The influence of temperature on the heat transfer coefficient during moderate vacuum deep-fat frying of potato cylinders and "churros" was studied by Mir-Bel et al. (2012). The vacuum frying conditions used were oil temperatures of 100-140oC and moderate vacuum of 19.5-25.9 kPa. The h changes considerably, reaching a maximum of between 700- 1600 W.m.K for an oil temperature of 140°C and a thermal gradient of 40°C. To quantify the effect of oil temperature, pressure and size of the product on h, a parameter called"bubbling efficiency" (BE), was defined. BE related the bubble departure radius to the area/volume ratio of the product. An equation (the derivative of the Gompertz function) was proposed to estimate the mean h for each frying condition as a function of BE. The relation of h and BE showed a maximum corresponding to an optimal bubbling pattern.