A meat grinder can be used to produce edible extract from pine needles. Here is one mounted on a wooden frame for stability. All of the parts for building the frame and attaching the grinder can be found at a local hardware store.
The needles are fed into the meat grinder, which is then cranked by hand. The pressure from the grinding process breaks the cell walls of the needles and pushes the protein and juices out of the grinder, leaving the indigestible fiber behind.
The pulp (shown here) that is left behind is indigestible by humans, but can be given to livestock for nutrition. The juice that is produced is then thickened and strained to produce a solid that can be eaten by humans.