A diet free of processed foods
Convenience food is now available everywhere, from a ready meal to a packet of crisps to a bar of chocolate.
Most of us know that they are not the best options for a healthy diet, however, figures reveal that sales of ready meals make up the biggest portion of the country’s annual retail food budget. Processed foods are generally high in salt, sugar and often saturated fat. We may look in the convenience meal section of the supermarket and see a label that says ‘low fat’, and assume that it would be a healthier choice. Often that ‘low fat’ choice is very high in sugar, sweeteners, and/or salt (using these as preservatives and to enhance taste). More recently, due to the Government’s focus on sugar, chemical sweeteners are being added to many foods.
There really are very few healthy option convenience meals, although some farm shops sell ‘ready meals’ that have been home-cooked from scratch locally. Ready meals found in supermarkets, even those that look like they contain healthy ingredients, are almost always designed to have a longer shelf life than is natural (if you made a macaroni cheese, how many days would you leave it in the fridge before eating it? Some ready meals have over 12-days shelf life!). Often the ingredients have been pre-frozen or transported to the processing factory in a pre-processed state (e.g. freeze dried eggs, dehydrated potato flakes), and much of the natural nutrition will have been lost.
Common food processing methods
Blanching: Food (usually fruit or vegetables), is plunged into boiling water for a brief period and then plunged into iced water. This neutralises bacteria and destroys enzymes that spoil food, but leads to loss of water soluble nutrients.
Canning: Food is usually blanched first and some foods are sterilised at 120ºC before canning, meaning heat sensitive vitamins are lost. Brine, syrup or vegetable oil may be added and nutrients leach into this fluid which is often drained away before the food is eaten. The main nutrient losses are magnesium, potassium, folate, vitamin B1 and vitamin C.
Freezing: Freezing itself should not cause nutrient loss, but many vegetables are blanched before freezing to destroy micro-organisms, which leads to loss of B vitamins, vitamin C and potassium.
Drying: Air is passed over food to reduce water content and prevent growth of micro-organisms. Heat sensitive nutrients should be retained but commercially dried vegetables are often blanched first to give better colour and stability.
As well as losses during processing, we must also consider what is added. Approved additives are designated with an “E number” which shows it has passed safety tests and been approved for use throughout the EU. The long terms health effects of many food additives are unknown, however some have been linked to allergies and childhood hyperactivity.
Types of additives include: preservatives, antioxidants, colours, sweeteners, flavour enhancers, emulsifiers, thickeners, gelling agents, glazing agents, bulking agents, bleaching agents, anti-caking agents.
Colours: are completely unnecessary but are used to make food more attractive and replace the natural colour lost in canning. They are not allowed in certain foods e.g. baby food, tea, coffee, fresh fruit and vegetables and there are less than 20 permitted synthetic colours in the UK, as many have been found to be carcinogenic.
Preservatives: are used to increase shelf life. They may take the form of nitrates/nitrites and sulphites, which cause sensitivities in some individuals
Emulsifiers and stabilisers: Emulsifiers help mix oil and water while stabilisers stop the mixture from separating. Together they improve the texture and consistency of food. They are often found in creamy and spreadable foods like margarine, salad cream, ice cream, and spreads
Sweeteners: have been mentioned above and are becoming more and more common in a wider range of foods, as manufacturers try to appeal to demands for ‘low sugar’ products. The long term and cumulative effect of these chemicals is unclear.
Although convenience foods might seem appealing, our advice would be that it’s far better to cook in bulk using fresh ingredients and freeze your own ‘ready’ meals – it is the only way to know exactly what you are consuming.