Babies start eating weaning food at around five months old. After one year, slowly the food is changed from milk (breast feeding) to solid food.There are a lot of snacks (wakodo and so on )for babies from around five months old such as Senbei (rice crackers) and egg bolos (small round cookies).
However, the recommended period for eating snacks is when the baby is nine or ten months old and starts chewing and eats three meals a day in the morning, at noon and in the evening. Initially, the basic amount is some drinks like juice plus two pieces of Senbei(wakodo, etc)as supplement. The amount should be to the extent till the baby enjoys.