## 1 Introduction  
Beer is one of the most popular alcoholic beverages consumed worldwide. It is defined as the product of the yeast fermentation of cereal soluble sugar, usually flavored with hops [1]. Nowadays, the craft beer industry constitutes a growing economic sector, as consumers perceive artisanal beers as a higher quality product, thanks to the several varieties of flavors they can present, different from those found in commercial beers [2, 3]. Along with factors related to the purchasing process, consumer preferences are affected by the beer sensory characters [4], particularly aroma, flavor, mouthfeel and appearance, determined by both the brewing process and the ingredients [5, 6]. The beer flavors and aromas, resulting from a complex balance of several volatile compounds rather than a single constituent [7, 8], are ascribed to the used raw materials and to the brewing process. Undoubtedly, hop (_Humulus lputhus_ L.) is the main contributor to the aroma of the final product [9], being responsible for the peculiar and appreciated happy scents, which are directly related to the volatile composition of its essential oil (EO) [10]. However, the aroma characters of the other raw starting materials used in the brewing process influence the final product bouquet, as well, as evidenced by [PERSON] et al. (2020), whose study reported the flavoring of a beer with hemp flowers [7]. Along with the volatile organic compounds (VOCs), polyphenols play a crucial role in consumer preferences. These secondary metabolites decisively influence the sensorial quality of the beer, contributing also to its stringency, body and color [2; 6]. Astringency and body are two significant attributes of the mouthfeel, defined also by other parameters which together concur to modify the release of the volatile compounds, influencing the whole sensorial character of the final product [11; 12]. Finally, the color is an important visual feature of the beer, as well as of the other foods and drinks, because it can influence the consumers' experience determining expectations on taste and flavor of the product [13]. The color depends on both the type of employed grains and the processes they under-went during the brewing: mashing and wort boiling are key phases in the color formation, since they determine several chemical modifications, including the caramelization of sugars, oxidation of polyphenols and the Maillard reaction [1; 14], which is of the utmost importance in the flavor development [9]. Therefore, each sensory character of the beer is strictly connected to each other, and together they contribute to determining the organoleptic profile of the final product [15]. In recent decades, an increasing interest to propose new flavored beers has been noticed. _Hibiscus rosa-sinensis_ L. is an appropriate candidate to achieve this goal, as its red flowers are widely used in traditional food as a flavoring agent [14], as well as in local medicine for their antipyretic, analgesic, anti-asthmatic and anti-inflammatory activities [15; 16; 17] due to its secondary metabolites content [16]. _H. rosa-sinensis_, also known as \"Chinese hibiscus\" or \"tropical hibiscus\" [15], is a perennial shrub belonging to the Malvacae family, typical of tropical areas [15; 16]. It is a plant of considerable commercial importance due to its presence in several herbal remedies [16]. Although _H. rosa-sinensis_ is harvested for different plant parts, flowers are the most employed ones. Among the different bioactive compounds contained in the flowers, polyphenol compounds are of the utmost importance for their antioxidant properties [18]. Polypphenols, in fact, are key components in the food industry and are widely exploited to maintain oxidative stability [19; 20] as they work as scavengers of free radicals and as natural metal chelators [19], contributing to several sensorial characters and prolonging products' shelf-life [21; 22]. The present study aimed to evaluate the volatile chemical composition and the sensorial properties of a beer flavored with _H.