Related Experiment Video
Updated: Dec 20, 2025

Fluorescent Paper Strips for the Detection of Diesel Adulteration with Smartphone Read-out
Published on: November 9, 2018
Qualitative and quantitative analysis based on digital images to determine the adulteration of ketchup samples with
Cynthia Giselle Reile1, María Susana Rodríguez1, David Douglas de Sousa Fernandes2
1Universidad Nacional del Sur, Departamento de Química, INQUISUR (UNS-CONICET), Av. Alem 1253 (B8000CPB), Bahía Blanca, Buenos Aires, Argentina.
Abstract:
Sudan I is a synthetic-azo dye commonly used to adulterate foods to increase sensory appearance. However, it is banned due to its carcinogenic, mutagenic and genotoxic properties, which represent a serious risk to human health. Thus, this paper proposes a feasibility study to identify and quantify Sudan I dye in ketchup samples using colour histograms (obtained from digital images) and multivariate analysis. The successive projections algorithm coupled with linear discriminant analysis (SPA-LDA) classified correctly all samples, while the partial least squares coupled with SPA for interval selection (iSPA-PLS) quantified adequately the adulterant, attaining values of RMSEP of 11.64 mg kg-1, R2 of 0.96, RPD of 5.28, REP of 13.63% and LOD of 39.45 mg kg-1. Therefore, the proposed methodology provides a simple, fast, inexpensive, promising analytical tool for the screening of both the quality and safety of ketchup samples. As a consequence, it can help to protect the consumer's health.
More Related Videos
12:50Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water
Published on: June 9, 2014
09:10Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce
Published on: October 18, 2010
Related Concept Videos
Qualitative Analysis
There are two main approaches to qualitative analysis:...
Karyotyping
Differential Staining Technique
Fixation and Sectioning
The simplest type of preparation is the wet mount, in which the specimen is placed in a drop of liquid on the slide. A liquid specimen can be directly deposited on the slide using a dropper. Solid specimens, such as skin scraping, can be placed on the slide before adding a drop of liquid to prepare the wet mount. Sometimes the liquid is simply water, but stains are often added...
Quantitative Analysis
In quantitative analysis, two key measurements are made: the sample quantity and a property proportional to the amount of the analyte (the substance being analyzed). This forms the basis of the...