Thursday, November 29, 2012

From Lab to Lunch: Chemicals They Call Food



The other day I was snacking on some bright orange “nacho” flavored tortilla chips when I decided to do something very stupid. I flipped the bag over and read the ingredient list. Given the color, I wasn’t expecting to find nature, distilled, but the double-digit list of ingredients, many of which I hadn’t seen since working in a lab, was still disconcerting. In fact, some of the chemicals were the same ones that drove me out of the lab. (You can only read “extreme neurotoxin” and “mutagenic” so many times before pondering a career change.) What were they doing in my chips?
A tortilla chip seems so simple (corn, oil, salt) but the intersection of synthetic chemistry and food manufacturing has taken us far away from simple and much closer to complex. Instead of nacho cheese, we eat synthesized substances meant to approximate the flavor or texture of cheese, no milk products involved. Preservation, emulsification, hydrogenation, distillation, and esterification has resulted in some good things (like reduced spoilage and food borne diseases), but has also resulted in some questionable food additives like the compounds below.
I Can’t Believe It’s Not—Diacetyl!
Diacetyl is the chemical that gives microwave popcorn that delicious buttery flavor without the use of any butter. Unfortunately, extensive exposure to diacetyl can lead to a serious, irreversible, and rare condition known as bronchiolitis obliterans. First seen in workers at a microwave popcorn packaging plant, the condition is commonly known as “popcorn lung.” One consumer (who, somewhat freakishly, ate around four bags of microwaved popcorn a day) has developed the disease, and researchers recently discovered that small amounts of diacetyl can cause lung and airway damage in mice.
  • The Alternative? OSHA didn’t do crap to protect workers, but lawsuits and negative publicity scared some manufacturers into removing the compound from their packaged kernels. However, diacetyl abounds in packaged foods with fake butter flavor, often under the guise of “natural and artificial flavoring.” As for popcorn, pop your own and use the real golden stuff. Butter=good; popcorn lung=bad.
Would You Like Diet or Regular Benzene?
Benzene is an industrial solvent and a known carcinogen, so food companies generally try to keep it out of their products. However, two chemicals found in soda, sodium benzoate (a preservative) and ascorbic acid (vitamin C), can react to form benzene, especially in the presence of heat or light. In 2007, Coca-Cola and Pepsi agreed to settle lawsuits brought against them after benzene was detected in their products. The suit alleged that Pepsi’s Diet Wild Cherry drink had benzene levels nearly four times the maximum level set by the Environmental Protection Agency for drinking water. Oopsy. Both companies agreed to reformulate; however, thousands of soft drinks containing benzoate and citric acids are still on the market.
  • The Alternative? Probably most Coke and Pepsi products are “safe” (who knows what’ll turn up next!), but it’s a good idea to check the label.
Gone Fishin’—For Silly Puddy
The sticky texture of Silly Puddy is due, in part, to a widely used silicone-based polymer called polydimethylsiloxane (PDMS). In addition to Silly Puddy, it is also found in caulks, adhesives, cosmetics, silicone grease, knuckle replacements, silicone breast implants, and … in McDonald’s Fish Filet Patties. They add it as an “antifoaming agent.” I had to look this one up (why is the fish foaming?) and as it turns out, foam, produced when vats of liquids are mixed or agitated, is a big problem for large scale food manufacturers. Lots of foam means frying vats can’t be filled to capacity, meaning fast food restaurants can’t fry as many fish (potatoes, apple crisps, whatever) as mechanically possible. Hence the need for silicone oils like PDMS.
  • The Alternative? The FDA allows up to ten parts per million of anti-foaming agents to be used in food products; they’re found in many processed foods. Though not harmful at these levels, their use does increase the amount of acrylamide (a naturally occurring but nasty chemical) that is formed during frying.

Articulo completo aqui

No comments:

The "Silver Song"

Este video es obra creativa de Armando Isaac, para el curso de Química Inorgánica I.