Verification of Animal Origin of Thickeners in Food Products Using Low-Field NMR Spectroscopy: Case Study of Gelatin

Abstract Health benefits, religion, animal welfare, environmental protection, and food scandals are among the reasons why many people choose a vegetarian or vegan diet. In this study, the usage of low-field NMR spectroscopy at 80 MHz to identify the present of animal-derived thickener gelatin in food, especially in dairy products, was explored. The fingerprint of aromatic and NH x signals between δ 6.0 and δ 9.0 ppm can be used for identification and quantitative analysis of gelatin in the investigated products. External calibration curve was linear between 5 mg/mL and 25 mg/mL ( R 2 = 0.985). The limit of detection (LOD) and limit of quantification (LOQ) were defined as 0.14mg/g and 0.42mg/g with respect to finished products, respectively. More than 50 samples of vegan and non-vegan products (yoghurt, cream, pudding, mousse, and candies) were successfully investigated. NMR results correspond with the labelling information for all samples. Gelatin was predominately detected in mousse (median 3.3 mg/g), yoghurt (median 2.2 mg/g), and pudding (1.0 mg/g) samples. Gelatin was also detected in non-dairy candy samples with contents between 17 mg/g and 96 mg/g, which is consistent with the information on the packaging. Low-field NMR can be a quicker and cheaper alternative to conventional techniques for verification of animal origin of thickeners in food products.