Pulp and ultrafiltered cactus pear extracts were encapsulated
with Capsul by spray-drying [52]. Betacyanin and
betaxanthin encapsulation efficiency reached values
above 98% for both systems, this efficiency being attributed
to strong interaction between betalains and the
polymer. The betacyanin degradation rate constant was
significantly higher for the encapsulated pulp than for the
encapsulated ultrafiltered extract, suggesting that the
mucilage or higher sugar content of the former increased
the hygroscopicity of the microparticles, leading to the
degradation of betalain. Hydrolysis (Figure 3) was the
main mechanism for betanin degradation during storage
of the microparticles.