The impact of food transformations on final nutritional quality of food products is a major question that has been studied only partially. This paper propose an assessment of different preservation processes with the light of two overall nutritional scores, positive (SAIN) and negative (LIM), developed in 2008, in response to a European regulation made to improve nutritional information on processed food. With the example of two different products, apple and pork meat, the objective is to monitor the nutritional scores as a function of the preservation operation chosen, isolated or combined, traditional or innovative. The results show that nutritional scores are very different as a function of the mass transfers involved during the preservation operation. The results give insights in the ability of a technological choice to modify the nutritional quality of a food item and potentially orientate a food label. This work also shows the limitations of using global nutritional scores as a tool to evaluate a food process.