Roku is produced in the "Liquor Atelier", the specialised craft distillery for Suntory spirits and liquor. The Atelier owns four distinct types of pot stills and, in a process unique to Roku, the botanicals are distilled separately according to each feature of botanicals to extract the best flavour and maintain their individual characteristics. For instance, the delicate scent of cherry blossom is drawn out through vacuum distillation in stainless pot stills, whereas the deep flavour of yuzu is achieved by distillation in copper pot stills. Roku's complex, yet harmonious flavor is the result of the unique Japanese sensitivity captured in the blending of the carefully crafted extracts of the 14 botanicals.