Microwave induced plasma optical emission spectrometry for multielement determination in instant soups

• Published in: Journal of food composition and analysis Vol. 86; p. 103376
• Main Authors: São Bernardo Carvalho, Larissa, Santos Silva, Caroline, Araújo Nóbrega, Joaquim, Santos Boa Morte, Elane, Muniz Batista Santos, Daniele Cristina, Andrade Korn, Maria Graças
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.03.2020
• Subjects: Food analysis; Food composition; Instant soups; Low level and trace elements determination; Microwave induced plasma; Microwave-assisted acid digestion; Microwave induced plasma; Food composition; Food analysis; Low level and trace elements determination; Instant soups; Microwave-assisted acid digestion
• ISSN: 0889-1575; 1096-0481
• DOI: 10.1016/j.jfca.2019.103376

•The application of MIP OES method for analysis of instant soups was demonstrated.•The method showed good accuracy and precision based on the analysis of three CRM.•Copper, K, Mg, Mn, P and Zn were determined in several instant soups samples.•Fast and simple method applicable for routine analysis was evaluated. This paper presents the use of microwave induced plasma optical emission spectrometry (MIP OES) for food analysis. A method for determination of Cu, K, Mg, Mn, P, and Zn in instant soups by MIP OES with N2 plasma was developed. Sample preparation procedure consisted of microwave-assisted digestion with dilute nitric acid solution. Accuracy was evaluated based on the analysis of three certified reference materials: NIST 1515 (apple leaves), NIST 1568b (rice flour) and NIST 3234 (soy flour). Recoveries ranged from 83.3–107.5 % for target elements in these materials. Addition and recovery experiments were performed and recoveries ranged from 86.0–106.0 %. All determinations were performed using external calibration. Limits of detection for Cu, K, Mg, Mn, P, and Zn were 0.09, 4.9, 1.0, 0.04, 5.4 and 0.88 mg kg-1, respectively. Concentrations ranges of Cu, K, Mg, Mn, P and Zn in various types of instant soups samples were found between 1.31–13.8, 1135 - 17.824, 172–567, 1.72–12.1, 608 - 1826 and 2.90–12.1 mg kg-1, respectively. The use of N2 microwave-induced plasma is demonstrated as a low cost alternative for routine analysis.