I am sitting here drinking a Fresca (which is a calorie-free citrus soda), and was checking out the label. It says it contains glycerol ester of wood rosin, brominated vegetable oil, acacia, and carob bean gum. What are these ingredients, and why are they in my soda?
OK so I googled “glycerol ester of wood rosin” and found this from the Canada Department of Health Web site, which kind of explains what it is:
Provision currently exists in the Food and Drug Regulationsfor the use of glycerol ester of wood rosin, up to a maximum level of use of 100 parts per million (ppm), in citrus-flavoured or spruce-flavoured beverages. Health Canada has received a submission to revise the permitted area of use for glycerol ester of wood rosin as a density adjusting agent from “citrus-flavoured or spruce-flavoured beverages” to “beverages containing citrus oils or spruce oils”. Evaluation of available data supports the safety and effectiveness of this extended use of glycerol ester of wood rosin.
The broader area of use for glycerol ester of wood rosin will benefit consumers through the availability of a wider range of flavoured beverages in the marketplace. This extended use will also benefit the beverage industry by facilitating the production of a wider variety of beverages containing citrus and spruce oils.
Therefore, it is the intention of Health Canada to recommend that the Food and Drug Regulationsbe amended to permit the use of glycerol ester of wood rosin as a density adjusting agent in “beverages containing citrus oils or spruce oils”.
As a means to improve the responsiveness of the regulatory system, an Interim Marketing Authorization (IMA) is being issued to permit the immediate use of glycerol ester of wood rosin as indicated above while the regulatory process is undertaken to formally amend the Regulations.
I also found this: (Maybe I am answering my own question here)
The product improves the stability of citrus-oil flavor concentrates and beverages and is used as a weighting/clouding agent in such beverages as sports drinks.
And this:
In additon to extracts from citrus fruit, many citrus-flavored beverages contain glycerol ester of wood rosin, a by-product of chemical pulping. This chemical compound helps to emulsify the citrus flavorings so that they blend with the beverage.
Spruce-flavored drinks?? :eek:
Man, you canadians will drink anything, won’t you?
Obviously Zyada, you never tasted spruce beer. Either as pop or as the traditinal alcoholic beverage.
[Homer Simpson]Hmmmmm… spruce beer ![/Homer Simpson]
Considering most soda is just a combination of water, sugar, and various chemicals, aren’t you glad yours has an organically derived product in it? 
Oh God…Fresca. Back when I was in Viet Nam the local px would run out of all sodas except for Fresca. God how I hated that stuff. We would pray for restocking.
Prior to moving to “the South,” I had only heard of Fresca. They sell it everywhere here. I agree with Reeder. It’s nasty stuff. IMHO, of course.