Application of undervalued natural resources in the formulation of nutritional and nutraceutical ingredients for healthy food formulations

FRANCO EMANUEL VASILE; MARÍA ALICIA JUDIS; MARÍA FLORENCIA MAZZOBRE

Campinas, Sao Paulo

Workshop; Reverse Engineering of Processed Food; 2017

FAPESP ? The São Paulo Research Foundation

The development of healthy foods has focused its attention on the replacement of synthetic additives for natural ones, which have a more positive image for a growing market increasingly aware onto effects of nutrition on health and wellness. In this context, the research of currently wasted natural resources, with technological food purposes, arises as an interestingalternative to obtain ingredients or additives with useful functional properties, able to be applied in the developed of innovativefood products. This is the case of the exuded gum obtained from Prosopis alba, a tree widely spread in the rural areas, at northeast region of Argentina. Under environmental stress conditions, Prosopis alba trees excrete a soluble and viscous hydrocolloid. In previous reports, we explored the physicochemical, nutritional, toxicological and functional properties of purified Prosopisalba exudate gum (G), finding that it shows several similarities with commercially available gums. This results have promoted the research of G applications in new technologies as microencapsulation of nutraceutical compounds. Based on this, the objective of this work was to evaluate the behavior of G as encapsulating agent in the stabilization of essential fatty acids and antioxidant compounds for the formulation of nutraceutical ingredients. Two approaches for bioactive protection were employed. One was the stabilization of essential fatty acids from fish oil in polyelectrolyte beads systems containing G as wall material component. For this, fish oil emulsions were prepared by dispersion of oil fraction (10% w/w) into aqueous solutions ofalginate (1% w/w) or alginate (1% w/w) and G (2% w/w). The resultant emulsions were introduced by dripping in a CaCl solution (2% w/v), and generated beads were then transferred to a chitosan solution (1% in HCl 0.1M) to promote the electrostatic adsorption of a chitosan layer. Beads were vacuum dried and storage in N2 atmosphere until analysis. By other side, antioxidantcompounds extracted from Jamaica (Hibiscus sabdariffa) calyxes in aqueous media (100°C, 10 min) were spray dried in presence of G and maltodextrin (MD) as carriers, in a final rate of 2:1 Jamaica dry solids: carrier blend (15% G, 85% MD). Additionally, an aqueous extract without excipients was spray dried and used as control. Microparticles obtained from spray drying process were stored in hermetic and opaque bags until analysis. In both cases, functional properties of G exerted a positive effect on structure, protection and stability of encapsulated bioactive compounds. Particularly, good emulsifying properties of G, resulted in stabilized fish oil emulsions, providing capsules with high load capacity (77%) and higher encapsulation yield (89%) regard tothe control (70% and 71% respectively). Gum-alginate interactions, improved the oil retention in the inner beads structure, delaying the oxidative damage during storage. This results could also be explained considering the antioxidants naturally present in G. In presence of G, microparticles obtained by spray drying of Jamaica aqueous extract show the highest encapsulation yield (80%) and similar final anthocyanin content (17 mg/100 g Jamaica solids) regard to control sample. G decreased the powder hygroscopicity and improved the physical structure of resulting in spherical shaped microparticles with good flow properties, while control sample shown a collapsed structure with bridges formation. Present results are promising and allowed considering P. alba gum as a novel non-conventional polyelectrolyte in the design of microstructure for theencapsulation of bioactive compounds for nutritional nutraceutical ingredient formulation with the added benefits to taking advantage of an available resource currently untapped.