Humans would indeed make a good food source on deep space missions, thats why there are cattle mutilations, they are testing the meat quality of the planet. Humans = t-bone.

But seriously to think we are alone is a foolish venture.
Any species that has mastered interstellar space travel is more scientifically minded then they would be a violent race.thats why they wanna stick a space probe in your anus.(roflmao, damn i am baked) If they were a violent race they would kill themselves off with wars and never progress on a universal evolutionary scale. ( sound familiar ? ) humans now possess the engine techknowlogy to make it to the nearest star. It would only take 48 years.

Source: the science channel.