Plastic recycling is a problem consumers can't solve

Re:Plastic recycling is a problem consumers can't solve by ars on Wednesday June 27, 2018 @08:15PM (#17413040)

And yet it did when I had food cooled by dry ice. So what counts more, what actually happened, or the theory?

The reason is that if the item is cold (especially right above freezing) you don't need much pressure to get CO2 to dissolve.

The food was weird it was all tingly and fizzy on the tongue. Kind of like the flavor of flat seltzer.

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Re:Plastic recycling is a problem consumers can't solve by mrob on Wednesday June 27, 2018 @09:52PM (#17413478)

Solubility of CO2 in water at 0C and roughly atmospheric pressure is about 0.001337 mole fraction [0]. CO2 molecules are 44/18 times heavier than water molecules, so that's about 3.3g of CO2 dissolved in a liter of water. Carbonated water is usually specified in "volumes of CO2". One mole of gas at STP has a volume of about 22.4L, so one liter of CO2 weighs about 2g. "Lightly carbonated" is usually considered about two volumes of dissolved CO2, so 4g/L, which isn't much higher than 3.3g. Assuming the packaging is sealed well enough to maintain a high percentage of CO2 within, and the temperature is low enough, it looks plausible that there would be a noticeable change in taste/mouth-feel. This is confirmed by a study I found showing average taste threshold for dissolved CO2 in water of 0.26g/L [1].

[0] http://sites.chem.colostate.edu/diverdi/all_courses/CRC%20re... [1] https://home.zhaw.ch/yere/pdf/Teil16%20-%20Expression%20of%2...

The theory supports ars. Calculate before you downvote.

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