Lists of foods with the highest protein content exist online at Bodybuilding.com, WebMD.com and Wikipedia.org, as of April 2015. The Bodybuilding.com and Wikipedia lists organize the food by type, while WebMD offers a simple list.
The foods on Bodybuilding.com's list include Greek yogurt, steak, chicken, fish and beans. The portion sizes vary, and the list includes additional information about each food. There is also a frozen foods section.
Wikipedia's list standardizes the serving size to 100 grams, and it breaks down food groups into high- and low-protein tiers. For instance, the cheese category reports Parmesan, at 40 grams, as having the highest protein content, and ricotta, at 11 grams, as the having the lowest. The highest concentration of protein on the list is bearded seal meat.