title: Encapsulating betalains from Opuntia ficus-indica fruits by ionic gelation: Pigment chemical stability during storage of beads.
abstract: Betalain encapsulation was performed by ionic gelation as a stabilization strategy for these natural pigments. Betalains were extracted from purple cactus fruits and encapsulated in calcium-alginate and in combination of calcium alginate and bovine serum albumin. Beads were characterised by scanning electron microscopy and thermal analysis using differential scanning calorimetry and thermogravimetry. Moisture sorption isotherms were determined. Bead morphology was affected by matrix composition. Pigments storage stability was evaluated at different equilibrium relative humidity and temperatures. Pigment composition of beads was determined by HPLC-MS-MS and degradation products were also analysed after storage; betalamic acid being the major one. Both types of matrices protected the encapsulated pigments, being their storage stability better at low relative humidity than that of the non-encapsulated control material. Antiradical activities of beads were proportional to remaining betalain contents. At high relative humidity, there was no protection and low storage stability was observed in the samples.
authors.affiliation: Centro de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago del Estero-CONICET, Santiago del Estero, Argentina.
authors.forename: María Carolina
authors.initials: MC
authors.lastname: Otálora
authors.affiliation: Departamento de Química, Universidad Nacional de Colombia, AA 14490 Bogotá, Colombia.
authors.forename: José Gregorio
authors.initials: JG
authors.lastname: Carriazo
authors.affiliation: Centro de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago del Estero-CONICET, Santiago del Estero, Argentina.
authors.forename: Laura
authors.initials: L
authors.lastname: Iturriaga
authors.affiliation: Departamento de Química, Universidad Nacional de Colombia, AA 14490 Bogotá, Colombia.
authors.forename: Coralia
authors.initials: C
authors.lastname: Osorio
authors.affiliation: Centro de Investigación y Transferencia de Santiago del Estero (CITSE), Universidad Nacional de Santiago del Estero-CONICET, Santiago del Estero, Argentina. Electronic address: manazar2004@yahoo.com.
authors.forename: Mónica Azucena
authors.initials: MA
authors.lastname: Nazareno
mesh_terms: D050858:Betalains; D002152:Calorimetry, Differential Scanning; D002851:Chromatography, High Pressure Liquid; D004339:Drug Compounding; D016166:Free Radical Scavengers; D005638:Fruit / Q000737:chemistry*; D005782:Gels; D008855:Microscopy, Electron, Scanning; D029747:Opuntia / Q000737:chemistry*; D010860:Pigments, Biological; D010936:Plant Extracts / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D013818:Thermogravimetry
chemical_list: D016166:Free Radical Scavengers; D005782:Gels; D010860:Pigments, Biological; D010936:Plant Extracts; D050858:Betalains
keywords: Antioxidants; Antiradical activity; Betacyanins; Betalamic acid (PubChem CID: 5281176); Betanin (PubChem SID: 10733); Cactus pear; Capsules; Encapsulation; Indicaxanthin (PubChem CID: 6096870); Isobetanin (PubChem CID: 6325438)