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Pulp wood (but not the kind that may appear in your cheese or bread). Image courtesy of Flickr user rbglasson.

Ardent label readers out there know to scan nutritional labels for ingredients that they don’t want in their diet. But most people probably don’t keep an eye out for “wood pulp.” Well, chances are you won’t see that in print. Phrases you are more likely to encounter are innocuous-sounding terms such as “cellulose,” “cellulose gel,” or “dietary fiber.” The Wall Street Journal came out recently with a story on cellulose as a food additive, and some bloggers have been contributing their concerns about what’s being dumped into our food.

So, what exactly is cellulose? On the molecular level, it’s a string of sugar molecules. It’s the stuff that makes up the cell walls of plant matter. Cotton is an excellent source of cellulose in its purest form. Cellulose is a major component of wood, giving that material its signature strength. In the food industry, cellulose is used as a filler. Since humans don’t have enzymes that allow us to digest the stuff, it just passes through our digestive system, making it a go-to additive for diet products because it provides bulk without the caloric content. Cellulose is also used to make ice cream and cheeses smoother in consistency, and to keep strands of shredded cheese from sticking together. There are no known health risks and the FDA has limits on how much cellulose can be used in food products. It’s a natural additive, but the cellulose source might just gross out consumers.

The use of cellulose in food products is nothing new. Experiments in finding nutritionally neutral food sources date back to the early 20th century and the experiments of Frederick Hoelzel. An adventurous eater, he found that chopped surgical cotton doused with fruit juice could satisfy his appetite for a few days and in 1919, he developed cellulose-based flour. These early ventures didn’t fly with the American public. It wasn’t until 1955 that chemist Dr. O.A. Battista accidentally discovered edible cellulose by leaving a solution of cellulose and water in the blender a little too long. Expecting a gritty, sandy substance to end up at the bottom of the blender, he got a “noncaloric custard.” He used the flavorless gel to make a batch of cookies and, under the name Avicel, the product was quickly marketed to the food industry.

With the rising costs of raw materials like flour, oil and sugar, cellulose is going to be more attractive to manufacturers as a way to extend foodstuffs. For some people, this is cause to pinpoint the products that use the stuff. Personally, while I too prefer food that has been adulterated as little as possible, I think I might be more concerned about melatonin in my prefab brownies.