Mung bean starch gels, of 4.5-14 wt % solid content, were stored at room temperature and at 4°C in a refrigerator and then cracked quasi-statically by driving a 40° included-angle wedge into intact specimens in order to determine their fracture toughness. The work to fracture of the gels, calculated without respect to energy loss due to viscoelasticity or to frictional effects between wedge and gel, varied from 0.5 to 22 J m−2 and were higher for those gels stored at low temperature. For gels stored at room temperature, the effect of viscoelasticity and wedge-gel friction was examined. Hysteresis (viscoelastic energy losses) was concentrationdependent. In 8 wt % gels, it accounted for about 10% of the total work done in the wedge tests and did not depend significantly on crosshead speed. Frictional work, largely due to adhesion between the gel and the wedge, was negligible at low speeds but increased rapidly with crosshead speed. However, whether correction factors are introduced or not, the results substantiate the very low fracture toughness of gels. Between 5 and 11 wt % concentrations, the work of fracture varied linearly with gel concentration. Variation in crosshead speed from 2 to 200 mm min−1 increased the work to fracture by a factor of two.