The system involves a reusable water bottle to which you attach a scent pod that releases flavour into your mouth as you drink. It is important to get the taste in your mouth rather than just sniffing the scent through your nostrils. You can get almost any scent from lemon to coffee — although the strongly fruity flavours like cherry and other popular flavour-directions like cola are the customers’ favourites, says [Lena] Jüngst.

— Munich-based startup Air Up uses retronasal olfaction to flavor plain water; read more in Pepsi backs German startup that flavours drinks using just scented air at Sifted.