From raw ingredients to foodsWhile some foods can be eaten raw (like most fruits and some vegetables), most foods need to be processed in some way to ensure safety and digestibility, and to improve colour, flavour or texture, to meet consumer expectations. The most basic definition of food processing is “a variety of operations by which raw foodstuffs are made suitable for consumption, cooking, or storage”. Hence, you could consider washing, peeling, slicing, juicing, and removing inedible parts, to be forms of processing. Legislation defines “food processing” as actions that substantially change the initial product, including heating, smoking, curing, maturing, drying, marinating, extraction, extrusion.1 How does food processing affect nutritional value?Simple procedures like washing, cutting and packaging of fresh vegetables have little effect on their nutritional quality. Heating and boiling can reduce vitamin content (particularly water-soluble vitamins such as vitamin C, for example up to 40% of vitamin C can be lost from boiling peeled potatoes2), which varies with heating time and temperature. The process of blanching or boiling vegetables for a few minutes, followed by freezing, drying or canning, retains vitamins and minerals. Refined grains like white pasta, rice and bread, contain a lower amount of fibre and of vitamins and minerals than their whole grain counterparts; unless these are added back after milling (by the process of enrichment). In other cases, processing can release nutrients and make them more readily available for our bodies to use.
