Pureed products, canned food items, are most popular in the West. But a UK expert has warned that they could prove harmful to children.
Purιe is a general term for food, usually vegetables or legumes, that have been ground, pressed, and/or strained to the consistency of a soft paste or thick liquid.
The term comes from French, where it meant purified or refined.
Infants should be fed exclusively on breast or formula milk for the first six months, then weaned onto solids. If not, it is feared they could lose out on vital nutrients derived from breast milk, which protect against common infections and allergies, says Gill Rapley, deputy director of UNICEF UK's Baby Friendly Initiative.
Spoon-feeding them pureed products could also delay their chewing ability, cause them to become fussy eaters and increase the likelihood of constipation. The warning comes after research backed by the World Health Organisation (WHO) showed that feeding babies pureed food was unnatural and unnecessary. Four out of five babies aged between four and twenty months now rely on the tinned and jarred products, many of which are organic or made with fresh local ingredients to increase their appeal to parents.
The pureed baby food industry in the UK is now worth more than £450 million - compared with £191 million in 1989. Mrs Rapley said: "Parents often think that their babies need something more than milk when they get to four months or so. "But scientists and government advisors now agree that this isn't the case.
"In 2002, the World Health Organisation backed-up research that found breast or formula milk provided all the nutrition a baby needs up to the age of six months. "Any other food during their first six months dilutes the nutritional value of the milk and might even be harmful to the baby's health.
"After six months, babies should still be breast fed but they should also be given solids - proper pieces of meat and vegetables that they can chew and suck. There is no need for pureed food at all."
While working as a health visitor for 25 years, Mrs Rapley also undertook her own UK-based research into the feeding habits of infants.
She found that babies who were fed on solids after six months (pieces of meat, vegetables and fruit that aren't mashed) developed better chewing skills than those who were fed pureed food. They also developed better hand control as they were more likely to feed themselves than be spoon-fed by parents.
Infants who had been fed pureed food before six months often didn't take easily to solids as they were used to eating food where individual tastes and textures were disguised. But babies who were weaned straight from milk onto solids proved to be less fussy about what they ate.
Those who were fed pureed food by their parents were also more likely to become constipated - because they could not control how much food they ate or how long they chewed it. But Roger Clarke, director general of the Infant and Dietetic Foods Associations (IDFA), which represents manufacturers Heinz, Nestle and Boots, has dismissed her warnings.
He said: "This is new research and we need to look at it carefully.
"But the age at which solids are introduced depends on the nutritional and developmental needs of individual infants. "Generations of parents have relied on these recipes to provide safe nutrition with a wide variety of textures - from purees that are easy to suck straight from a spoon to soft lumps that encourage chewing."