Thermal evaporation: representation of rise in boiling point of grapefruit juice.

摘要

The rise in boiling point of grapefruit juice was experimentally measured at soluble solids concn. in the range 9.3-60.6 degrees Brix and pressures between 6.0 x 103 and 9.0 x 104 Pa. Different approaches to represent experimental data, including the Duehring's rule, the Antoine equation and empirical models proposed in the literature were tested. In the range of 9.3-29.0 degrees Brix, the rise in b.p. was nearly independent of pressure, varying only with juice concn. Considerable deviations in this behaviour began to occur at concn. >29.0 degrees Brix. Experimental data could be best predicted by adjusting an empirical model, which consisted of a single equation that took into account the dependence of rise in b.p. on pressure and concn.