Protein concentrate is a recombinant glycoprotein/cellulose bio-matter used as a meat analogue that is quick to cook and with a protein content near identical to that of meat. Sold most commonly as flash-dried bricks similar to extra-firm tofu and with a somewhat rubbery feel, it has become a staple in most lower end cuisine.
Protein concentrate is usually comprised of a seventy-five (75%) to twenty-five (25%) percent ratio of glycoprotein/cellulose bulk material that undergoes a three stage process: liquefaction, recombination and extrusion. The G/C bulk powder material is first suspended in water before being heated to 150-200°C where thermoplastic proteins denature into a fibrous, insoluble and porous structure that can soak up as much as three times its weight in liquids. This solid mass of protein then undergoes recombination where a white, semi-translucent and gelatinous substance comprised of various essential vitamins, minerals, and amino acids is added to it. At this stage, the solid mass created can now be called protein concentrate. After the addition of flavor concentrates, the protein complex is then extruded into various shapes (chunks, flakes, nuggets, grains, and strips) and sizes before being packaged and sent out to various vendors.
Most people find protein concentrate to taste exactly the same as "real" meat (chicken, beef, pork, etc) although some claim to be able to tell the difference. Furthermore, protein concentrate is produced with acceptable nutritional value standards in mind.