Hitman: Blood Money

Simply take out a sryinge and then press r1 when the crosshairs are on the sausage.

In New Life, pull out whatever syringe type your going to use; sedative or poison. Walk up to whatever food it is, like the donuts in the back of the caterer van, and position the crosshairs on it so that they turn red, then just simply press R1, but be very careful, people don't like it when they see you poisoning things.

You can Do what the other two before said before me or Pick up the item then use triangle to drop it then crouch aim and poison

I usually take the sausage,wine,to a remote location place it on a table or floor aim the crosshairs at the sausage,rim of the bottle,etc then wait for someone to die of Uthanasia and get what i can get such as weapons,clothing,objects needed to pass the level,etc...or if i want to scare the crap outta people put a bomb close to the object >:). Does this answer the question?

Equip the syringe poison then point the crosshair on any food that can be eaten by AI,when the crosshair turns to red,you can poison the food