My experience is that Aloe doesn't have a long shelf, but I have been told to try a couple of things, the first being to take the branch off the plant
and wrap it up outer skin and all in foil and store it in the refrigerator, breaking off pieces as you need them. it worked well for a couple of weeks then got mushy, gross, and finally frozen. The second method was to take a branch off and slice it down the center and scrap the Aloe gel out into a airtight container a refrigerate that- so far this has worked,though the cold seems to thin out the gel somewhat. Maybe you can keep it cold in a cooler or with an ice pack, I am wondering if you can just take branch off and carry it with you with no refrigeration any cut you make on an Aloe will seal itself over- but I don't know. I can tell you that Aloe works wonders for skin problesm/ medicinal purposes, I have had a nasty seasonal rash on my hands every summer for years, I bought an Aloe plant
and the gel will stop the itch, burn, swelling in minutes. I hear it is great for sunburn as well.