By: Erika Henson
The process of preserving food with sulphur dioxide is intended to provide a longer shelf life, kill harmful bacteria that might grow on vegetation and foods, and help food products maintain a certain visual appearance; however, it's also considered one of the top six air pollutants. Sulphur dioxide occurs naturally in volcanic gases, in some dissolved waters of warm springs, and is a result of coal, fuel, and gas combustion. It is not confined to a specific area as it travels long distances in a short amount of time. It is produced industrially as a bleach alternative, a reducing agent, and for sulfites (preservation). As it has no role in humans or mammalian biology, when introduced it inhibits specific nerve signals, restricts lung performance, and is a direct allergen - over 65% of asthmatic children sensitive to SO2 (World Health Organization, 1999), and negatively affects over 70% of children with behavioral problems.
Sulphur dioxide is used as a common sulphite that is added to dried fruit, fruit juices, fruit, breakfast cereals, and many processed snacks including cookies, soft drinks, meat, cereal bars, muesli bars, yogurt, ice cream, candy, frozen french fries, bread, margarine, and gluten-free flours. It is also used in the process of making wine, even wines that say "no sulphites," and is found in ingredients like vinegar, corn syrup, corn starch, maltodextrin, potato starch and flakes, beet sugar, bottled lemon juice flavor and dressings, and glucose syrup. Checking food labels for sulphites, sulphur dioxide, and numbers in the range E220-228 is helpful; however, companies are only required to list sulphites as an ingredient when the amount is above 10 mg/liter or 10 ppm. This can be confusing when the specific ingredients used contain sulphites even though little to no sulphites are added independently.
Sulphur dioxide is used as a preservative because it works as an antimicrobial preventing the growth of bacteria, mold, and fungus; an antioxidant preventing rancidity; and as a chemical that attacks enzymes that cause discoloration, ripening, and rotting, usually in fruits after harvest. Through the process of plasmolysis plant and food cells are altered by contraction and separation through the loss of water. Sulphite preservation causes these cells to die: instead of being transferred quickly to a water solution, foods are packaged and sit on shelves for an unspecified amount of time before being eaten. In order for our digestion to work properly we need good bacteria and enzymes found naturally in fruits and vegetables to be available to aid our bodies in breaking down necessary nutrients, and living cells so that we supply our body with nutrients, use our energy and healing capacities for more creative purposes, rather than stealing energy for digestion. Aside from any counterindications of using sulphur dioxide or any other sulphite preservative in food, if air and water can no longer break down certain food ingredients, how will our bodies manage to extract and utilize any nutrients during digestion, let alone properly digest it?
Sulphur dioxide is still being used as a food preservative in many common snack foods despite being one of the top two air pollutants in urban areas, a corrosive gas, a primary cause of haze and acid rain, and a cause of respiration problems, lung disease, early death (due to a thiamine deficiency), documented water and plant damage, cardiovascular disease, blood toxication, developmetal toxication, gastro-intestinal and liver disease, neurological disturbances, irritable bowel syndrom, behavior disturbances, skin rashes, asthma, folic acid deficiency, as well as a nose and ear irritant. During the 1970's and 1980's over one hundred deaths were attributed to the addition of sulphur dioxide in foods including meat with twelve deaths occurring as a result of restaurants spraying salad bars with this poisonous gas. Since 1959 there has been a ban on preserving meat with sulphur dioxide and since these restaurant deaths there is a ban on spraying salad bars as well.
There are less toxic alternatives to sulphur dioxide and other common chemical preservatives including rosemary extract which is an antioxidant, sea salt, and homemade vinegar. However, our bodies already have enough work to do within the environments we choose to live, so eating straight from nature or as close to nature as possible stills seems most nourishing and the easiest to digest. Eating more raw and living foods, getting rid of processed foods in the diet, as well as buying dried nuts and snack fruits from companies known for being preservative-free (or making your own in a dehydrator) are the best ways to nourish your body. Asthmatics, people with sensitivities and allergies, as well as people on more natural diets will feel and have more natural capacity for healing and sustaining energy by paying attention to food labels and researching the companies supplying healthier snack alternatives like dried fruit, nuts and seeds, fruit juices, and gluten-free products.
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