel for the extraction of hydrophobic compounds that create an inclusion complex with cyclodextrin [11]. Recent studies have investigated the extraction ability of cyclodextrin solutions and reported efficiencies that were adequate, and in some cases even higher than those obtained with conventional solvents [12; 13; 14]. Moreover, cyclodextrins can be used as masking agents. Based on the characteristic molecular structure of cyclodext, they can capture specific compounds and prevent the interaction with taste receptors [15]. Several scientific reports have investigated the creation of complexes between cyclodext and the bitter compounds in coffee, such as chlorogenic acid and caffeine [16; 17; 18].  
Coffee brewing is a solid-liquid extraction which affects the quality and flavor of the drink. Commercial coffee vendors have invested in cold extraction, suggesting that a cold brew coffee possesses a different sensory profile than a conventionally brewed coffee [19]. Due to the huge coffee consumption, large amounts of by-products are generated in the coffee industry. The current study suggests that by-products from the coffee industry can be utilized as potential functional ingredients. Coffee pulp valorization could lead to the development of innovative brews containing substantial amounts of functional components, such as caffeine and chlorogenic acid, which may lead to health benefits in drinkers [20], while demonstrating unique and appealing sensory properties. However, coffee pulp has not been investigated for its sensory properties.  
The purpose of this study was the optimization of the extraction process of bioactives from coffee pulp using eco-friendly \(\beta\)-cyclodextrinrin solutions. The optimization process was based on a central composite design and the responses considered were the antiradical activity and the caffeine content. Moreover, the sensory profile of the brews obtained from coffee pulp was examined.