Lab/Rot 11 Months (TEMPER PROBLEMS)

Hi all, I have a lab/rotty about 11 months old. Very healthy dog. He
is house trained and knows a few tricks. One of his big problems is
when we give him a rawhide or big bone or he some how gets a peice of
trash.....if he is biting on his bone doing the usual and we try to
pet him/look at him/or go near him...he has a visssscious growl and is
very scary...sometimes if you push it too much he'll go at you and
explode w/ anger...a few times he has bit us (IT HURT) But i don't
know if this is normal or we have trained him wrong or needs to be
trained again. Hes 11 months, so maybe its too late??? This is a
chronic problem and always seems to happen when he has a
bone/rawhide/peice of trash. We can't touch him or pet him.
Sometimes if he flips out and goes at ya we have to spray him with the
apple vinegar, thats the only way to protect yourself sometimes. In
all other situatoins he is a very nice and lovely dog.

Comments.....Suggestions are much appreciated!!

Thank You.