Safe food through better labelling: A robust method for the rapid determination of caprine and bovine milk allergens

Accidental milk cross-contamination is one of the most common causes for costly food recalls. Yet, quantifying trace-levels of allergen is time-consuming and current methods are not adapted for routine analyses making quality control for trace-level allergen content impractical. This perpetuates voluntary “may-contain” statements that are unhelpful for people suffering from food allergies. Here, we developed a rapid LC-MS method enabling milk allergen quantification by comparing all tryptic-peptides of major milk allergens. The bovine-specific αS-2 casein peptide and allergen-epitope NAVPITPTLNR provided excellent performance in sensitivity (LOD 1 mg.kg − 1; LOQ 2 mg.kg − 1) across various dairy products, good recovery rates in baked croissants (77 % with a 10 % inter-day RSD) and a linear range of 2 – 2,000 mg.kg − 1. The method can be used for routine determination of trace-contamination with bovine milk allergen and the adulteration of high-value caprine dairy products with lower-value bovine milk products, protecting consumer trust and the growing population suffering from food allergies

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Secure Food-Allergen Determination by Combining Smartphone-Based Raw Image Analyses and Liquid Chromatography–Mass Spectrometry for the Quantification of Proteins Contained in Lateral Flow Assays

The current food safety testing system, based on laboratory-based quantification, is difficult to scale up in line with the growth in the export market and does not enable traceability through the nodes of the food supply system. Screening assays, for example, lateral flow assays (LFAs), can improve traceability but often lack the required reliability to guarantee compliance. Here, we present an alternative pipeline for secure on-site compliance testing, using allergens as a case study. The pipeline features smartphone-driven LFA quantification and an liquid chromatography–mass spectrometry (LC–MS) method enabling direct quantification of the allergens contained in the LFA. The system enables swift and objective screening and provides a control measure to verify LFA assay reliability. For the smartphone assay, 8-bit RGB and grayscale colorimetric channels were compared with 16-bit raw intensity values. The latter outperformed RGB and grayscale channels in sensitivity, repeatability, and precision, while ratiometric ambient light correction resulted in excellent robustness for light-intensity variation. Calibration curves for peanut determination using two commercial LFAs featured excellent analytical parameters (R2 = 0.97–0.99; RSD 7–1%; LOD 3–7 ppm). Gluten determination with a third commercial LFA was equally established. A prediction error of 13 ± 11% was achieved for the best performing assay. Good performance–calibration curves (R2 = 0.93–0.99) and CVs (<15%)– were observed for the analyte quantification from the LFA by LC–MS. The LOD for the LC–MS assay was 0.5 ppm, well below the LODs reported for the LFAs. This method creates a digital, fast, and secure food safety compliance testing paradigm that can benefit the industry and consumer alike

The benefits of carbon black, gold and magnetic nanomaterials for point-of-harvest electrochemical quantification of domoic acid

Gold nanostars (GNST), gold nanospheres (GNP) and carbon black (CB) are chosen as alternative nanomaterials to modify carbon screen-printed electrodes (c-SPEs). The resulting three kinds of modified c-SPEs (GNP-SPE, CB-SPE and GNSP-SPE) were electrochemically and microscopically characterized and compared with standardized c-SPEs after pretreatment with phosphate buffer by pre-anodization (pre-SPE). The results show outstanding electrochemical performance of the carbon black-modified SPEs which show low transient current, low capacitance and good porosity. A competitive chronoamperometric immunoassay for the shellfish toxin domoic acid (DA) is described. The performances of the CB-SPE, GNP-SPE and pre-SPE were compared. Hapten-functionalized magnetic beads were used to avoid individual c-SPE functionalization with antibody while enhancing the signal by creating optimum surface proximity for electron transfer reactions. This comparison shows that the CB-SPE biosensor operated best at a potential near − 50 mV (vs. Ag/AgCl) and enables DA to be determined with a detection limit that is tenfold lower compared to pre-SPE (4 vs. 0.4 ng mL−1). These results show very good agreement with HPLC data when analysing contaminated scallops, and the LOD is 0.7 mg DA kg−1 of shellfish.This project has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 720325.Peer reviewe

ASSURED Point-of-Need Food Safety Screening: A Critical Assessment of Portable Food Analyzers

Standard methods for chemical food safety testing in official laboratories rely largely on liquid or gas chromatography coupled with mass spectrometry. Although these methods are considered the gold standard for quantitative confirmatory analysis, they require sampling, transferring the samples to a central laboratory to be tested by highly trained personnel, and the use of expensive equipment. Therefore, there is an increasing demand for portable and handheld devices to provide rapid, efficient, and on-site screening of food contaminants. Recent technological advancements in the field include smartphone-based, microfluidic chip-based, and paper-based devices integrated with electrochemical and optical biosensing platforms. Furthermore, the potential application of portable mass spectrometers in food testing might bring the confirmatory analysis from the laboratory to the field in the future. Although such systems open new promising possibilities for portable food testing, few of these devices are commercially available. To understand why barriers remain, portable food analyzers reported in the literature over the last ten years were reviewed. To this end, the analytical performance of these devices and the extent they match the World Health Organization benchmark for diagnostic tests, i.e., the Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, and Deliverable to end-users (ASSURED) criteria, was evaluated critically. A five-star scoring system was used to assess their potential to be implemented as food safety testing systems. The main findings highlight the need for concentrated efforts towards combining the best features of different technologies, to bridge technological gaps and meet commercialization requirements