if you place fresh bud (or any fresh fruit) in a cooler with dry ice, it will freeze much colder than if it were in an extremely cold freezer. In fact, dry ice is NEGATIVE 109 degrees farenheit. The method of "dry ice canning" or "dry ice fruit preservation" is generally used to Individually Quick Freeze (IQF) berries and other small fruits / veggies, but if you were in a walk-in freezer, dry sifting a bunch of fresh dry-ice IQF'd buds, maybe you could have some fun? What about trimming directly into a cooler with dry ice? Maybe you could make some dry sift the same day that you trimmed? Or you could throw your IQF'd trim into some bubble bags after it had only been freezing for an hour or so! Dry ice freezing your buds would get them much colder than throwing dry ice into the water of a bubble bag mix. Three more weeks till I get to try any of this... Oh yeah don't close the cooler or it could explode.