What Coke Contains
The Vons grocery store two miles from my home in Los Angeles, California sells 12 cans of Coca-Cola for $6.59 — 54 cents each. The tool chain that created this simple product is incomprehensibly complex.
Each can originated in a small town of 4,000 people on the Murray River in Western Australia called Pinjarra. Pinjarra is the site of the world’s largest bauxite mine. Bauxite is surface mined — basically scraped and dug from the top of the ground. The bauxite is crushed and washed with hot sodium hydroxide, which separates it into aluminum hydroxide and waste material called red mud. The aluminum hydroxide is cooled, then heated to over a thousand degrees celsius in a kiln, where it becomes aluminum oxide, or alumina. The alumina is dissolved in a molten substance called cryolite, a rare mineral first discovered in Greenland, and turned into pure aluminum using electricity in a process called electrolysis. The pure aluminum sinks to the bottom of the molten cryolite, is drained off and placed in a mold. It cools into the shape of a long cylindrical bar. The bar is transported west again, to the Port of Bunbury, and loaded onto a container ship bound for — in the case of Coke for sale in Los Angeles — Long Beach.
The bar is transported to Downey, California, where it is rolled flat in a rolling mill, and turned into aluminum sheets. The sheets are punched into circles and shaped into a cup by a mechanical process called drawing and ironing — this not only makes the can but also thins the aluminum. The transition from flat circle to something that resembles a can takes about a fifth of a second. The outside of the can is decorated using a base layer of urethane acrylate, then up to seven layers of colored acrylic paint and varnish that is cured using ultra violet light, and the inside of the can is painted too — with a complex chemical called a comestible polymeric coating that prevents any of the aluminum getting into the soda. So far, this vast tool chain has only produced an empty, open can with no lid. The next step is to fill it.
Coca-Cola is made from a syrup produced by the Coca-Cola Company of Atlanta. The main ingredient in the formula used in the United States is a sweetener called high-fructose corn syrup 55, so named because it is 55 per cent fructose or “fruit sugar” and 42 per cent glucose or “simple sugar” — the same ratio of fructose to glucose as natural honey. HFCS is made by grinding wet corn until it becomes cornstarch. The cornstarch is mixed with an enzyme secreted by a bacillus, a rod-shaped bacterium, and another enzyme secreted by a mold called Aspergillus. This process creates the glucose. A third enzyme, also derived from bacteria, is then used to turn some of the glucose into fructose.
The second ingredient, caramel coloring, gives the drink its distinctive dark brown color. There are four types of caramel coloring — Coca Cola uses type E150d, which is made by heating sugars with sulfite and ammonia to create bitter brown liquid. The syrup’s other principal ingredient is phosphoric acid, which adds acidity and is made by diluting burnt phosphorus (created by heating phosphate rock in an arc-furnace) and processing it to remove arsenic.
A much smaller proportion of the syrup is flavors. These include vanilla, which is the fruit of a Mexican orchid that has been dried and cured for around three months; cinnamon, the inner bark of a Sri Lankan tree; coca-leaf which comes from South America and is processed in a unique US government authorized factory in New Jersey to remove its addictive stimulant cocaine; and kola nut, a red nut found on a tree which grows in the African Rain Forest (this may be the origin of Coca-Cola’s distinctive red logo).
The final ingredient is caffeine, a stimulating alkaloid that can be derived from the kola nut, coffee beans and other sources.
All these ingredients are combined and boiled down to a concentrate, then transported from the Coca-Cola Company factory in Atlanta to Downey where the concentrate is diluted with water infused with carbon dioxide. Some of the carbon dioxide turns to gas in the water, and these gas bubbles give it effervescence, also known as “fizz,” after its sound. 12 ounces of this mixture is poured into the can.
The top of the can is then added. This is carefully engineered: it is made from aluminum, but it has to be thicker and stronger to withstand the pressure of the carbon dioxide gas, and so it uses an alloy with more magnesium than the rest of the can. The lid is punched and scored so that a tab opening, also made of aluminum, can be installed. The finished lid is put on top of the filled can, and the edges of the can are folded over it and welded shut. 12 of these cans are then packaged into a painted paperboard box called a fridge pack, using a machine capable of producing 300 such packs a minute.
The finished product is transported by road to a distribution center and then to my local Vons. This tool chain, which spans bauxite bulldozers, refrigerators, urethane, bacteria and cocaine, produces 70 million cans of Coca-Cola each day, one of which can be purchased for about two quarters on most street corners, and each of which contains far more than something to drink. Like every other tool, a can of Coke is a product of our world entire and contains inventions that trace all the way back to the origins of our species.
The number of individuals who know how to make a can of Coke is zero. The number of individual nations that could produce a can of Coke is zero. This famously American product is not American at all. Invention and creation is something we are all in together. Modern tool chains are so long and complex that they bind us into one people and one planet. They are not only chains of tools, they are also chains of minds: local and foreign, ancient and modern, living and dead — the result of disparate invention and intelligence distributed over time and space. Coca-Cola did not teach the world to sing, no matter what its commercials suggest, yet every can of Coke contains humanity’s choir.
After “What Coke Contains” was published, many people mentioned similar — and better — work that I did not know about and is well worth reading:
• ”I, Pencil,” a classic essay by Leonard E. Read (thank you, Chuck Grimmett of the Foundation For Economic Education, Bryce Miller and Michael Joseph.) Tom Snyder maintains a great web site about this essay.
• “When Ideas Have Sex,” a TED talk by Matt Ridley
• The excellent, “The Toaster Project,” by Thomas Thwaites, which I read long after I wrote this piece, and had not considered in this context until Nick Douglas, Editor of Slacktory, pointed out the similarity. Thank you, Nick.
And, yes, there really is a Murray River in Western Australia.