Quantification of lactose and lactulose in hydrolysed-lactose UHT milk using capillary zone electrophoresis

Autor(es)

de Oliveira Neves, Leandra N. ^[1] ; Leal de Oliveira, Marcone A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Juiz de Fora, Dept Chem, BR-36036330 Juiz De Fora, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL DAIRY JOURNAL; v. 106, JUL 2020.
• Citações Web of Science: 3

Resumo

A new method for quantification of lactose and lactulose in hydrolysed-lactose UHT milk, using capillary zone electrophoresis with indirect detection in the ultraviolet region (CZE-UV), is proposed. A 3(3) Box-Behnken design for instrumental electrophoretic parameters optimisation was used, with the best conditions shown to be an injection pressure of 15 mbar 2 s, applied voltage of -20 kV, and cartridge temperature of 20 degrees C. Extraction procedures were investigated and protein precipitation using trichloroacetic acid solution was shown to give the best results. Limits of quantification for lactose and lactulose were 0.024 g 100 mL(-1) and 0.0094 g 100 mL(-1), respectively. Recovery levels ranging from 86% to 102% were obtained. The method was successful applied to several hydrolysed-lactose and regular UHT milk samples from six commercial leading brands. Results showed that all hydrolysed-lactose samples are in accordance with the legal recommendations to be classified as ``lactose-free{''} products. (C) 2020 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 14/50867-3 - INCT 2014: Instituto Nacional de Ciência e Tecnologia de Bioanalítica
• Beneficiário: Marco Aurelio Zezzi Arruda
• Modalidade de apoio: Auxílio à Pesquisa - Temático