I have experience with this. There is probably no cause for concern as most babies who refuse solids just aren't ready for them yet. However, some children do have hypersitivity in their mouths or delays in oral motor skills that can result in an aversion. (I'm not sure that this is really due to not introducing solids at a particular time though.) My DS was seven months when we first introduced solids, and he was not interested. I assumed he just wasn't ready and would eat them when he was. I also assumed that if he were hungry he would eat, but for him this was not true. He started wanting to nurse constantly and completely stopped gaining weight after one year (he gained no weight at all from 12 months to 21 months). Then he stopped growing taller as well. At 21 months we finally decided intervention was needed and started a program recommended by therapists. When he started eating, he immediately started growing again. (Many babies do continue to thrive on breastmilk alone after one year, but my supply dropped for some reason and was not enough even though we nursed on demand day and night.)
For my DS there were other signs of a problem besides just not being interested in solids. Does your baby put toys or other objects in his mouth? (my DS never did). How does he do with tooth brushing or you putting your fingers in his mouth to look at teeth? (My DS screamed for any of this). On the rare occasion that DS put a bit of cheerio in his mouth or I put some pureed food in his mouth, he appeared to have no idea what to do with it. He made no attempt to chew it, move it around his mouth, swallow, or spit it out. He would just sit with his mouth hanging open and cry until it desolved or we were able to remove it for him.
So, I'd look for these other signs of a problem, but if they aren't present your baby is probably fine and will probably eat when ready. I'd also recommend giving food frequently to play with even if baby isn't interested in eating it. This gives more opportunities to get used to the smell and texture and to experiment with it.
I hope this information is helpful.