The invention concerns the use, in a composition for treating textile fiber articles in aqueous or moist medium, of an amphoteric polysaccharide, whereof the native skeleton is a polysaccharide consisting of a main chain comprising anhydrohexose units and branches comprising at least a neutral or anionic anhydropentose and/or anhydrohexose unit, the anhydrohexose and/or anhydropentose units being substituted of modified by groups bearing at least a (potentially) anionic load and/or at least a (potentially) cationic load, the degree of substitution or modification by the set of said groups bearing (potentially) anionic loads ranging between 0.01 and less than 3, with a ratio of the number of (potentially) anionic charges over the number of (potentially) cationic loads ranging between 99.5/0.5 to 30/70, as agent for preventing degradation and/or enabling to protect the colors of said articles and/or providing said articles with crease-resistant and/or softening properties