Characterisation of Curcumin-loaded Egg Albumin Powder

Abstract

Curcumin was encapsulated using egg albumin as a carrier material by desolvation and spray drying methods. Curcumin-loaded egg albumin powder was analysed for its in vitro release pattern, structural changes, morphology, stability, and antioxidant capacity. In vitro release studies showed that the cumulative release of 5.32, 47.76, 50.58, and 60.63% from pure curcumin from the powders prepared using ethanol, acetone, and spray drying, respectively, in 72 h. The FT-NIR spectrum of curcumin-loaded egg albumin powder confirmed that the curcumin and egg albumin maintained their chemical structure during drying process. FESEM images revealed that particles were in spherical shape and in the size ranges of 50 nm to 400 nm and 50 nm to 350 nm for nanoparticles prepared using ethanol and acetone, respectively. SEM images of spray dried particles showed that the particle size ranged from 1 μm to 15 μm without any agglomeration. Curcumin retentions of 74.66, 75.93, and 70.64% were observed in powder prepared using ethanol, acetone, and spray drying, respectively, after 50 min of heating at 100 ºC. Thus, the encapsulated samples were thermally stable, and could be used in food preparations as natural yellow colourant as functional food ingredient. Total antioxidant capacity of curcumin-loaded egg albumin powder prepared using ethanol, acetone, and spray drying was 5.96±0.89, 4.58±0.23, and 6.97±0.44 μg of ascorbic acid equivalents, respectively, at 100 μg.ml-1 sample concentration. Curcumin retained within the formulations was found to be stable without any change in the physical appearance throughout the storage period.