Fingerprinting black tea: When spectroscopy meets machine learning a novel workflow for geographical origin identification.

Food fraud, along with many challenges to the integrity and sustainability, threatens the prosperity of businesses and society as a whole. Tea is the second most commonly consumed non-alcoholic beverage globally. Challenges to tea authenticity require the development of highly efficient and rapid solutions to improve supply chain transparency. This study has produced an innovative workflow for black tea geographical indications (GI) discrimination based on non-targeted spectroscopic fingerprinting techniques. A total of 360 samples originating from nine GI regions worldwide were analysed by Fourier Transform Infrared (FTIR) and Near Infrared spectroscopy. Machine learning algorithms (k-nearest neighbours and support vector machine models) applied to the test data greatly improved the GI identification achieving 100% accuracy using FTIR. This workflow will provide a low-cost and user-friendly solution for on-site and real-time determination of black tea geographical origin along supply chains.

Recent food safety and fraud issues within the dairy supply chain (2015-2019).

Milk and milk products play a vital role in diets around the globe. Due to their nutritional benefits there has been an increase in production and consumption over the past thirty years. For this growth to continue the safety and authenticity of dairy products needs to be maintained which is a huge area of concern. Throughout the process, from farm to processor, different sources of contamination (biological, chemical or physical) may occur either accidently or intentionally. Through online resources (the EU Rapid Alert System for Food and Feed (RASFF) and HorizonScan) safety and fraud data were collected from the past five years relating to milk and milk products. Cheese notifications were most frequently reported for both safety alerts (pathogenic micro-organisms) and fraud incidences (fraudulent documentation). Alongside the significant number of biological contaminations identified, chemical, physical and inadequate controls (in particular; foreign bodies, allergens, industrial contaminants and mycotoxins) were also found. Although the number of incidents were significantly smaller, these contaminants can still pose a significant risk to human health depending on their toxicity and exposure. Grey literature provided a summary of contamination and fraud issues from around the globe and shows its potential to be used alongside database resources for a holistic overview. In ensuring the integrity of milk during ever changing global factors (climate change, competition between food and feed and global pandemics) it is vital that safety and authenticity issues are continually monitored by industry, researchers and governing bodies.

Identification of vegetable oil botanical speciation in refined vegetable oil blends using an innovative combination of chromatographic and spectroscopic techniques.

European Regulation 1169/2011 requires producers of foods that contain refined vegetable oils to label the oil types. A novel rapid and staged methodology has been developed for the first time to identify common oil species in oil blends. The qualitative method consists of a combination of a Fourier Transform Infrared (FTIR) spectroscopy to profile the oils and fatty acid chromatographic analysis to confirm the composition of the oils when required. Calibration models and specific classification criteria were developed and all data were fused into a simple decision-making system. The single lab validation of the method demonstrated the very good performance (96% correct classification, 100% specificity, 4% false positive rate). Only a small fraction of the samples needed to be confirmed with the majority of oils identified rapidly using only the spectroscopic procedure. The results demonstrate the huge potential of the methodology for a wide range of oil authenticity work.

Rapid surface plasmon resonance immunobiosensor assay for microcystin toxins in blue-green algae food supplements.

A surface plasmon resonance (SPR) immunobiosensor assay was developed and validated to detect microcystin toxins in Spirulina and Aphanizomenon flos-aquae blue-green algae (BGA) food supplements. A competitive inhibition SPR-biosensor was developed using a monoclonal antibody to detect microcystin (MC) toxins. Powdered BGA samples were extracted with an aqueous methanolic solution, centrifuged and diluted in HBS-EP buffer prior to analysis. The assay was validated in accordance with the performance criteria outlined in EU legislation 2002/657/EC. The limit of detection (LOD) of the assay was calculated from the analysis of 20 known negative BGA samples to be 0.561 mg kg(-1). The detection capability (CCß) of the assay was determined to be ≤ 0.85 mg kg(-1) for MC-LR. The biosensor assay was successfully applied to detect MC-LR toxins in BGA samples purchased on the Irish retail market. MC-LR was detected in samples at levels ranging from <0.5 to 2.21 mg kg(-1). The biosensor results were in good agreement with an established LC-MS/MS assay. The assay is advantageous because it employs a simple clean-up procedure compared to chemical assays and allows automated unattended analysis of samples unlike ELISA.

Determination of pantothenic acid in foods by optical biosensor immunoassay.

An optical biosensor inhibition immunoassay was developed using a specific pantothenic acid-binding protein for the quantitation of free pantothenic acid (vitamin B5) in foodstuffs. Samples were prepared by a simple extraction procedure in buffer, and vitamin content was estimated against authentic calibrants in the same buffer. Performance parameters included a working range of 10-5000 ng/mL, a limit of detection of 4.4 ng/mL, precision relative standard deviation of 5.4-7.1% over a range of concentrations, and recoveries > 95% in the matrixes tested. A wide range of foodstuffs, including National Institute of Standards and Technology reference samples, were tested in 3 independent laboratories and the results were compared with microbiological assay and liquid chromatography/mass spectrometry (LC/MS) methods. The results indicate that the biosensor technique is appropriate for the estimation of pantothenic acid in a wide range of foodstuffs.