Why have my 10 month old baby's eating habits changed?

He has just got over a sickness/diarrhoea viral bug. He has always been a very good eater. Last week when he was ill he projectile vomited whilst we were out all over the floor and table we were dining at. Obviously he was off food for a few days. He is now happy to eat his morning cereal and his fromage frais puddings but as for his jars (which we are trying to get him off) he is having tantrums, refusing to eat and crying hysterically. If i do mange to get some in his mouth he gags after each mouthful. Could he be frightened of lumpy food now or does he ociate his vomiting last week with his jarred food which went everywhere.