The taste buds are developing like every other things. We need to train them. This training cannot be started early enough. A fetus learns from the 5th month of pregnancy to know what is salty, sweet, bitter etc. Although the fetus has its own genes which say what it likes or not, the taste can be trained. What a child will like or not starts in the womb of the mother. The nutrition of the mother influences the fetus more than we think. All she eats gives the amniotic fluid a specific taste. It is said that the fetus will drink more of it the sweeter it is.
But even if the new born child has its preferences, the learning process is not yet completed. From now the child has to explore the maximum different tastes as possible. Always if the child eats something which is new to it, it might not like it, but do not stop to try and give it the same food again. The child needs to learn to like the different tastes, this can only be made with eating and eating it again.
The development of the taste buds is associated with the location where the people live. A african child will learn to appreciate other food than an european child.
The more different types of food the child knows and appreciates it, the higher is the chance that it does not refuse it when it will be a little bit bigger. Children of about two years age do refuse a lot of food, if they do not know it. To prevent this, the child must know many different types of food before reaching this age. But you cannot ensure that the child will eat everything. This is the normal development of a child that it refuses food. But do not be discouraged and try to give the food again and again.
And by the way, the development of the taste buds does not end in childhood! All of us are still developing and we can learn to like food which we thought we do not like.