This may explain why older infants reject bitter-tasting foods like some green vegetables. These foods would need to be introduced again and again so that eventually they may be tolerated and even enjoyed. By term, the fetus is swallowing amniotic fluid and has been exposed to glucose, amino acids, lactic acids and salts. Infants seem to detect and retain information about the chemical characteristics of their environment. When older, infants are able to respond differently to scented and unscented objects, dependent upon the amount of experience with that odour.
Human milk is rich in flavours dependent upon the foods and spices eaten by the mother.
Breastfed infants can learn about the flavour of the food of their culture long before solids are introduced . Infants feed longer and more ove rall when milk is flavoured with either garlic or vanilla . Fo rmula fed infants also responded by increasing their intake when vanilla was added to the formula. However, the response diminished after repeated exposures. Perhaps the flavour became less arousing after exposure to it.