Lollipops are popular candies, usually consisting of hard candy mounted on a stick. The modern lollipop was invented by George Smith in USA in 1908 and named after a racehorse called Lolly Pop. The name lollipop was trademarked in 1931.

The Original Gourmet Food Company manufactures lollipops in a variety of flavours and colours.

The primary ingredient in these lollipops is sugar. Sugar is C₁₂H₂₂O₁₁ and has a molar mass of 342.2 g/mol. The lollipops have a diameter of about 33 cm and a density of about 1540 kg/m³.

The goal is to estimate their mass transfer rate. Initially assume that we can model sucking on them by considering their diffusion in still water at 37^oC; what would be the initial mass transfer rate?

The model is modified to consider their diffusion as a large suspended sphere in water at 37^oC. Estimate the increase in the mass transfer rate?

At 37^oC, the density of water is 994 kg/m³ and its viscosity is 6.947x10-4 Pa s. The estimated diffusivity of sugar in water near 37^oC is 0.5 x 10-9 m² /s (Ziegler et al., 1987). The solubility data indicates that 250 g of sugar can be dissolved in 100 g of water.

Ziegler, G.R. et al. (1987) Determination of mass diffusivity of simple sugars in water by the rotating disk method Journal of Food Science, https://doi.org/10.1111/j.1365- 2621.1987.tb06655.x