Encapsulation of a free-solvent extract of lycopene in alginate-Ca(II) beads containing sugars and biopolymers

Abstract

Background:The purpose of the present study was to enhance the stability toward isomerization and control the release of an encapsulated free-solvent extract of lycopene, obtained from a nonconventional natural source, by means of alginate beads containing sugar (trehalose) and biopolymers (chitosan, low methoxyl pectin, and arabic gum). Methods:Lycopene was extracted from freeze-dried pulp of pink grapefruit obtaining a free solvent extract. Lycopene encapsulation was conducted by a double procedure consisting of emulsification and ionotropic gelation in alginate-Ca(II) beads, modified by the addition of sugar and biopolymers. The influence of beads' composition was studied on lycopene stability and release, as well as molecular mobility and diffusion in the beads. Results and Conclusions:The addition of a second excipient (besides alginate) in the formulation should be carefully conducted, since stability during alginate-Ca(II) bead generation could be even compromised, leading to high lycopene losses. Beads containing trehalose and chitosan were the ones that best preserved the lycopene content and minimized isomerization changes. This could be related to the reduced molecular mobility and lower diffusion coefficient of this system. Lycopene release was severely affected by the composition of the beads, allowing to modulate its release depending on a desired application. Then, a good strategy to obtain high lycopene formulations ready to use or for their incorporation in a subsequent technological process (such as freeze-drying or extrusion) was reported in the present study.

Pink grapefruit lycopene encapsulated in alginate‐based beads: stability towards freezing and drying

“…Diffusion coefficient was determined by LF‐NMR and reported in Table S2 for FD beads. A great reduction on diffusion in one order of magnitude was observed after drying respect to wet beads (Aguirre Calvo & Santagapita, ; Aguirre Calvo et al ., ), from around 0.37–0.52 × 10 −9 to 0.05 × 10 −9 m 2 s −1 or less. Considering that the values for edible oils are around 9 × 10 −12 m 2 s −1 (Šmejkalová & Piccolo, ), the obtained values are higher, but is important to consider the different employed techniques and that LF‐NMR is near the detection limit for this analysis.…”

“…Lycopene was successfully encapsulated in Ca(II)‐alginate beads, obtaining loading efficiencies higher than 80% in presence of trehalose and chitosan (Aguirre Calvo & Santagapita, ). Beads sizes ranged between 2.7 and 2.2 (±0.1), similar to previous reported data (Aguirre Calvo & Santagapita, ), being those with chitosan and β‐CD the ones of lower size and higher circularity.…”

“…Beads were prepared by ionotropic gelation accordingly to the drop method described previously using the same reported parameters (Aguirre Calvo & Santagapita, ). A peristaltic pump model BT50‐1J header JY10 (Boading Longer Precision Pump Co, Ltd, China) was used to drop 10 mL of the emulsions to 100 mL of the external media, summarised in Table S1 of Supplementary File.…”

“…However, some disadvantages are associated with this carrier, including high biomolecule leakage, low mechanical strength, large pore size and low cryo‐ and dehydro‐capacities (Santagapita et al ., ; Traffano‐Schiffo et al ., ), revealing the need to add other matrix components. In a previous work, it was shown that alginate beads with the addition of sugars and biopolymers were capable of enhancing the stability towards isomerisation as well as control the release of an encapsulated free‐solvent extract of lycopene (Aguirre Calvo & Santagapita, ; Aguirre Calvo et al ., ) and enzymes (Traffano‐Schiffo et al ., , , ). Lycopene is a naturally occurring red carotenoid pigment present in tomatoes, watermelon, pink grapefruit, pink guava and papaya (Sinha & Dua, ) with health benefits associated with lower risk of some degenerative diseases that may play a specific role in preventing prostate cancer and cardiovascular disease (Costa‐Rodrigues et al ., ).…”

Opportunities and Challenges of Plant Bioactive Compounds for Food and Agricultural-Related Areas

“…Furthermore, all possible applications of bioactive compounds from different plant sources have not yet been fully reported. The use of fruits, fruit, or vegetable pulp for scientific research is very popular [38][39][40]. Recently, there has been spreading attention in transforming waste into value-added products.…”