Wood Pulp Is Used As A Food Additive

Next Time You See 'Dietary Fiber' on a Food Label, You'll Know What It Is

Powdered cellulose: minuscule pieces of wood pulp or other plant fibers that coat the product and keep it from clumping by blocking out moisture. One of an array of factory-made additives, cellulose is increasingly used by the processed-food industry, producers say. Food-product makers use it to thicken or stabilize foods, replace fat and boost fiber content, and cut the need for ingredients like oil or flour, which are getting more expensive.

Cellulose products, gums and fibers allow food manufactures to offer white bread with high dietary fiber content, low-fat ice cream that still feels creamy on the tongue, and allow cooks to sprinkle cheese over their dinner without taking time to shred.

Powdered cellulose is made by cooking raw plant fiber—usually wood—in various chemicals to separate the cellulose, and then purified. Modified versions go through extra processing, such as exposing them to acid to further break down the fiber. Nutritionists say cellulose—which gives plants their structure—is a harmless fiber that can often cut calories in food. Insoluble dietary fibers like cellulose aren't digestible by humans so add bulk to food without making it more fattening.

Cellulose can serve as a good source of dietary fiber for people who don't eat enough fruits, vegetables or whole grains, Ms. Slavin says. The USDA's most recent dietary guidelines recommend young women get 28 grams a day of fiber and young men consume 38 grams.

The Food and Drug Administration sets limits on the amount of cellulose in certain foods like cheese spreads and jams. The USDA also limits the amount of cellulose in meat products to about 1% to 4%, depending on the type, in order to meet the agency's standards for protein content. (WSJ, 5/4/2011)