Archive for March 2013

Barbara Kingsolver Comes to Sweet Briar

Admittedly, Sweet Briar College doesn’t often sell out events or fill its auditorium. I’m pretty sure there are more seats than there are students. When someone as inspirational and respected as Barbara Kingsolver comes to speak, there’s suddenly a wait list. I can’t believe I’d never heard of her before a month or two ago and only then because it was an event I was required to go to for an English class. Kingsolver is a novelist who does research and writes about science-y things in a way that people not only find accessible but also that they can’t get enough of. On Thursday evening, she read from her latest novel, Flight Behavior, and spoke a bit about communication between the sciences and the arts. On Friday morning, Kingsolver was at a two-hour question and answer session, which I’m happy to say was very well attended by students majoring in sciences.

As a well-known author who went to college for science herself, her perspective and interest in bridging the gap between science and writing has added weight. For Flight Behavior, she traveled to Mexico to see the monarch butterflies in person, as well as to research labs to become intimately familiar with the lab atmosphere. For obvious reasons, her interest in having one foot in science and one foot in arts and communication made me super happy, but not as happy as seeing the popularity and enthusiasm of the crowd.

I was immensely impressed by both discussions I attended and yes, I bought the book. Below is the video streamed during her talk and reading in the Sweet Briar College Murchison Lane Auditorium on Thursday evening. Feel free to skip around the footage, but I highly recommend listening to the “talk” portion before the reading.

 

 

-Ashley

 

Why Are There Acronyms in My Food?

Even though there aren’t currently Twinkie’s or HoHo’s on the shelves, there are a plethora of other packaged foods that contain unpronounceable ingredients. There’s a lot of debate over whether or not it’s safe to consume these chemicals. Personally, I’d argue that we probably shouldn’t be eating things we can’t pronounce. For now, I’m interested in the chemistry behind why they were added by the food industry in the first place. I can’t cover all of them, but I did some research on a few major players in the world of food acronyms and additives.

File:LD-Swiss-Cake-Rolls.jpg

Still fresh, even after the apocalypse.

Apparently, metals such as copper and iron are a big problem for the food-producing industry. Trace amounts of metal, often from the water used in production, can have serious consequences on shelf-life. Metals can act as catalysts, which mean they speed up reactions. Transitions metals tend to increase the rates of reactions because they can easily give and take electrons from other molecules, which makes those other molecules more excited to react with each other (because all atoms need the correct number of electrons to be happy). As a result, if you have metal your in food, even in teensy, tiny amounts, the food will decompose faster. This problem is most apparent with things that have lots of water in them, like salad dressings and sauces.

A chemical called EDTA (Ethylenediaminetetraacetic acid) can be added to reduce the effects of metals on shelf-life. The structure of the molecule actually allows it to completely surround a metal atom (chelating), preventing the metal from reacting with the food. It’s like giving someone a big hug: they can’t take out their anger on anyone because they’re stuck but they feel better because their emotional needs are being met (like a molecule with the correct number of electrons is a happy molecule). EDTA is particularly useful for creating lower fat products because these products require a higher percent of water. The more water involved, the greater likelihood that there is metallic contamination (1).

There are other uses of EDTA that make it particularly interesting. For example, it can be used to treat heavy metal poisoning (2). In addition, (for the real chemistry nerds out there) it’s been used in labs to effectively sequester metal ions from solutions.

Some food additives are antioxidants. I’ve mentioned before that antioxidants are good for your body. They essentially slow down the aging process of your cells. Well, the same principle applies to antioxidants in food. The food will age more slowly if it doesn’t oxidize. It’s sort of like putting lemon juice on an apple to keep it from turning brown, except with chemicals that may or may not be safe to consume….

Butylated hydroxyanisole (BHA) and Butylated hydroxytoluene (BHT) are similar chemicals used as preservatives/antioxidants, especially in high-fat foods like potato chips that are likely to go rancid (bleh). BHA has been used in all sorts of contexts, ranging from cosmetics to rubber:

BHA is added to butter, lard, meats, cereals, baked goods, sweets, beer, vegetable oils, potato chips, snack foods, nuts and nut products, dehydrated potatoes, and flavoring agents. It is used in sausage, poultry and meat products, dry mixes for bever- ages and desserts, glazed fruits, chewing gum, active dry yeast, de- foaming agents for beet sugar and yeast, and emulsion stabilizers for shortening (IARC 1986). BHA stabilizes the petroleum wax coatings of food packaging (HSDB 2009) (3).

BHT is used in many of the same products. They are added to fatty foods because they are fat soluble, meaning they dissolve in fat (like how sugar is water soluble, meaning it dissolves in water), because they are stable at high temperatures (i.e. in boiling oil), and because oxygen prefers to react with the hydrocarbons rather than oils. Oxygen is the enemy of packaged food. The more oxygen reacts with additives, the longer the product’s shelf-life. BHA and BHT are diversions.

 

Tert-butylhydroquinone (TBHQ) is another common antioxidant, often used in conjunction with BHA and/or BHT. The idea behind the use of multiple antioxidants is that they work synergistically, meaning that they are more effective when used together than any of them would be individually (4).

Not all acronym additives are preservatives. MSG (monosodium glutamate) is a well-known food additive with potential side effects that have made many consumers skeptical. MSG was first isolated in 1866, but didn’t become popular as a food additive until 1908, when a Japanese chemist (Kikunae Ikeda) realized that glutamic acid, a component of MSG, had been flavoring soups for centuries. The production of MSG is now a trillion dollar international industry. It became popular because of the potency of its flavor, which is now associated with the term umami (meaning “deliciousness”) because the taste can’t quite be categorized as sweet, sour, salty, pungent, or bitter. It only takes 0.3 grams of MSG to flavor a liter of water (to break the “taste threshold”), whereas 2 grams of salt or 5 grams of sugar per liter are needed before they are detected. Chemical processes occur when MSG is added to some foods, like mushrooms and meats, that cause flavors in those foods that aren’t normally noticeable to become apparent:

MSG also has a strong synergistic effect with disodium inosinate and disodium guanylate, which are found in meat, fish, vegetables, and mushrooms. These substances are almost tasteless in the absence of MSG, but addition of even a small quantity of MSG to food that contains these nucleotides pro- duces an umami that is as much as six or eight fold greater than that to be expected from the quantity of MSG added (5).

Many food additives are meant to increase the stability of a product, while others are strictly to make it taste better. There’s a lot of controversy over whether or not these additives are related to diseases, particularly cancer. MSG is often associated with migraines and “Chinese Restaurant Syndrome.” It’s hard to say what effects these chemicals have on our bodies, but they are effective for the food industry.

 

Thanks for reading,

 

-Ashley

 

 

Sources:

(1) http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_003c/0901b8038003c0f7.pdf?filepath=versene/pdfs/noreg/113-01322.pdf&fromPage=GetDoc

(2) http://www.umm.edu/altmed/articles/ethylenediaminetetraacetic-acid-000302.htm

(3) http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/ButylatedHydroxyanisole.pdf

(4) http://www.inchem.org/documents/jecfa/jecmono/v042je26.htm

(5) http://www.cornellcollege.edu/chemistry/cstrong/512/msg.pdf