|MadSci Network: Other|
Interesting question but I am going to have to challenge your underlying assumption. The straws used in different fast food restaurants are not linked to the carbonation levels in the fountain carbonated soft drinks (soda, soda pop, pop, soft drink, coke, etc) they serve.
The description "fountain" is used to describe the fact that the beverage is "thrown" or mixed at the restaurant. The dispenser mixes a highly concentrated version of the soda ("pre-mix" of color, flavor, sweetener, acid, caffeine and preservatives) with carbonated water when the lever is pressed. These machines are supposed to be calibrated regularly but often, the soda from one machine can be very different from the same product out of another machine. Keep in mind also, it is possible that some fast food restaurants may intentionally set their machines for a lower pre-mix concentration to make it last longer.
As for the straws being different diameters, I think that is luck of the straw... I mean draw... The length and diameter of the straw is usually determined by each fast food restaurant's parent company through a purchasing contract with various suppliers. There isn't (and shouldn't be) any correlation between the straw diameter and the carbonation levels of their fountain drinks. If there were, it would create a nightmare for the soda manufacturers, who would then have to produce different pre- mixes for different customers. And the specifications would have to change if the restaurant changed straw suppliers...
Anyway, thanks for your question. And for your story about finding us. It's always fun to hear how people "find" us on the web.
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