Right, so I'll break this down into the two parts- the Spell part and the Love part.
Yes, spells can be performed that way. Chanting to produce an effect is called a Mantra, and isn't actually as common as popular culture would have you believe. Most speech-based spells are more similar to Prayers, plus psychodrama.
It is absolutely doable to work a spell into a consumable substance, so the energy is released as it is digested. Many people specialise in this.
As for the love part, just where do you imagine that Magick comes from? Where do you imagine that energy comes from? It is within you, and her, and everyone else, all the time. The whole universe in fact. And there is nothing in this world so capable of directing and contorting that energy as human will.
I won't tell you how it's immoral to try and bend the will of another- I'm telling you flat out that it won't work. Their will is as strong as yours, as far as the universe is concerned, and their kingdom is as great. You can cast the spell and send that energy out, but if it isn't already her will to love you, the spell will crash against her like waves on an unyielding cliff.
Do yourself a service and talk to her like a fellow human being and global citizen.