When can a baby try eating instant food like noodles and canned soups or processed fruits?

It's best to keep those foods away from baby for as long as possible but some of my mommy friends do give their kids processed foods and it's usually when they are in kindergarten (around 5-6). They say that since the kids are going to start primary school in a couple of years, there is no point keeping those foods from them. They will caution their child from eating too much of these foods though.