Question

The directions on a Jell-O box state that raw fruits or vegetables can be added to the Jell-O just before full solidification. However, the directions specifically state that pineapple must be cooked before adding to gelatin. Gelatin is processed collagen and can be used to thicken foods, such as Jell-O. Pineapples are part of the bromeliad family and contain a protease called bromelain. Using this information, explain why the Jell-O box has explicit instructions about cooking pineapple before adding it to Jell-O.

Answer 1

The chemical called bromelain in pineapple contains two enzymes that can digest proteins(proteases). Collagen, is a protein that makes a link to give a structure for jell O to take a shape by converting liquid  state to solid gel. So if pineapple is added to jell-O, the enzymes links as fast as they form, so the gelatin doesn't  sets up. Here the collagen formation is prevented by the protease activity of the enzyme. So if the pineapple is heated before adding to Jell-O or gelatin is the best way to prevent this, it is because the bromelain gets inactivated due to heat.