Juice: If a person was stranded without safe drinking water or food, he could rehydrate and gain a few calories by drinking berry juice. To make it, place your confirmed edible berries in a clean bandana. They can be blackberries, raspberries, blueberries, or a blend of multiple species. Gather up the corners of the bandana and twist it so that the berries are enclosed. Mash the bundle a little with your hands, and twist the bandana even more to squeeze the juice into a waiting cup. Repeat the mashing and twisting until the juice stops running. This delicious drink provides vitamins, minerals, electrolytes, and, of course, much needed fluid. Consuming the juice in this way makes more sense than just eating the berries, as your your system would require stored water in your body to pass all those seeds.