Members of the New World primate genera Callithrix and Cebuella have specialisations for eating plant exudates. Exudates are also an important component of the diets of many other callitrichid species in the wild, especially at times of nutritional stress. Gum arabic is fed daily to all marmosets and to some tamarins in Jersey Zoo's collection. This study investigated species differences in liking for gum and the effects of the concentration of gum solutions on palatability. As predicted from field data, Callithrix species consumed more gum than other species; Saguinus also showed quite a strong liking for gum. In parallel with data from the wild, lion tamarins (Leontopithecus spp.) consumed the least, and Callimico also took relatively little. The two marmoset species tended to like stronger solutions of gum more than weak solutions and, therefore, the provision of smaller amounts of stronger concentrations is likely to be the most cost-effective way of incorporating gum into the diet. Providing gum to callitrichids on a regular basis can have significant welfare benefits.