Non-organic baby food manufacturers are allowed to use additives as processing aids or 'improvers'. Look out for ingredients such as maltodextrin, emulsifiers, hydrogenated vegetable fat, citric acid, caseinate, calcium carbonate and demineralised whey. These indicate that a food has been heavily processed.
You should also look at the label for sugar (sucrose), glucose (dextrose), lactose, fructose, maltose, meat extract, hydrolysed vegetable protein, yeast or yeast extracts, or 'flavourings' (natural or not). If a product has any of these ingredients, it may have been over-processed and, as a result, have little real taste of its own. There is no such thing as a necessary flavouring for babies - flavourings are often used to disguise poor-quality ingredients. For example, yeast extract is often used to add flavour to savoury foods that do not contain good-quality meat.
Any packaged food has to list all of its ingredients, in descending order of weight at the time the food was processed. Look out for a liquid near the top of the list, followed later on by a thickener that you wouldn't find in your own kitchen (such as modified cornflour, rice starch, gelatine, carob gum or just 'thickener'). If this is the case, the product contains more liquid than it needs and does not offer optimum nutrition.