Browsing by Author "Maria Paz Romero"

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    Comparative study of UPLC–MS/MS and HPLC–MS/MS to determine procyanidins and alkaloids in cocoa samples
    (Elsevier, 2010) Nadia Ortega; Maria Paz Romero; Alba Macia; Jordi Reguant; Neus Angles; Jose-Ramon Morello; Maria Jose Motilva
    This study develops a method using ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) to identify and quantify procyanidins, monomers to oligomers, and alkaloids, theobromine and caffeine, in cocoa samples. UPLC analyses were carried out using an Acquity HSS T3 column (100 mm 2.1 mmi.d., 1.8 mmparticle size) and gradient elution with water/acetic acid (99.8/0.2, v/v) and acetonitrile. This method was compared with an HPLC–MS/MS method in terms of speed, sensitivity, selectivity, peak efficiency, linearity, reproducibility, detection limits (LODs) and quantification limits (LOQs). Both methodologies were applied and compared to identify and quantify procyanidins and alkaloids from samples of cocoa nib. The results obtained showed that the UPLC–MS/ MSmethodology allow to determine procyanidins up to nonamers at low-concentration levels in a short analysis time, i.e. less than 12.5 min.
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    Obtention and characterization of Phenolic Extracts from different cocoa sources
    (2008) Nadia Ortega; Alba Macia; Neus Angles; Jose-Ramon Morello; Maria Jose Motilva; Maria Paz Romero; Jordi Reguant
    The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocaiteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources.
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    Obtention and Characterization of Phenolic Extracts from Different Cocoa Sources
    (2008-09) Nadia Ortega; Maria Paz Romero; Alba Macia; Jordi Reguant; Neus Angles; Jose-Ramon Morello; Maria Jose Motilva