Gums induced microstructure stability in Ca(II)-alginate beads containing lactase analyzed by SAXS

Abstract

Previous works show that the addition of trehalose and gums in β-galactosidase (lactase) Ca(II)-alginate encapsulation systems improved its intrinsic stability against freezing and dehydration processes in the pristine state. However, there is no available information on the evolution in microstructure due to the constraints imposed by the operational conditions. The aim of this research is to study the time course of microstructural changes of Ca(II)-alginate matrices driven by the presence of trehalose, arabic and guar gums as excipients and to discuss how these changes influence the diffusional transport (assessed by LF-NMR) and the enzymatic activity of the encapsulated lactase. The structural modifications at different scales were assessed by SAXS. The incorporation of gums as second excipients induces a significant stabilization in the microstructure not only at the rod scale, but also in the characteristic size and density of alginate dimers (basic units of construction of rods) and the degree of interconnection of rods at a larger scale, improving the performance in terms of lactase activity.

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

“…Pectin is part of the beads structure forming the 3D hydrogel network with alginate. The microstructure of the alginate hydrogel network determined by small‐angle X‐ray scattering (SAXS) showed that both compactness and density of alginate rods are drastically affected by other biopolymers (Traffano‐Schiffo et al ., , ), affecting the 3D network as well as water distribution. It was reported that pectin also forms rod‐like objects like alginate, of smaller size but with much higher flexibility, showing the ability to form different networks architecture (Schuster et al ., ), which may protect lycopene by improving interactions between them.…”

“…Many studies of encapsulation of bioactive compounds such as flavours, drugs, enzymes, vitamins, essential oils and carotenoids in a matrix or core system have been developed to control their release and protect them from deteriorative processes like oxidation, evaporation, degradation or thermal denaturation (Ray et al ., ; Traffano‐Schiffo et al ., , ). In particular, the simple and mild aqueous‐based gel formation achieved by the ionotropic gelling of Ca(II)‐alginate remains a very attractive alternative for biomedical, food and pharmaceutical applications.…”

“…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 ., ).…”

High-intensity ultrasound-assisted extraction of phenolic compounds from cowpea pods and its encapsulation in hydrogels

“…In this context, the encapsulation of phenolic compounds in biopolymer matrices represents a great possibility in their incorporation and consumption in different food systems [ 13 ]. The effectiveness of Ca(II)-alginate hydrogels in the stabilization and controlled release of biomolecules has been widely demonstrated [ 14 , 15 , 16 ].…”

Thermodynamic model of Ca(II)-alginate beads drying by spectrophotometry

“…For AS preparation, a 1% (w/v) alginate with 20% (w/v) sucrose was dropped into the 2.5% (w/v) CaCl 2 solution supplemented with 20% (w/v) sucrose using the same procedure previously described. A peristaltic pump (Damova S.L., Barcelona, Spain, model CPM-045B) was used to Ca(II)-alginate bead production according to the drop method described by Traffano-Schiffo et al, (2017), with a pump speed at 20 ± 0 rpm, regulated by an inverter Panasonic DV-700 (Oasaka, Japan) [12] . The CaCl 2 solution (with or without sucrose) was maintained in a cold bath with constant stirring by using a vortex IKA ® MS3 basic (IKA, Staufen, Germany).…”