A bière de coupage is a blend of old (barrel aged) and young (stainless steel fresh) beers blended together and bottle conditioned. Why do this? To give the beer a wide array of flavours and textures that if it was just one or the other wouldn’t be as delicious. The older barrel aged beer gives acid, and rich/ripe fruit aromas (mango). The young beer gives bitterness, and fresh primary fruit aromas (pineapple).