Different corpuses are analysed by means of co-word analysis, in the framework of technological watch of the industrial valorization of plant proteins. The comparison of keyword clusters reveals unequal results, raising the question of the relevance of information retrieval. The corpuses compiled do not provide all the important signals that can be expected from this type of study. Research on several data bases (five) provides increasingly detailed images which allow for rapid progress, with the experts, towards critical points of information.