This probably isn't what you want to hear - but it sounds like he's just not ready. My 1st child wasn't interested in solid food until closer to 8 months, and even at 1 year old he wouldn't take anything with chunks. Then, one day around 14 months, he just started eating anything we put in front of him and he's a great eater to this day (4 years old).
My 2nd child, on the other hand, loved cereal starting at 6 months and already loves to eat pasta, cheerios, etc, at 9 months. Totally different from the 1st child.
What I've learned from this is that every child has his own schedule, and he'll let you know when he's ready to eat solid food. Offer something every now and then, and don't try to force it, because you'll turn it into a battle of wills/control issue, and you don't want that!