In order to determine the quantity of protein in food, it is important to have standardized analytical methods. Several methods exist that are used in different food industries to quantify protein content, including the Kjeldahl, Lowry, Bradford and total amino acid content methods. The correct determination of the protein content of foods is important as, often, as is the case with milk, it determines the economic value of the food product and it can impact the economic feasibility of new industries for alternative protein production. This editorial provides an overview of different protein determination methods and describes their advantages and disadvantages