Salted-fish and fish sauces, as well as wine and oil, are a key research subject because of their significant place not only in the diet but also in the many economic and socio-cultural spheres of Roman society. For a long time, identification has been based on painted inscriptions (tituli picti) and their association with the specific form of the containers, but new multidisciplinary approaches have been developing over the last twenty years. Following this trend, this contribution aims to show, from a methodological point of view, the potential and limits of archaeozoological and archaeobotanical analyses, applied to underwater contexts, in the study of paleo-contents concerning both fish and plant remains. In addition, this article presents new data from two archaeological sites (Arles-Rhône 3 and Bou Ferrer) that enable us to reveal the recurrent presence of these two types of remains together, which could indicate some salted-fish products mentioned in ancient literary sources, in particular related to garum or perhaps lymphatum