Spray Drying Encapsulation of Elderberry Extract and Evaluating the Release and Stability of Phenolic Compounds in Encapsulated Powders

摘要

Elderberry (Sambucus nigra L.), rich in polyphenols, has recently attracted great interest in functional food, nutraceutical, and pharmaceutical industries, due to their potential health benefits to humans. However, polyphenols are very sensitive compounds and unstable. The utilisation of encapsulated polyphenols, instead of free compounds, can overcome some of their limitations. The extraction of the polyphenols from the elderberry flowers and stems was made, followed by the microencapsulation of the extract by a spray drying process. The microparticles were characterised by size, morphology, and release profile. The microencapsulated polyphenols were completely released, with total release times that range from 600 to 1140 s. The kinetic models that have a better adjustment to the practical results are the zero order, the Korsmeyer-Peppas, and the Weibull models, with correlation coefficients that range from 0.900 to 0.999. The encapsulation efficiency was similar for all the analysed particles, being the results located in a range from 92.3 to 99.8%. After 8 months of storage, the microparticles were revaluated, being possible to conclude that the elderberry microparticles present very similar release profiles comparing with the ones obtained with fresh microparticles, which proves the successful encapsulation of the elderberry extract and the stability of the microparticles over time. This experimental work leads to a very successful encapsulation of elderberry extract.