title: Multi-elemental analysis of ready-to-eat "baby leaf" vegetables using microwave digestion and high-resolution continuum source atomic absorption spectrometry.
abstract: The mineral content (phosphorous (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu)) of eight ready-to-eat baby leaf vegetables was determined. The samples were subjected to microwave-assisted digestion and the minerals were quantified by High-Resolution Continuum Source Atomic Absorption Spectrometry (HR-CS-AAS) with flame and electrothermal atomisation. The methods were optimised and validated producing low LOQs, good repeatability and linearity, and recoveries, ranging from 91% to 110% for the minerals analysed. Phosphorous was determined by a standard colorimetric method. The accuracy of the method was checked by analysing a certified reference material; results were in agreement with the quantified value. The samples had a high content of potassium and calcium, but the principal mineral was iron. The mineral content was stable during storage and baby leaf vegetables could represent a good source of minerals in a balanced diet. A linear discriminant analysis was performed to compare the mineral profile obtained and showed, as expected, that the mineral content was similar between samples from the same family. The Linear Discriminant Analysis was able to discriminate different samples based on their mineral profile.
authors.affiliation: REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal.
authors.forename: J
authors.initials: J
authors.lastname: Santos
authors.affiliation: REQUIMTE, Departamento Engenharia Química, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal.
authors.forename: M T
authors.initials: MT
authors.lastname: Oliva-Teles
authors.affiliation: REQUIMTE, Departamento Engenharia Química, Instituto Superior de Engenharia do Porto, Instituto Politécnico do Porto, Porto, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Delerue-Matos
authors.affiliation: REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal. Electronic address: beatoliv@ff.up.pt.
authors.forename: M B P P
authors.initials: MB
authors.lastname: Oliveira
mesh_terms: D004063:Digestion; D008903:Minerals / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*; D013054:Spectrophotometry, Atomic / Q000379:methods*; D014675:Vegetables / Q000737:chemistry*
chemical_list: D008903:Minerals
keywords: Baby leaf vegetables; HR-CS-AAS; LDA; Microwave assisted digestion; Minerals