I had a Facetime conversation with an anonymous Slurpee scientist who shared the jargon used by researchers when describing certain aspects of Slurpee nature. Below are screen grabs from that chat along with the samples used to illustrate the terminology.
Cavitation describes the air pockets that form inside the Slurpee which are caused by an over-frozen product "laying the loops" incorrectly. "Ideally a Slurpee has no air pockets larger than a standard carbonation bubble, or SCB," says the Slurpee scientist. I'll add that this matches no definition of the word cavitation that I've ever encountered, and I consider it to be one of my favorite words ever. Right up there with blustery.
Liminal Rifting describes pockets of liquid collecting mid-Slurpee or "in the middle third" as the guy put it. I quote: "You know you have liminal rifting if the top of the liquid packet is angled or curved, a horizontal line towards is indicative of cross glaciation. Liminal rifting can be a real problem for both store and customer as the slush and clinkers are buoyed up by the downward pressure of the heavier liquid... This is why you sometimes have a Slurpee start squirting slush out the straw hole."
I once had this happen and I dripped Slurpee all over some high school kids. I bought them their drinks as an apology.
Cross Glaciation is marked by horizontal lines of carbonation above dark lines of liquid. "This is considered sub-optimal from a corporate stand-point because of [bad note taking here, something about the syrup ratio costing pennies more] but it often makes for a more delicious Slurpee. You can induce cross and sub-glaciation by filling a cup half full of slush and then adding a centiliter of regular soft drink of regular soft drink, then filling the remainder with Slurpee slush."
Knowledge is power.