Introduction: The most commonly used methods to determine and identify Norwalk virus are based on molecular biology. Methods: A viral extraction protocol from food samples was studied in this work using artificial contamination test. It consists of a new protocol with a phase of viral elution from the food matrix performed using an eluting solution (glycine and beef extract at 3% pH 9) and a concentration phase with polyethylene glycol 8000. To detect Noroviruses, two techniques of molecular biology, polymerase chain reaction and real-time polymerase chain reaction, were compared. At the same time, tests of direct viral identification were conducted on soft fruits and salad obtained from the market. Results: From the results obtained it was possible to evaluate how the phase of viral recovery represents an important critical point of the protocol. Conclusion: It was possible to identify a greater sensitivity of the real-time polymerase chain reaction compared with the traditional polymerase chain reaction.