Oxidation stability index (OSI) on storage
The OSI graphs of freeze dried and spray dried solid microcapsules
and co-microcapsules stored at 5 °C and 25 °C for 90
days are presented in Fig. 4. The OSI value for freeze dried
samples was significantly lower than that of spray dried
samples, implying that the freeze dried microcapsules and comicrocapsules
were less stable against oxidation when
compared to the spray dried ones. This relatively poor oxidative
stability in freeze dried microcapsules is attributed to the
highly porous structure of freeze dried sample that allow easier
diffusion of oxygen through to the encapsulated oil and also
increases the amount of surface oil