Finally, after almost two months my freeze dryer arrived. I bought it on a used equipment auction site. I couldn't resist putting something
in it as soon as it arrived - here are some pictures. This batch isn't for storage - it's just to see how various foods react to being freeze-dried in this particular machine. I'm going to have to play around with it until I come up with optimal processing times for each type of food.
My plan is to freeze-dry stuff in bulk and then seal in #10 cans from the LDS cannery (w/ O2
"Specimen" (food) chamber on top. This is cooled to about 0 degrees. Condensation chamber on bottom. This is cooled to -45 degrees. Water sublimates from food and condenses in the lower chamber as ice. The ice is removed periodically by a defrost cycle.
Pre-cooked fajita seasoned chicken strips, pre-cooked boneless chicken breasts and pre-cooked burger patties. All of these are just grocery store items from the freezer section.
Food loaded. Chicken, burgers, broccoli, green beans, corn and ice cream sandwiches (of course). I don't have the rack assembly installed yet. I'll have five racks after I do that.
After freeze-drying overnight.
Ice cream sandwich blowout. These weren't frozen solid enough before I turned on the vacuum. The lesson is one I should have remembered: You need
air in the freeze dryer to properly freeze the food. Without air there can be no convection, which is the most efficient way to move heat away from the food. The food has to be totally, completely rock-hard frozen before
turning on the vacuum.
I pulled an ice cream sandwich out and they are nearly done. They taste just like the Mountain House version and are crunchy and dry. The other food isn't nearly done. I expect it to take at least a week.
I'll update after this batch is done.