Hey fellas, thanks for caring so much about game meat care. Yeah, Caribou Gear has copied everything they possibly can to make a buck, even claims of "coming up with the idea of synthetic game bags technology"...what a joke.
I believe Aron and Bitterroot have nailed the best advice, and those articles of mine help also.
Some questions about spray bottles and citric acid app, as well as bone-in vs debone and meat immersion therapy have been raised. Here are a few more thoughts:
1. Backpack-style remote hunting requires a modification of Alaska techniques. In Alaska, remote hunts are the norm, requiring long periods of meat care in the field during transport. Aron is a strong supporter of de-boning, for good reason. Elk bones weigh about 18 lbs total, and that makes sense to remove if travelling with meat on your back up and over hillcountry. He's also diligent with hands on techniques to prevent issues with spoilage threats.
2. Meat immersion is best approached during the first 24 hours post harvest, since core temps range from 101 degrees and 103 degrees (extremophil and thermophil bacteria ideal temps). The goal within the first 24 hours is to quickly reduce deep-tissue temps as low as possible without freezing (34-50 degrees F). If your hunt is less than 5 days long from kill time to road access, submerge game within a trash bag under "moving current". Streams with flow cool meat 25X faster than air current. If lake water is used, pre-treat your meat with citric acid to help stave off giardia and other stagnant bacteria. Rivers have cooler temps than lake water, usually averaging 5 degree F lower. The faster the water the cooler and quicker your meat will reduce core temps. I prefer to immerse meat during daytime and hang at night to foster drying. Or, if travelling by daytime, immerse at night and move out during the day. Use your judgment in your own scenario, as long as you concentrate on lowering core temps to well below 50 degrees within the first 30 hours post harvest.
3. Citric acid use is great for the reasons we've covered. Remember that re-dosing is necessary every other day, and if immersed meat will condensate and wash away your acid at the surface, so daily treatment will also help. If you don't want to take a spray bottle afield, take citric acid powder and use a bandana to apply the acid mixture by making solution in your cooking pot or water bottle, then soak and apply water from the bandana...as long as it the acid gets applied, the delivery method is irrelevant. 1 oz powder to 1 qt water will suffice.
4. Bone-in theory on benefits: Leg bones attached provide leverage when handling heavy qtrs, and if rafting or packrafting...leg bones help keep meat balanced on the watercraft. Bone-in also adds weight that you'll have to deal with, but reduces the surface area to require trimming at home. Bone-in meat saves about 25% more meat by the end, sometimes as much as 40% depending on handling in the field and how dry you kept the meat. Again, your personal situation will dictate your technique.
5. Citric acid affects surface color: If you notice your game turning gray or weird shades of pasty-dark...this is a result of the effects of citric acid. trimming will remove unsightly color changes at the surface, perfectly normal affects of citric acid.
6. Bacteria threats come in two major stages: 1) Bone sour results from the inside out, starting at the bone or core. These bacteria are anaerobic (thrive without oxygen) and results from core heat greater than 85 degrees, especially within the first 36 hours. Meat appears fine at the surface, but when you cut into it, odor changes smell putrefied...bone sour and meat turns green and iridescent. Quick dismemberment off the carcass and meat immersion are the best actions; 2) surface bacterial invasion results from handling actions (or inactions). Poop, dirt, urine, bile, contaminated hair, and absorption odors from fuel, exhaust from wheelers, or other sources. These bacteria are aerobic (require oxygen, high pH, high temps, and moisture to thrive). These are the easiest forms to control by handling techniques. Remember clean, cool, and dry will help reduce the invasion. Citric acid lowers pH at the surface and retards bacterial growth. Clean dismemberment and handling reduces the initial doses of bacterial sources, which help you in the long run. Keeping meat dry retards bacterial environments and reduces invasion. Air circulation helps dry meat. hanging qtrs fosters blood vessel drainage (remember veins and arteries hold blood that will spoil and become bacterial spoilage, and they run up and down the legs, so hanging allows this fluid to drain. hanging for 24 hours is a good idea for gravitational assistance, but if I had to choose between hanging and immersion....sink it for cooling properties and hang as often as you can.
7. Meat separation and game bag sizes: the less dense your meat bags are the better for cooling deep tissue areas. Separate meat into many small bags if possible so that air reaches more surface and allows trapped heat to dissolve.
That's probably more info that any of you wanted, but hope it helps. Holler with more questions if I missed anything.
Larry