Innovation and improvement in food fortification: Microencapsulation of vitamin B2 and B3 by a spray-drying method and evaluation of the simulated release profiles

Abstract

Food fortification helps to maintain, improve or correct nutrients requirements. The current paper explored the possibility of using the spray-drying method to produce microparticles with vitamin content suitable for incorporation in fortified food products. Vitamin B2 and vitamin B3 were microencapsulated with six different biopolymers (chitosan, modified chitosan, gum arabic, maltodextrin, sodium alginate and pectin), aiming with this research to highlight the similarities and differences. For these two categories of microparticles product yield, encapsulation efficiency, size and external morphology were determined. Afterward, in vitro release studies were performed under two different in vitro simulated conditions to evaluate: the time required for the vitamin to be released, the best kinetic models (Zero order, Higuchi, Korsmeyer–Peppas and Weibull) to describe the experimental release profiles and the main release mechanisms involved. Stability of the microparticles over 4 months of storage was also evaluated. The overall results lead to a successful microencapsulation process as for both vitamins the encapsulation efficiency reached values higher than 99% and the product yield ranged from 45% to 55% in the case of vitamin B2 and to 58% for vitamin B3. Through SEM characterization microparticles with regular or irregular spherical shape and with the smooth or rough surface were distinguished. The mean size of the microparticles loaded with vitamin B2 ranged in the interval 0.10 − 0.16 µm and the ones with vitamin B3 between 0.11 and 0.84 µm, considering a number distribution. With faster (minutes) or slower (hours) release, both types of microparticles showed a very good fitting especially to Weibull kinetic model and proved good stability over time since a vitamin loss lower than 10% was registered.

Graphical Abstract

Keywords:

• Biopolymers
• controlled release
• food fortification
• kinetic models
• microencapsulation
• spray-drying
• vitamin B2
• vitamin B3

Acknowledgments

This work was financially supported by: Base Funding - UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology and Energy – LEPABE – funded by national funds through the FCT/MCTES (PIDDAC); Project POCI-01-0145-FEDER-028715 (MicroDelivery – Development of controlled delivery functional systems by microencapsulation of natural and active compounds with therapeutic, nutritional and technological interest), funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; Berta Estevinho acknowledges FCT for the contract based on the “Lei do Emprego Científico” (DL 57/2016). The authors thank Fundação para a Ciência e a Tecnologia (FCT) for the doctoral grant PD/BD/105986/2014 of Ioana C. Carlan.