ARTICLE | doi:10.20944/preprints202208.0232.v2
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: food safety; risk assessment; Cannabis sativa; tetrahydrocannabinol; food supplements; cannabidiol; benchmark dose; reference dose; liver toxicity
Online: 5 September 2022 (04:34:49 CEST)
At present, foods containing cannabidiol (CBD) and other cannabinoids are internationally being widely advertised and sold in increasing quantities. In the European Union (EU), these products require pre-marketing authorisation under the novel food regulation, so that all available CBD oils and CBD-containing food supplements in the EU are currently placed on the market with an infringement of the food laws. Currently, 19 CBD applications are under assessment at the European Food Safety Authority (EFSA). During the initial assessment of the application files, EFSA located several knowledge gaps that need to be addressed before the safety evaluation of CBD can be concluded. Namely, the effect of CBD on the liver, gastrointestinal tract, endocrine system, nervous system, psychological function, and reproductive system needs to be clarified. Nevertheless, the available literature allows a benchmark dose (BMD)-response modelling of several bioassays, resulting in a BMD lower confidence limit (BMDL) of 20 mg/kg bw/day for liver toxicity in rats. Human data in healthy volunteers found increases in the liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in a study at 4.3 mg/kg bw/day, which was defined by EFSA as a lowest observed adverse effect level (LOAEL). The EFSA panel currently concluded that the safety of CBD as a novel food cannot be evaluated, leading to a so-called clock stop of the applications until the applicants provide the required data. Meanwhile, the authors suggest that CBD products still available on the EU market despite the lack of authorisation must be considered as “unsafe”. Products exceeding a reference dose of 10 mg/day must be considered as being “unfit for consumption” (Article 14(1) and (2) (b) of Regulation No 178/2002), while the ones in exceedance of the human LOAEL must be considered “injurious to health” (Article 14(1) and (2) (a) of Regulation No 178/2002).
BRIEF REPORT | doi:10.20944/preprints202102.0116.v1
Subject: Chemistry, Analytical Chemistry Keywords: Bread; NMR Spectroscopy; Propionic Acid; Quality Control; Sorbic Acid
Online: 3 February 2021 (10:56:55 CET)
The food additive sorbic acid is considered as an effective preservative for certain cereal products, and propionic acid is commonly added in bakery wares, e.g. bread and fine bakery wares. The aim of this study is to develop and validate a new nuclear magnetic resonance spectroscopy (¹H NMR) method for routine screening and quantification of sorbic and propionic acids in bread and several bakery products for quality control purposes. Results showed that none of the screened samples contained higher concentrations than regulatory maximum limits. However, for some samples, labelling of preservatives was lacking or they were used in food categories, for which the use is not approved. It can be concluded that the developed NMR method can be used for routine screening of bakery products.
ARTICLE | doi:10.20944/preprints202008.0713.v1
Subject: Chemistry, Food Chemistry Keywords: NMR; alcoholic beverages; ethanol; methanol; acetaldehyde; screening; validation; food control; PULCON
Online: 31 August 2020 (06:21:35 CEST)
Due to legal regulations, the rise of globalised (online) commerce and the need for public health protection, the analysis of spirits (alcoholic beverages > 15 % vol) is a task with growing importance for governmental and commercial laboratories. In this article a newly developed method using nuclear magnetic resonance (NMR) spectroscopy for the simultaneous determination of 15 substances relevant for the quality and authenticity assessment of spirits is described. The new method starts with a simple and rapid sample preparation and does not need an internal standard. For each sample a group of 1H-NMR spectra is recorded, among them a 2D spectrum for analyte identification and 1D spectra with suppression of solvent signals for quantification. Using the Pulse Length Based Concentration Determination (PULCON) method, concentrations are calculated from curve fits of the characteristic signals for each analyte. The optimisation of the spectra, their evaluation and the transfer of the results are done fully automatically. Glucose, fructose, sucrose, acetic acid, citric acid, formic acid, ethyl acetate, ethyl lactate, acetaldehyde, ethanol, methanol, n-propanol, isobutanol, isopentanol, 2-phenylethanol and 5-(hydroxymethyl)furfural (HMF) can be quantified with an overall accuracy better than 8 %. This new NMR-based targeted quantification method enables the simultaneous and efficient quantification of relevant spirits ingredients in their typical concentration ranges in one process with good accuracy. It has proven to be a reliable method for all kinds of spirits in routine food control.
ARTICLE | doi:10.20944/preprints201911.0390.v1
Subject: Chemistry, Food Chemistry Keywords: caffeine; 16-O-methylcafestol; kahweol; furfuryl alcohol; tetramethylsilan (TMS); magnetic resonance spectroscopy; validation studies
Online: 30 November 2019 (10:20:17 CET)
Monitoring coffee quality as a means of detecting and preventing economically motivated fraud is an important aspect of international commerce today. Therefore, there is a compelling need for rapid high throughput validated analytical techniques such as quantitative proton NMR spectroscopy for screening and authenticity testing. For this reason, we sought to validate an NMR spectroscopic method for routine screening of coffee for quality and authenticity. A factorial experimental design was used to investigate the influence of NMR device, extraction time and nature of coffee on the content of caffeine, 16-O-methylcafestol (OMC), kahweol, furfuryl alcohol and 5-hydroxymethylfurfural (HMF) in coffee. The method was successfully validated for specificity, selectivity, sensitivity and linearity of detector response. The proposed method produced satisfactory precision for all analytes in roasted coffee, except for kahweol in canephora (robusta) coffee. The proposed validated method may be used for routine screening of roasted coffee for quality and authenticity control, as its applicability was demonstrated during the recent OPSON VIII Europol-Interpol operation on coffee fraud control.
COMMUNICATION | doi:10.20944/preprints202112.0420.v3
Subject: Chemistry, Analytical Chemistry Keywords: Non-targeted methods; method validation; food fraud; food authenticity; mass spectrometry; spectroscopy; NGS; NMR
Online: 23 May 2022 (11:10:00 CEST)
Through its suggestive name, non-targeted methods (NTMs) do not aim at a predefined "needle in the haystack". Instead, they exploit all the constituents of the haystack. This new form of analytical methods is increasingly finding applications in food and feed testing. However, the concepts, terms, and considerations related to this burgeoning field of analytical testing needs to be propagated for the benefit of ones associated in academic research, commercial development, and official control. This paper addresses the frequently asked questions around notations and terminologies surrounding NTMs. The widespread development and adoption of these methods also necessitates the need to develop approaches to NTM validation, i.e., evaluating the performance characteristics of a method to determine if it is fit-for-purpose. This work aims to provide a roadmap to approaching NTM validation. In doing so, the paper deliberates on the different considerations that influence the approach to validation and provides suggestions thereof.
ARTICLE | doi:10.20944/preprints202103.0446.v1
Subject: Chemistry, Analytical Chemistry Keywords: acrylamide; coffee; partial least square regression; NMR; LC-MS/MS
Online: 17 March 2021 (14:48:40 CET)
Acrylamide is probably carcinogenic to humans (International Agency for Research on Cancer, group 2A) with major occurrence in heated, mainly carbohydrate-rich foods. For roasted coffee, a European Union benchmark level of 400 µg/kg acrylamide is of importance. Regularly, the acrylamide contents are controlled using liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). This reference method is reliable and precise but laborious because of the necessary sample clean-up procedure and instrument requirements. This research investigates the possibility of predicting the acrylamide content from proton nuclear magnetic resonance (NMR) spectra that are already recorded for other purposes of coffee control. In the NMR spectrum acrylamide is not directly quantifiable, so that the aim was to establish a correlation between the reference value and the corresponding NMR spectrum by means of a partial least squares (PLS) regression. Therefore, 40 commercially available coffee samples with already available LC-MS/MS data and NMR spectra were used as calibration data. To test the accuracy and robustness of the model and its limitations, 50 coffee samples with extreme roasting degrees and blends were additionally prepared as test set. The PLS model shows an applicability for the varieties C. arabica and C. canephora, which were medium to very dark roasted using drum or infrared roasters. The root mean square error of prediction (RMSEP) is 79 µg/kg acrylamide (n=32). The PLS model is judged as suitable to predict the acrylamide values of commercially available coffee samples. On the other hand, very light roasts containing more than 1000 µg/kg acrylamide are currently not suitable for PLS prediction.