Impact of Raw Materials and Production Processes on Furan and Acrylamide Contents in Dark Chocolate

Characterisation of new sources of acrylamide in food marketed in Belgium

This study provides occurrence data for acrylamide in various foodstuffs, including those covered by Recommendation (EU) 2019/1888, from 210 samples purchased on the Belgian market. Detection frequencies exceeded 84% in potato-based products other than fries, vegetable crisps, black olives, cocoa powders, coffee substitutes and cereals and snacks. Large variations in acrylamide levels were found in cereals and snacks, with no correlation between cereal type or processing. Snacks containing chia did not show higher acrylamide levels than other cereal-based snacks. Maximum levels found were 4389 and 3063 µg kg-1 in coffee substitutes and vegetable crisps, respectively. Potato-based products contained 2 to 27 times less acrylamide when prepared in oven, compared to deep fryer processing. Artificially oxidised "Californian-style" black olives contained five times more acrylamide than "Greek-style" olives. In bread, pastries, nuts, oilseeds, dried fruits and confectionaries, detection frequencies varied from 27 to 69% and the average acrylamide content was <30 µg kg-1.

Food process contaminants: formation, occurrence, risk assessment and mitigation strategies - a review

Thermal treatment of food can lead to the formation of potentially harmful chemicals, known as process contaminants. These are adventitious contaminants that are formed in food during processing and preparation. Various food processing techniques, such as heating, drying, grilling, and fermentation, can generate hazardous chemicals such as acrylamide (AA), advanced glycation end products (AGEs), heterocyclic aromatic amines (HAAs), furan, polycyclic aromatic hydrocarbons (PAHs), N-nitroso compounds (NOCs), monochloropropane diols (MCPD) and their esters (MCPDE) which can be detrimental to human health. Despite efforts to prevent the formation of these compounds during processing, eliminating them is often challenging due to their unknown formation mechanisms. It is critical to identify the potential harm to human health in processed food and understand the mechanisms by which harmful compounds form during processing, as prolonged exposure to these toxic compounds can lead to health problems. Various mitigation strategies, such as the use of diverse pre- and post-processing treatments, product reformulation, additives, variable process conditions, and novel integrated processing techniques, have been proposed to control these food hazards. In this review, we summarize the formation and occurrence, the potential for harm to human health produced by process contaminants in food, and potential mitigation strategies to minimize their impact.

Analytical methods, risk assessment, and mitigation strategies for furan in processed foods in various countries

This article provides an overview of analytical methods for measuring furan levels in food. Given the potential carcinogenicity of furans in humans, several studies have focused on assessing furan levels in various food products. In this review, we specifically examine furan levels in foods that are central to regional culinary traditions and summarize the results of country-specific risk assessments. Consequently, we have identified foods that contribute significantly to dietary furan exposure in each region. Coffee and baby foods, regardless of region, emerged as the primary sources of furan intake among adults and infants, respectively. Several previous studies have been conducted to develop various mitigation strategies aimed at reducing exposure to furan through food intake. Therefore, in this paper, we categorize effective mitigation strategies into two main groups: alterations to processing conditions and the addition or removal of food additives and ingredients.

Polyether sulfone flat-sheet membrane impregnated with Mn-Al layered double hydroxide nanoparticles for green microfiltration of acrylamide in cocoa products

A new polyether sulfone (PES) membrane modified with manganese-aluminum layered double hydroxide (Mn-Al LDH) was prepared and utilized in the membrane micro-solid phase extraction (M-µSPE) of acrylamide for the first time. The analyses were conducted using HPLC-UV. The extraction efficiency of the PES membrane was enhanced two-fold with the addition of LDH. The fabricated LDH@PES was characterized using ATR-FTIR, SEM, XRD, and nitrogen adsorption/desorption isotherms. The specific surface area, average pore diameter, thickness, cross-sectional channels, and LDH particle size of the LDH@PES membrane were determined. The extraction key factors including membrane composition, desorption conditions, sample pH, and salt concentration were studied. The method was validated by determining the limit of detection, the limit of quantification, linear range, r2, matrix effect, enrichment factor, and precision. Extraction recoveries ranged from 87.4 to 103.5% with RSD < 5.9%. Finally, the method's green features were assessed with the AGREE protocol. This is the first report on the application of LDH@PES for microfiltration/extraction of acrylamide in various chocolate and cocoa products.

Enhancing analysis of neo-formed contaminants in two relevant food global commodities: Coffee and cocoa

Neo-formed contaminants (NFCs) are common in many foods, especially those subjected to high-temperature processing. Among these contaminants, products arising from the Maillard reaction, sugar reduction, thermal degradation of polyphenols and lipid oxidation, including acrylamide, furan, furfuryl alcohol, and hydroxymethylfurfural, are consistently linked to potential neoplastic effects. NFCs are found in globally traded commodities like coffee and cocoa, posing a significant risk due to their frequent consumption by consumers. A direct correlation exists between consumption frequency, exposure levels, and health risks. Hence, it's crucial to establish reliable methods to determine levels in both matrices, aiming to mitigate their formation and minimise risks to consumers. This review offers a comprehensive examination, discussion, and identification of emerging trends and opportunities to enhance existing methodologies for extracting and quantifying NFCs in coffee and cocoa. By presenting an in-depth analysis of performance parameters, we aim to guide the selection of optimal extraction techniques for quantifying individual NFCs. Based on the reviewed data, headspace extraction is recommended for furan, while solid and dispersive solid phase extractions are preferred for acrylamide when quantified using gas and liquid chromatography, respectively. However, it is worth noting that the reported linearity tests for certain methods did not confirm the absence of matrix effects unless developed through standard addition, leading to uncertainties in the reported values. There is a need for further research to verify method parameters, especially for determining NFCs like furfuryl alcohol. Additionally, optimising extraction and separation methods is essential to ensure complete compound depletion from samples. Ideally, developed methods should offer comprehensive NFC determination, reduce analysis time and solvent use, and adhere to validation parameters. This review discusses current methods for extracting and quantifying NFCs in coffee and cocoa, highlighting emerging trends and emphasising the need to improve existing techniques, especially for compounds like furfuryl alcohol.

Acrylamide increases and furanoic compounds decrease in plant-based meat alternatives during pan-frying

Plant-based meat alternatives are gaining popularity as protein sources. However, pan-frying may lead to the formation of potentially harmful food contaminants. We investigated the formation of acrylamide and furanoic compounds in four different plant-based meat alternatives and two meat burger patties during pan-frying at 160 and 200 °C. The highest acrylamide contents (72. ± 7.7 and 69.2 ± 9.5 µg/kg, respectively) were found in soy flour- and sunflower-protein based patties fried at 200 °C. Unprepared pea and soy protein-based burger patties contained the highest furfural amounts (2832.8 ± 576.2 and 2683.0 ± 868.5 µg/kg, respectively). Furfuryl alcohol content was highest in soy flour-based patties and increased temperature-dependently up to 1120.9 ± 383.4 µg/kg. Based on the tolerable intake calculated by the EFSA Scientific Panel on Contaminants in the Food Chain, these amounts do not pose a health risk. Nevertheless, since plant-based novel food are being increasingly consumed, further investigations into the formation of food contaminants in novel processed foods are warranted.

A comprehensive review of furan in foods: From dietary exposures and in vivo metabolism to mitigation measures

Furan is a thermal food processing contaminant that is ubiquitous in various food products such as coffee, canned and jarred foods, and cereals. A comprehensive summary of research progress on furan is presented in this review, including discussion of (i) formation pathways, (ii) occurrence and dietary exposures, (iii) analytical techniques, (iv) toxicities, (v) metabolism and metabolites, (vi) risk assessment, (vii) potential biomarkers, and (viii) mitigation measures. Dietary exposure to furan varies among different countries and age groups. Furan acts through various toxicological pathways mediated by its primary metabolite, cis-2-butene-1,4-dial (BDA). BDA can readily react with glutathione, amino acids, biogenic amines, or nucleotides to form corresponding metabolites, some of which have been proposed as potential biomarkers of exposure to furan. Present risk assessment of furan mainly employed the margin of exposure approach. Given the widespread occurrence of furan in foods and its harmful health effects, mitigating furan levels in foods or exploring potential dietary supplements to protect against furan toxicity is necessary for the benefit of food safety and public health.

Microwave Roasting as an Alternative to Convection Roasting: Sensory Analysis and Physical Characterization of Dark Chocolate

Roasting cocoa beans by means of microwave radiations seems to be a potential alternative to convection roasting, but little is known about the impact of this method on the perceived flavor profile of the chocolate. Therefore, this research focused on revealing the flavor perception of chocolate produced with microwave roasted cocoa beans assessed by both a trained panel and chocolate consumers. Samples of 70% dark chocolate produced from cocoa beans microwave roasted at 600 W for 35 min were compared with samples of 70% dark chocolate produced from cocoa beans convectively roasted at 130 °C for 30 min. Non-significant differences (p > 0.05) in the measured physical properties, such as color, hardness, melting, and flow behavior, showed that chocolate produced from microwave roasted cocoa beans can exhibit the same physical qualities as convection roasted chocolate. Moreover, combined discriminative triangle tests, with 27 judgements in total, performed by a trained panel, showed that each type of chocolate exhibited distinctive characteristics (d'-value = 1.62). Regarding the perceived flavor, "cocoa aroma" was cited as significantly higher for the chocolate produced from microwave roasted cocoa beans (n = 112) compared to chocolate produced from convection roasted cocoa beans (n = 100) by consumers. Both preference and willingness to buy were higher, though insignificant at a 5% level, for the microwave roasted chocolate. A final potential benefit (studied in this research) of microwave roasting cocoa beans is the reduced energy consumption, which was estimated at 75%. Taking all these results together, the microwave roasting of cocoa is shown to be a promising alternative to convection roasting.

Efficient optimization and development of two methods for the determination of acrylamide in deep-frying oil by liquid chromatography-tandem mass spectrometry: Application of multifactor analysis assessment strategy

A new multifactor analysis assessment strategy was developed for evaluating, optimizing, and comparing analytical techniques for acrylamide in frying oils. Based on five indices (absolute recovery, absolute matrix effect, the intensity of the full ion scan, and the precursor ion scan to m/z 184 and m/z 241), the proposed strategy was performed with radar analysis, relative contribution analysis, and the entropy-weighted technique for order performance by similarity to ideal solution analysis. Two novel methods based on quick, easy, cheap, effective, rugged, and safe extraction methodology and gel permeation chromatography-liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry have been developed for the analysis of acrylamide in frying oils. Two methods were suitable for rapid and sensitive analysis of acrylamide in oils in different laboratories, with a limit of quantitation at 2 μg/kg, and the average recovery ranging from 92.5% to 107.8%, with relative standard deviations below 10%. When considering automation efficiency and matrix effects, gel permeation chromatography is the most efficient method, whereas the other method has an advantage when analyzing large samples. The developed methods were used in a pilot study to analyze frying oils with acrylamide content below 9.82 μg/kg, showing that the repeated frying process did not produce significant content of acrylamide in oils.

Analysis of Furan in Red Pepper Powder Treated by Three Methods-Boiling, Roasting, and Frying

In this study, furan analysis was conducted on dried red pepper powder treated by three cooking methods (boiling, roasting, and frying). A total of 144 samples were prepared and their furan levels were analysed using automated solid-phase micro-extraction gas chromatography-mass spectrometry. The furan concentration in boiled soup ranged from 1.26 to 4.65 ng/g, and from 7.37 to 27.68 ng/g for boiled red pepper samples. For the roasting method, a furan concentration between 6.66 and 761.37 ng/g was detected. For the frying method, the furan level of edible oils ranged from 3.93 to 125.88 ng/g, and a concentration ranging from 4.88 to 234.52 ng/g was detected for the fried red pepper samples. The cooking method using edible oil obtained a higher furan concentration than the water-based method. Samples using corn germ oil (linoleic acid-rich oil) obtained the highest furan concentration among the four edible oils. In all cooking methods, the higher the heating temperature and time, the higher the furan concentration detected. A kinetic study was conducted using the roasting model system and the apparent activation energy was 60.5 kJ/mol. The results of this study could be useful as a database for furan concentration in dried red pepper powder according to various cooking methods.

Influence of Water, NaCl and Citric Acid Soaking Pre-Treatments on Acrylamide Content in French Fries Prepared in Domestic Conditions

The aim of this study was to investigate the influence of some pre-treatment applications toward acrylamide mitigation in potatoes fried in domestic conditions modeled after those found in Romania, by using a pan and a fryer. Before being fried in a pan, potato strips were treated in one of the following ways: soaked in cold water for 15, 60, and 120 min (a); soaked in hot water at different combinations of temperatures and durations (60, 70, 80 °C for 5, 10, 15 min) (b); soaked in a NaCl solution (c), and; in a citric acid solution (d) both solutions of 0.05% and 1% concentration for 30 min. For potatoes fried in a fryer, the (a) pre-treatment and soaking in water at 80 °C for 5, 10, and 15 min were applied. Untreated samples were used as a control. French fries were analyzed in terms of moisture and acrylamide content, color, and texture parameters. The pre-treatments applied reduced the acrylamide content in French fries by 4-97% when fried in the pan and by 25-47% when fried in the fryer. Acrylamide content of French fries was negatively correlated with L* parameter and moisture content and positively correlated with a* parameter. The pre-treatments applied can be used successfully by consumers to reduce acrylamide content.

Chemometric Classification of Colombian Cacao Crops: Effects of Different Genotypes and Origins in Different Years of Harvest on Levels of Flavonoid and Methylxanthine Metabolites in Raw Cacao Beans

The aim of this study was to evaluate the levels of chemical markers in raw cacao beans in two clones (introduced and regional) in Colombia over several years. Multivariate statistical methods were used to analyze the flavanol monomers (epicatechin and catechin), flavanol oligomers (procyanidins) and methylxanthine alkaloids (caffeine and theobromine) of cocoa samples. The results identified genotype as the main factor contributing to cacao chemistry, although significant differences were not observed between universal and regional clones in PCA. The univariate analysis allowed us to establish that EET-96 had the highest contents of both flavanol monomers (13.12 ± 2.30 mg/g) and procyanidins (7.56 ± 4.59 mg/g). In addition, the geographic origin, the harvest conditions of each region and the year of harvest may contribute to major discrepancies between results. Turbo cocoa samples are notable for their higher flavanol monomer content, Chigorodó cocoa samples for the presence of both types of polyphenol (monomer and procyanidin contents) and the Northeast cocoa samples for the higher methylxanthine content. We hope that knowledge of the heterogeneity of the metabolites of interest in each clone will contribute to the generation of added value in the cocoa production chain and its sustainability.

Distinguishing between Decaffeinated and Regular Coffee by HS-SPME-GC×GC-TOFMS, Chemometrics, and Machine Learning

Coffee, one of the most popular beverages in the world, attracts consumers by its rich aroma and the stimulating effect of caffeine. Increasing consumers prefer decaffeinated coffee to regular coffee due to health concerns. There are some main decaffeination methods commonly used by commercial coffee producers for decades. However, a certain amount of the aroma precursors can be removed together with caffeine, which could cause a thin taste of decaffeinated coffee. To understand the difference between regular and decaffeinated coffee from the volatile composition point of view, headspace solid-phase microextraction two-dimensional gas chromatography time-of-flight mass spectrometry (HS-SPME-GC×GC-TOFMS) was employed to examine the headspace volatiles of eight pairs of regular and decaffeinated coffees in this study. Using the key aroma-related volatiles, decaffeinated coffee was significantly separated from regular coffee by principal component analysis (PCA). Using feature-selection tools (univariate analysis: t-test and multivariate analysis: partial least squares-discriminant analysis (PLS-DA)), a group of pyrazines was observed to be significantly different between regular coffee and decaffeinated coffee. Pyrazines were more enriched in the regular coffee, which was due to the reduction of sucrose during the decaffeination process. The reduction of pyrazines led to a lack of nutty, roasted, chocolate, earthy, and musty aroma in the decaffeinated coffee. For the non-targeted analysis, the random forest (RF) classification algorithm was used to select the most important features that could enable a distinct classification between the two coffee types. In total, 20 discriminatory features were identified. The results suggested that pyrazine-derived compounds were a strong marker for the regular coffee group whereas furan-derived compounds were a strong marker for the decaffeinated coffee samples.

Quality Formation of Adzuki Bean Baked: From Acrylamide to Volatiles under Microwave Heating and Drum Roasting

Baked adzuki beans are rich in tantalizing odor and nutritional components, such as protein, dietary fiber, vitamin B, and minerals. To analyze the final quality of baked beans, the acrylamide and volatile formation of adzuki beans were investigated under the conditions of microwave baking and drum roasting. The results indicate that the acrylamide formation in baked adzuki beans obeys the exponential growth function during the baking process, where a rapid increase in acrylamide content occurs at a critical temperature and low moisture content. The critical temperature that leads to a sudden increase in acrylamide content is 116.5 °C for the moisture content of 5.6% (w.b.) in microwave baking and 91.6 °C for the moisture content of 6.1% (w.b.) in drum roasting. The microwave-baked adzuki beans had a higher formation of the kinetics of acrylamide than that of drum-roasted beans due to the microwave volumetric heating mode. The acrylamide content in baked adzuki beans had a significant correlation with their color due to the Maillard reaction. A color difference of 11.1 and 3.6 may be introduced to evaluate the starting point of the increase in acrylamide content under microwave baking and drum roasting, respectively. Heating processes, including microwave baking and drum roasting, for adzuki beans generate characteristic volatile compounds such as furan, pyrazine, ketone, alcohols, aldehydes, esters, pyrroles, sulfocompound, phenols, and pyridine. Regarding flavor formation, beans baked via drum roasting showed better flavor quality than microwave-baked beans.

HS-SPME Gas Chromatography Approach for Underivatized Acrylamide Determination in Biscuits

Acrylamide (AA) is a food contaminant in thermally processed products that is object of tight control. A simple and easy-to-apply methodology for routine monitoring of AA levels in food products could allow producers to be players in the control of their own products. In this work, a simple methodology for AA quantification without derivatization was developed for biscuits, for which the benchmark levels recommended by EFSA are 350 µg/kg, and 150 µg/kg for biscuits for infants and young children. Headspace-solid phase microextraction (HS-SPME) was used in 120 mL screwed-cap vials with a carboxen/polydimetylsiloxane fiber, 4 g of biscuits, and 10 mL of water during 15 min at room temperature under stirring. The addition of 30 mL of propanol under stirring during 15 min at room temperature and 15 min at 60 °C was used to promote AA transfer to the headspace. The fiber exposure was 45 min. A gas chromatography-mass spectrometry analysis allowed to obtain an external calibration curve at m/z 71, with linearity R² > 0.99 and precision RSD < 9%. The detection and quantification limits were 27.4 µg/kg and 91.5 µg/kg, respectively. The methodology was successfully used in biscuits with lower AA amount, where mitigation strategies (asparaginase or pectate) were applied.

Acrylamide Exposure from Common Culinary Preparations in Spain, in Household, Catering and Industrial Settings

In 2019, the European Commission recommended monitoring the presence of acrylamide in certain foods not included in Regulation 2158/2017, to consider other sources of exposure to the contaminant. In the present study, eleven groups of processed foods commonly consumed in Spain were classified, according to their food matrix, into potato-based food, cereal-based food and food based on cereal mixed with meat, fish or vegetables. Samples were collected from three different settings: household, catering services and industrial origin, to evaluate the influence of the food preparation site on acrylamide formation. The highest concentrations of acrylamide were observed in chips (French fries), especially those prepared at home. Although at lower levels, all the other foods also contained significant concentrations of acrylamide, confirming the need to control its content in foods not included in the EU regulation. Industrially processed foods made a lower contribution to acrylamide exposure, probably due to the more stringent controls exercised on culinary processes in this context. The higher levels recorded for households and catering services highlight the need for greater awareness of culinary processes and for measures to be adopted in these settings to limit the formation of acrylamide in food preparation.

Selected Instrumental Techniques Applied in Food and Feed: Quality, Safety and Adulteration Analysis

This review presents an overall glance at selected instrumental analytical techniques and methods used in food analysis, focusing on their primary food science research applications. The methods described represent approaches that have already been developed or are currently being implemented in our laboratories. Some techniques are widespread and well known and hence we will focus only in very specific examples, whilst the relatively less common techniques applied in food science are covered in a wider fashion. We made a particular emphasis on the works published on this topic in the last five years. When appropriate, we referred the reader to specialized reports highlighting each technique's principle and focused on said technologies' applications in the food analysis field. Each example forwarded will consider the advantages and limitations of the application. Certain study cases will typify that several of the techniques mentioned are used simultaneously to resolve an issue, support novel data, or gather further information from the food sample.

Roasted Rye as a Coffee Substitute: Methods for Reducing Acrylamide

Acrylamide is assumed to be a potential carcinogen, and reference values have therefore been implemented in EU legislation. Thus, the food industry needs to reduce the acrylamide content in consumer products to the lowest possible value. In this study, roasted rye was evaluated for its suitability as a coffee substitution product with respect to its acrylamide content. The influence of process modifiers, free asparagine content, storage, and rye type on the final content of acrylamide was investigated. Changes in carbohydrate composition and brightness caused by the roasting process were described. Sample analysis was conducted via GC-MS and HPLC-CAD. Existing methods were adapted to roasted rye as the sample matrix. CaCl₂ and asparaginase treatment as well as pH adjustments prior to roasting did not prove to reduce the acrylamide content. A significantly (* p < 0.027) lower free asparagine content in the raw material resulted in a lower formation of acrylamide in the final product. The acrylamide content significantly decreased (**** p < 0.0001) after 3 (1100 ± 18 µg kg⁻¹) and 6 (490 ± 7 µg kg⁻¹) months of long-term storage. Only samples stored for 6 months (490 ± 7 µg kg⁻¹) met the EU acrylamide content requirements (<500 µg kg⁻¹) for grain-based coffee substitution products.