Untargeted metabolomics of fresh and heat treatment Tiger nut (Cyperus esculentus L.) milks reveals further insight into food quality and nutrition

• Published in: Journal of Chromatography A Vol. 1514; pp. 80 - 87
• Main Authors: Rubert, Josep, Monforte, Andoni, Hurkova, Kamila, Pérez-Martínez, Gaspar, Blesa, Jesús, Navarro, José L., Stranka, Milena, Soriano, José Miguel, Hajslova, Jana
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 08.09.2017
• Subjects: Amino Acids - analysis; Beverages; Chromatography, High Pressure Liquid; Cluster Analysis; Cyperus - chemistry; Cyperus - metabolism; Diglycerides - chemistry; Emulsifying Agents - chemistry; Fatty Acids - analysis; Fatty Acids - chemistry; Food authenticity; Food Quality; High-resolution mass spectrometry; Hot Temperature; Lipidomics; Metabolomics; Monoglycerides - chemistry; Plant Oils - analysis; Plant Oils - chemistry; Plant Oils - metabolism; Principal Component Analysis; Sugars - analysis; Sugars - chemistry; Tandem Mass Spectrometry; Tiger nut milk; Untargeted metabolomics; Vitamins - analysis; Lipidomics; High-resolution mass spectrometry; Tiger nut milk; Beverages; Food authenticity; Untargeted metabolomics
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2017.07.071

•The impact on the composition of fresh and UHT tiger nut milks was investigated.•UHT and fresh tiger nut milks were analyzed through a metabolomics approach.•Higher levels of biotin, phosphatidic acid and arginine were found in fresh drinks.•Untargeted metabolomics through HRMS allowed to find fine differences.•The results allowed to differentiate the nutrient loss caused by UHT treatment Tiger nut (Cyperus esculentus L.) is a crop traditionally grown in Valencia Region (Spain) and other temperate and tropical regions in the world, where its tubers are commonly consumed as tiger nut milk (horchata). Because of their nutritive potential and original taste, these products are beginning to spread internationally and, as consequence, analytical procedures to assess nutritional profiles, quality control issues are acquiring increasing relevance. The main objective of this study was to use an advance analytical method and chemometrics tools to determine if the ultra-high temperature (UHT) treatment necessary to extend the shelf life of tiger nut milk would affect the profile of nutrients when compared to fresh product. A cold solvent extraction followed by liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS) was used. Datasets obtained from UHT and fresh tiger nut milk data were analyzed through an untargeted metabolomics approach to compare chemical patterns, highlighting differences in citric acid esters of mono- diglycerides (CITREM) and monoacylglycerol (MAG) used as emulsifiers of UHT products, and a remarkably higher abundance of biotin, phosphatidic acid (PA) and L-arginine in fresh products. These results showed that untargeted metabolomics through high resolution tandem mass spectrometry allowed fine differences between food products to be found, therefore, the nutrient lost caused by UHT treatment was clearly discerned.