Chemometric analysis of amino acid profiles for detection of fruit juice adulterations – Application to verify authenticity of blood orange juice

• Published in: Food chemistry 2021-05, Vol.343, p.128452, Article 128452
• Main Authors: Wistaff, Emma A., Beller, Silvia, Schmid, Anton, Neville, John J., Nietner, Thorben
• Format: Article
• Language: English
• Subjects: Adulteration; Amino acid profiles; Amino Acids - analysis; Authentication; Blood orange juice; Chemometrics; Citrus sinensis - chemistry; Food Contamination - analysis; Fruit and Vegetable Juices - analysis; Fruit juice; Informatics; Least-Squares Analysis; Multivariate analysis; Principal Component Analysis
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2020.128452

•Fruit juices were differentiated by chemometric evaluation of their amino acid profiles.•Profiles were considered in a blood orange juice versus blond orange juice adulteration study.•20 percent blond orange juice adulterant could be detected in blood orange juice.•Developed chemometric approaches are useful for analytical food fraud investigation. In this work, fruit juices have been analyzed by high-performance liquid chromatography (HPLC) to measure whole amino acid profiles for various fruit types. The fruit juice authentication capabilities of whole amino acid profiles employed in various multivariate analysis methods including principal component analysis (PCA) and partial least squares (PLS) analysis have been investigated. PCA of the profiles exhibited a good separation of most fruit types and were validated using quality control samples. Furthermore, these profiles were considered in a blood orange juice versus blond orange juice adulteration study. Applying PLS regression allowed for the detection of ~20 percent blond orange juice adulterant added in blood orange juice. The highest regression coefficients were found for glutamic acid and valine, with regards to blood orange juice, and for phenylalanine and glycine, with regards to orange juice. These results suggest that chemometric approaches have great potential for the implementation in food testing.