I understand your frustration and applaud your not wanting to spank your son. Let's try to put this into the context of his development.
It's perfectly normal for a toddler to become quite frustrated. Since he doesn't have the verbal skills to express himself in words, he'll show his frustration through his actions. That's why he bites, pinches, and hits. It has nothing to do with "a bad temper"; it's simply a sign that he's feeling overwhelmed. This will get better with time.
Sometimes you will be able to prevent the problem simply by distracting him. For example, if he's frustrated by a toy he's playing with, help him play with a different toy or pick him up for a minute and sing him a song.
Much effective discipline with infants and toddlers is best done through environmental control. If you don't want him breaking your favorite porcelain figurine, put it well out of his reach. That way you don't have to count on his understanding "No!"
Finally, remember that he's only 19 months old. He's not acting out of spite or malice, even though it may sometimes feel that way. He doesn't yet understand the consequences of his behaviors.