beta-carotene encapsulation in a mannitol matrix as affected by divalent cations and phosphate anion.

The effects of addition of divalent cations and phosphate buffer on the degree of beta-carotene encapsulation in a mannitol matrix during freeze-drying were analyzed. The degradation rate of encapsulated beta-carotene as a function of % RH and its relationship with the physical state of the matrix during storage at 25 degrees C was also studied. The presence of phosphate salts significantly delayed mannitol crystallization at a highly satisfactory degree during freeze-drying and, consequently, the degree of beta-carotene encapsulation increased.