Absinthe "the holy trinity." Many other herbs may be used as well, such as petite wormwood ("Artemisia pontica" or Roman wormwood), hyssop, melissa, star anise, angelica, peppermint, coriander, and veronica. Adding to absinthe's negative reputation in the late 19th and early 20th centuries, unscrupulous makers of the drink omitted the traditional colouring phase of production in favour of adding toxic copper salts to artificially induce a green tint. This practice may be responsible for some of the alleged toxicity historically associated with this beverage. Many modern day producers resort to similar (but non-deadly) shortcuts, including the use of artificial food colouring
What Love Is Made Of three minutes and fifty-five seconds (3:55), "What Love Is Made Of" is an uptempo dance and house track that has been described as "rave-y" and "trance-y". Its instrumentation contains the sounds of pianos and synthesizers. Jordan Sargent of "Spin" observed that it continued the musical style first introduced in Katy's 2012 extended play (EP), "Danger EP", which was "straight-forward house". Idolator's Sam Lansky compared her performance in the song to recording artist Siobhán Donaghy. Critical response to "What Love Is Made Of" was generally positive: most critics noted Katy's vocal performance and commended its sound. Siân Rowe from "NME" was