Risks for human health related to the presence of 3‐ and 2‐monochloropropanediol (MCPD), and their fatty acid esters, and glycidyl fatty acid esters in food

Occurrence of 3-monochloropropane-1,2-diol and glycidyl esters in artisanal vegetable edible oils

The safety of vegetable oils has come under intense scrutiny ever since the International Agency for Research on Cancer issued an alert on the carcinogenic properties of 3-monochloropropane-1,2-diol fatty acid esters (3-MCPDE) and glycidyl esters (GE). In this study, a total of 114 samples of artisanal palm oil (PO), palm kernel oil (PKO), and coconut oil (CO) were sourced from three regions in Ghana. The concentrations of 3-MCPDE and GE were quantified using the indirect method with gas chromatography-mass spectrometry. Subsequently, the statistical distribution functions of the concentrations of the esters were fitted using the Palisade @risk software. The relationships between the esters in the oils were determined using the Pearson correlation coefficient. The results showed no correlation (p > 0.05) between the concentrations of 3-MCPDE and GE. However, 18-60 % of the sampled PO contained 3-MCPDE above the European Commission's 2.5 mg/kg limit. In comparison, 24-35 % of the PO contained GE at levels exceeding the Commission's 1 mg/kg limit. Similarly, 25-35 % of PKO samples had GE concentrations above the limit. CO was the least contaminated oil, with little or no evidence of 3-MCPE and GE formation. Though the most frequently occurring (modal) concentrations of the esters were below the limits imposed by the Commission, it is the 95th percentile level of concentrations, especially for PO, that pose a health concern. Serious education and control must be exercised over the production of PO to enhance safety at the national and international markets.

Determination of Free Glycidol and Total Free Monochloropropanediol in Fish and Krill Oil with Simple Aqueous Derivatization and High-Performance Liquid Chromatography-Tandem Mass Spectrometry

This study introduces a novel method for detecting free glycidol and total free monochloropropanediol (MCPD) in fish and krill oil. Before analysis on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS), p-(dimethylamino)phenol was used for derivatization of these compounds, enabling the sensitive determination of these contaminants. The sample preparation procedure includes a simple, efficient pretreatment using NaCl aqueous solution extraction and C18 sorbent cleanup (for demulsification), distinguishing glycidol from MCPD under varied reaction conditions for derivatization (weak acidic and strong alkaline aqueous environments). This approach shows broad linearity from 1 to at least 256 ng·mL-1, improved sensitivity compared to standard GC-MS methods, with the limit of detection (LOD) and limit of quantification (LOQ) for MCPD and glycidol in both oil samples verified at 0.5 ng·mL-1 and 1 ng·mL-1, respectively. Different from previous HPLC-MS methods for direct detection of glycidol esters or MCPD esters, this is the first HPLC-MS method used for the detection of free glycidol and total free MCPD in edible oil. Furthermore, this method can be potentially developed for glycidol or monochloropropane diol esters, which is similar to the current official methods adopted for indirect detection of these contaminants in different food matrices. Application of this detection method to real dietary supplements (fish oil and krill oil) revealed MCPD residues in fish oil (maximum detected: 32.78 ng·mL-1) and both MCPD (maximum detected: 2767.3 ng·mL-1) and glycidol (maximum detected: 22.2 ng·mL-1) in krill oil, emphasizing its effectiveness and accuracy for assessing contamination in these supplements.

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.

Determination of chloropropanol esters and glycidyl esters in nutritional foods by gas chromatography-tandem mass spectrometry based on acid hydrolysis and solid-phase extraction

This study presents a method based on acid transesterification and the purification by solid-phase extraction (SPE) coupled with gas chromatography-tandem mass spectrometry for quantifying 3- and 2-monochloropropanediol esters (3-MCPDE, 2-MCPDE) and glycidyl esters (GE) in nutritional foods. The fat was extracted by liquid-liquid extraction with petroleum ether and diethyl ether after the sample was hydrolysed with ammonia. Then the extract was purified by a SPE cartridge filled with the aminopropyl sorbents. It was demonstrated that the optimal elution volume for 3-MCPDE, 2-MCPDE and GE greatly depended on the sample matrix and varied from 6 to 12 mL for four different kinds of food matrices. All three analytes in the sample solution could be fully collected in the first 10-12 mL of eluate. By this way, monoacylglycerols commonly present in the samples were fully removed. Therefore, the overestimation of GE quantification was effectively eliminated. The modified analytical procedure was fully validated in a single laboratory and has been recommended as a Chinese Food Safety National Standard. In addition, two derivatisation agents, heptafluorobutyrylimidazole and phenylboronic acid, were proved to be equivalent in method accuracy and precision for the quantification of three analytes.

Occurrence and risk assessment of glycidyl and 3-monochloropropanediol esters in infant formulas marketed in Taiwan

Glycidyl esters (GEs) and 3-monochloropropanediol esters (3-MCPDEs) are process contaminants commonly found in refined edible oils which are often added to infant formulas. The Taiwan Food and Drug Administration (TFDA) launched regulations for GEs in infant formulas that went into effect on 1 July 2021. To investigate levels of GEs and 3-MCPDEs in infant formula powder, 45 products were sampled and analysed during 2020-2021. The contents of GEs and 3-MCPDEs in formulas of different brands significantly varied, but their concentrations in all of the formulas complied with European Union (EU) regulations. Infant formulas containing palm oil had significantly higher 3-MCPDE levels in both extracted oils and milk powder than those without palm oil. Concentrations of GEs and 3-MCPDEs in infant formula powder and extracted oils were significantly lower in products from Europe than those from Australia and New Zealand. Infants aged 0-1 years in Taiwan who consumed only infant formula showed a margin of exposure (MoE) exceeding 25,000. Mean consumer exposures to 3-MCPDEs stayed below the tolerable daily intake (TDI), while high exposures at the 95th percentile (P95) exceeded the TDI by 1.7-fold. Herein, we present the changing trends in the risk assessment results of infant formula across various countries in the decade. Implementation of regulations and mitigation strategy effectively reduced the risk of infants being exposed to GEs and 3-MCPDEs through infant formula.

A comparison of the exposure system of glycidol-related chemicals on the formation of glycidol-hemoglobin adducts

Glycidol fatty acid esters that are present in foods are degraded in vivo to the animal carcinogen glycidol, which binds to the N-terminal valine of hemoglobin (Hb) to form N-(2,3-dihydroxypropyl)valine (diHOPrVal) adducts. The existence of other chemicals that are converted to glycidol is unknown. To determine the effect of different exposure conditions on the formation of diHOPrVal adducts, several glycidol-related chemicals (3-monochloropropane-1,2-diol; 3-MCPD, epichlorohydrin, glyceraldehyde, acrylic acid, and 1,2-propanediol) were evaluated using in vitro and in vivo (single/repeated dose) methods. In vitro, the reaction of 3-MCPD or epichlorohydrin with human Hb produced 17% and 0.7% of diHOPrVal, as compared to equimolar glycidol, respectively. Following a single administration of glycidol-related compounds to ICR mice, diHOPrVal formation was observed only in the epichlorohydrin-treated group after day 5 of exposure. After 14 days of repeated dosing, the amounts of diHOPrVal produced by epichlorohydrin and 3-MCPD in vivo were <1% of diHOPrVal produced by an equal molar concentration of glycidol. Furthermore, glyceraldehyde group produced 0.2% of diHOPrVal at the same molar concentration of glycidol equivalents, in which diHOPrVal formation could not be confirmed by the in vitro assay. The results indicate the usefulness of diHOPrVal as an exposure marker for glycidol; however, the contribution of its formation in vivo by exposure to various chemicals will be necessary to validate and interpret the results.

Optimization of water washing for mitigation of 3-monochloropropane 1,2 diol ester in palm oil physical refining process

The presence of 3-monochloropropane-1,2 diol ester (3-MCPDE) and glycidyl ester (GE) in processed palm oils is of concern, as these oils are widely used for edible purposes. The mitigation method studied here optimizes the removal of chloride through water washing of crude palm oil (CPO), to limit the formation of 3-MCPDE. The contaminant removal obtained via washing CPO supports the quantitative findings. By utilizing 5% water in the washing step, water-soluble chlorides in CPO are removed by up to 76%, resulting in a 71% reduction of 3-MCPDE to within statutory limits. In this study, a linear correlation was developed between the chloride and the corresponding 3-MCPDE with a correlation coefficient (R2) of 0.99. Using the correlations, 1.0 mg/kg of 3-MCPDE in refined, bleached and deodorized palm oil (RBDPO) will be obtained from CPO with 1.2 mg/kg chloride with 7% wash water usage. The study also showed minor GE reduction between 7 and 11% was attained after water washing.

Occurrence and Dietary Exposure of 3-MCPD Esters and Glycidyl Esters in Domestically and Commercially Prepared Food in Singapore

This study investigated the prevalence and occurrence of 3-monochloropropanediol esters (3-MCPDEs) and glycidyl esters (GEs) in domestically and commercially prepared food in Singapore and assessed the total dietary exposure for the Singaporean population. Minimal impact on the formation of 3-MCPDEs and GEs was observed from the domestic cooking methods commonly practiced in Singapore such as deep frying and stir frying. The estimated total dietary exposure to 3-MCPDEs for the Singaporean population (aged 15 to 92) was 0.982 µg/kg bw/day for general consumers and 2.212 µg/kg bw/day for high consumers (95th percentile), which accounted for 49.1% and 110.6% of the tolerable dietary intake (TDI) at 2 µg/kg bw/day by the European Food Safety Authority (EFSA). The calculated margins of exposure (MOE) for GEs based on the dietary exposure for general consumers at 0.882 µg/kg bw/day and 2.209 µg/kg bw/day for high consumers were below 10,000, indicating a potential health concern. Our study showed that the occurrence of 3-MCPDEs and GEs varied among vegetable oils, and domestic cooking methods did not significantly impact the levels of 3-MCPDEs and GEs in prepared food. The critical factor influencing the prevalence and occurrence of 3-MCPDEs and GEs was the choice of oil used for cooking, which absorbed into the cooked food. It is essential to encourage the food industry to continue its innovation on mitigation measures to control and reduce 3-MCPDEs and GEs in vegetable oil production. Consumers are advised to make informed choices on food consumption and cooking oil for food preparation to reduce their exposure to 3-MCPDEs and GEs.

Multivariate modelling analysis for prediction of glycidyl esters and 3-monochloropropane-1,2-diol (3-MCPD) formation in periodically heated palm oil

Palm oil is a vegetable oil that is widely used for cooking and deep-frying because of its affordability. However, repeatedly heated palm oil is also prone to oxidation due to its significant content of unsaturated fatty acids and other chemical toxicants such as glycidyl esters and 3-monochloropropane-1,2-diol (3-MCPD). Initially, the physicochemical properties such as colour, viscosity, peroxide, p-anisidine and total oxidation (TOTOX) of periodically heated palm oil were investigated. Chemical profiling and fingerprinting of six different brands of palm cooking oil during heating cycles between 90 and 360 min were conducted using Fourier transform infrared (FTIR) and 1H Nuclear Magnetic Resonance (NMR) metabolomics. In addition, the multivariate analysis was employed to evaluate the 1H NMR spectroscopic pattern of repeatedly heated palm oil with the corresponding physicochemical properties. The FTIR metabolomics showed significant different of the chemical fingerprinting subjected to heating duration, which in agreement with the result of 1H NMR metabolomics. Partial least squares (PLS) model revealed that most of the physicochemical properties of periodically heated palm oil are positively correlated (R2 values of 0.98-0.99) to their spectroscopic pattern. Based on the findings, the color of the oils darkened with increased heating time. The peroxide value (PV), p-anisidine value (p-AnV), and total oxidation (TOTOX) values increased significantly due to degradation of unsaturated compounds and oxidation products formed. We identified targeted metabolites (probable carcinogens) such as 3-monochloropropane-1,2-diol (3-MCPD) and glycidyl ester (GE), indicating the conversion of 3-MCPD to GE in repeatedly heated oils based on PCA and OPLSDA models. Our correlation analysis of NMR and physicochemical properties has shown that the conversion of 3-MCPD to GE was significantly increased from 180 to 360 min cooking time. The combination spectroscopic techniques with physicochemical properties are a reliable and robust methods to evaluate the characteristics, stability and chemical's structure changes of periodically heated palm oil, which may contribute to probable carcinogens development. This study has proven that combination of NMR and physicochemical analysis may predict the formation of the probable carcinogens of heated cooking oil over time which emphasizing the need to avoid certain heating cycles to mitigate formation of probable carcinogens during cooking process.

Determination of process contaminants 2- and 3-MCPD esters and glycidyl esters in palm-based glycerol by indirect analysis using GC-MS

Esters of 2- and 3-monochloropropanediol (2-MCPDE, 3-MCPDE) and glycidol (GE) are regarded as process contaminants that are found in refined vegetable oils and oil-based foods. Since glycerol is produced during fat splitting, saponification and biodiesel production, it is important to have methods for determining contaminants that might be formed during these processes. Due to the use of glycerol as a food additive, data on the presence of compounds of toxicological concern, including 3-MCPD, are of interest. This study focuses on modifying the indirect analysis of 2-MCPDE, 3-MCPDE and GE using GC-MS based on the AOCS Official Method Cd 29a-13, validating the modified method, and quantifying 2-MCPDE, 3-MCPDE and GE in glycerol. The AOCS Cd 29a-13 method was modified at the initial stage of sample preparation in which the targeted esters were extracted from glycerol by vortex-assisted extraction before sample analysis. This modification was performed based on the polarity of all compounds involved. The calibration functions for all analytes were fitted to linear regression with R2 above 0.99. Limits of detection (LOD) 0.02, 0.01 and 0.02 mg kg-1 were obtained for 2-MCPDE, 3-MCPDE and GE, respectively. Spiked glycerol with 3-MCPDE and 2-MCPDE (0.25, 0.51 and 1.01 mg kg-1) and GE (0.58, 1.16 and 2.32 mg kg-1) were used for recovery and precision measurements. Recoveries of 100-108%, 101-103%, and 93-99% were obtained for 2-MCPDE, 3-MCPDE and GE, respectively. Acceptable precision levels with relative standard deviations ranged from 3.3% to 8.3% were obtained for repeatability and intermediate precision. The validated method was successfully applied for the analysis of the target compounds in refined glycerol from commercial plants, which showed that 2-MCPDE, 3-MCPDE and GE levels in the analysed samples were below the detection limit.

Simultaneous mitigation of 3-monochloropropane 1,2 diol ester and glycidyl ester in edible oils: a review

The rising concern about the presence of 3-monochloropropane 1,2 diol ester (3-MCPDE) and glycidyl ester (GE) in food has prompted much research to be conducted. Some process modifications and the use of specific chemicals have been employed to mitigate both 3-MCPDE and GE. Alkalisation using NaOH, KOH, alkali metals or alkaline earth metals and post sparging with steam or ethanol and short path distillation have shown simultaneous mitigation of 51-91% in 3-MCPDE and of 13-99% in GE, both contaminants achieved below 1000 µg/kg. Some of the mitigation methods have resulted in undesirable deterioration in other parameters of the refined oil. When the processed oil is used in food processing, it results in changes to 3-MCPDE and GE. Repeated deep frying above 170 °C in the presence of NaCl and baking at 200 °C with flavouring (dried garlic and onion), resulted in increased 3-MCPDE. Repeated frying in the presence of antioxidants (TBHQ, rosemary and phenolics) decreased 3-MCPDE in processed food. The GE content in foods tends to decline with time, indicating instability of GE's epoxide ring.

Nutritional Value of Meals Designed for a School-Based Food Aid Program and Comparison with Similar Commercial Products: An Example of Good Practice from the DIATROFI Program

Providing meals of high nutritional value should be the principal objective of large-scale school-based food aid programs. This study aimed at highlighting the nutritional value of meals distributed in the school-based food assistance DIATROFI Program by comparing them to their commercially available counterparts. For the purpose of this study, n = 13 DIATROFI meals and n = 50 commercial products from the 2016-2017 school year, and n = 12 DIATROFI meals and n = 40 commercial products from the 2022-2023 school year were selected. The protein, carbohydrate, total sugar, dietary fiber, total fat, sodium/salt content, and fatty acid methyl ester profile of DIATROFI meals were estimated through recipe simulation and national/international food databases, and verified through laboratory analyses while the relevant information was extracted from the label for commercial products. As verified by laboratory analyses and in comparison with food labels, most DIATROFI meals had lower total fat, saturated fatty acid, and sugar content, and most had higher dietary fiber content during both years. Many recipes' nutrient profiles also improved over time. DIATROFI meals present significant advantages over available commercial products. Such tailored-made school meals can prove to be advantageous in terms of nutrition profile compared to commercially available, which have yet to be impacted by food reformulation.

Risk assessment of 3-MCPD esters and glycidyl esters from the formulas for infants and young children up to 36 months of age

Esters of 2-monochloropropane-1,2-diol (2-MCPD), 3- monochloropropane-1,2-diol (3-MCPD), and glycidol are present in infant formulas, follow-on foods and similar compositions. They arise mainly from the vegetable oil content and may cause harmful effects in consumers. The contents of these substances in formulas were determined indirectly by converting the esters to the free form, followed by derivatization and analysis by gas chromatography-tandem mass spectrometry (GC-MS/MS). The validation results demonstrate that the method had sufficient specificity and adequate accuracy. The limits of detection (LOD) and limits of quantification (LOQ) for each of 2-MCPDE, 3-MCPDE, and GE were 1.5 and 5 µg/kg, respectively. Formula intake by children up to 36 months of age was surveyed, and the data was used to assess the risks due to 3-MCPD esters (3-MCPDE) and glycidyl esters (GE). The mean exposure dose of 3-MCPDE for different age groups ranged from 0.51 to 1.13 µg/kg bw per day. The corresponding mean GE exposure ranged from 0.031 to 0.069 µg/kg bw per day. Neither mean values nor the percentile 95% values of 3-MCPDE exposure doses exceed the recommended provisional maximum tolerable daily intake (PMTDI).

Thermal Contaminants in Coffee Induced by Roasting: A Review

Roasting is responsible for imparting the main characteristics to coffee, but the high temperatures used in the process can lead to the formation of several potentially toxic substances. Among them, polycyclic aromatic hydrocarbons, acrylamide, furan and its derivative compounds, α-dicarbonyls and advanced glycation end products, 4-methylimidazole, and chloropropanols stand out. The objective of this review is to present a current and comprehensive overview of the chemical contaminants formed during coffee roasting, including a discussion of mitigation strategies reported in the literature to decrease the concentration of these toxicants. Although the formation of the contaminants occurs during the roasting step, knowledge of the coffee production chain as a whole is important to understand the main variables that will impact their concentrations in the different coffee products. The precursors and routes of formation are generally different for each contaminant, and the formed concentrations can be quite high for some substances. In addition, the study highlights several mitigation strategies related to decreasing the concentration of precursors, modifying process conditions and eliminating/degrading the formed contaminant. Many of these strategies show promising results, but there are still challenges to be overcome, since little information is available about advantages and disadvantages in relation to aspects such as costs, potential for application on an industrial scale and impacts on sensory properties.

Occurrence and risk assessment of 3-monochloropropanediols esters (3-MCPDE), 2-monochloropropanediol esters (2-MCPDE), and glycidyl esters (GE) in commercial infant formula samples from Malaysia

The presence of 3-monochloropropanediol esters (3-MCPDE), 2-monochloropropanediol esters (2-MCPDE) and glycidyl esters (GE) in infant formula products has raised serious concerns. They incorporate vegetable oils, particularly palm-based oils, which are well-known to contain large amounts of these process contaminants. An analysis was conducted on infant formula samples (n = 16) obtained from the Malaysian market to determine the levels of 3-MCPDE, 2-MCPDE and GE using gas chromatography-mass spectrometry (GC-MS). The method was validated, with a limit of quantification (LOQ) on instrument of 0.10 µg/g for all analytes. The median concentrations of 3-MCPDE, 2-MCPDE and GE in infant formula in this study were 0.008 µg/g, 0.003 µg/g and 0.002 µg/g respectively. The estimated dietary intakes calculated from consumption of infant formula show higher exposures to infants within the age group of 0 to 5 months, highest for GE (1.61 µg/kg bw/day), followed by 3-MCPDE (0.68 µg/kg bw/day) and 2-MCPDE (0.41 µg/kg bw/day) compared to the age group of 6 to 12 months. Only one sample, relating to GE exposure is a potential risk for both age groups with MOE value below 25,000.

Development of a QuEChERS method for simultaneous analysis of 3-Monochloropropane-1,2-diol monoesters and Glycidyl esters in edible oils and margarine by LC-APCI-MS/MS

A simple, fast and effective direct method based on HPLC-APCI-QqQ-MS/MS has been developed to simultaneously determine four 3-monochloropropane-1,2-diol monoesters (3-MCPDE) esterified with palmitic, linoleic, stearic, and oleic acid, and two glycidyl esters (GE) with palmitic and oleic acid in margarine and olive oil using a QuEChERS approach. Factors affecting the efficiency of the extraction process were assessed, including type and amount of salt, extraction solvent, test portion amount, and clean-up sorbent. The analytical method was validated according to Food and Drug Administration (FDA) guidelines using matrix-matched calibration with internal standards and showed good results in terms of linearity (r² > 0.9992), accuracy (80<Recovery<120%), and precision (RSD<15%). The method was successfully applied for the first time to 11 margarine samples for simultaneous analysis of 3-MCPDE and GE.

Occurrence of glycidyl esters in infant formula products on the Canadian market between 2015 and 2019

Glycidyl fatty acid esters (GEs) are processing contaminants formed during refining steps of vegetable oils. 'In vivo' hydrolysis of GEs releases potentially carcinogenic and genotoxic glycidol (2,3-epoxy-1-propanol). Occurrence of GEs in vegetable oils used for infant formula manufacturing may pose a potential health concern for formula-fed infants. Refined oils are commonly used as the main fat ingredient in formula manufacturing. For this study, different infant formula products (powders, concentrates and ready-to-feed formula products) were purchased and analysed in 2015 (35 samples) and 2019 (33 samples). Seven individual GEs were analysed by LC-MS/MS via direct approach by stable isotope dilution analysis, and total bound glycidol concentrations were calculated. Concentrations of bound glycidol in reconstituted formula reached maxima of 40.3 ng/g in the 2015 samples and 31.5 ng/g in the samples collected in 2019, with respective means of 8.7 ng/g and 6.7 ng/g. The analysed bound glycidol concentrations are comparable with concentration ranges from other studies, but are higher than observed in studies from the European market. Temporal trend data show a reduction of bound glycidol concentrations in 2019. GE concentrations were compared across different manufacturers.

Characterization of different contaminants and current knowledge for defining chemical mixtures in human milk: A review

Hundreds of xenobiotics, with very diverse origins, have been detected in human milk, including contaminants of emerging concern, personal care products and other current-use substances reflecting lifestyle. The routes of exposure to these chemicals include dermal absorption, ingestion and inhalation. Specific families of chemicals are dominant among human milk monitoring studies (e.g., organochlorine pesticides, bisphenol A, dioxins), even though other understudied families may be equally toxicologically relevant (e.g., food-processing chemicals, current-use plasticizers and flame retardants, mycotoxins). Importantly, the lack of reliable human milk monitoring data for some individual chemicals and, especially, for complex mixtures, is a major factor hindering risk assessment. Non-targeted screening can be used as an effective tool to identify unknown contaminants of concern in human milk. This approach, in combination with novel methods to conduct risk assessments on the chemical mixtures detected in human milk, will assist in elucidating exposures that may have adverse effects on the development of breastfeeding infants.

Deep-fat Frying Using Soybean Oil-based Diacylglycerol-Palm Olein Oil Blends: Thermo-oxidative Stability, 3-MCPDE and Glycidyl Ester Formation

Diacylglycerol (DAG) is commonly known as one of the precursors for the 3-monochloro-1,2-propanediol esters (3-MCPDE) and glycidyl esters (GE) formation. However, due to its health-promoting effects, its potential as alternative frying medium was examined. This study aimed to assess the frying performance of soybean oil-based diacylglycerol oil (DO) and its oil blends with palm olein (PO), in comparison with PO. Four different oil types (DO, PO, OB I (DO:PO, 1:1, w/w) and OB II (DO:PO, 1:2, w/w)) were used to fry potato chips for five consecutive days at 180℃. The formation of oxidation compounds, acylglycerol composition, 3-MCPDE and GE changes throughout the frying study were investigated. Both OB I and OB II exhibited lower oxidation compounds' formation rates than PO. Besides, significant (p < 0.05) reductions of 3-MCPDE and increments of GE levels were observed in all frying systems throughout the frying study. After 25 frying cycles, the 3-MCPDE levels in all frying oils were below 0.13 mg/kg, while the GE levels ranged from 1.51 mg/kg to 1.89 mg/kg. Despite the poorer oxidative stability of DO, its 3-MCPDE and GE levels were much lower compared to PO. In comparison to DO, the 3-MCPDE degradation and GE formation rates were enhanced and reduced, respectively with the blending of PO and DO. This study showed the potential of DO:PO oil blend in deep-fat frying application. With appropriate blending ratio of DO and PO, an alternative frying medium with enhanced nutritional value and oxidative stability could be developed.

Stable Isotope Tracer to Reveal the Interconversion between 3-Monochloro-1,2-propanediol Ester and Glycidyl Ester during the Deodorization Process

In this study, the effects of the deodorization process on the interconversion between 3-monochloro-1,2-propanediol ester (3-MCPDE) and glycidyl ester (GE) using 3-MCPDE or GE standards containing deuterium-labeled palmitic acid (*P), oleic acid (*O), or linoleic acid (*L) were examined. Deuterium-labeled 3-MCPDE or GE was added to palm oil then deodorized at 250 °C for 20, 40, or 60 min. In the 3-MCPDE-spiked palm oil, the deuterium-labeled 3-MCPDE content decreased with deodorization time. Moreover, GE containing *P or *O was detected, but there was no GE containing *L in the 3-MCPDE-spiked palm oil. In the GE-spiked oil, GE containing *O or *L decreased with deodorization time, but the content of GE containing *P did not change over the time. Furthermore, deuterium-labeled 3-MCPDE was not detected in the GE-spiked oil. These results suggest that 3-MCPDE is converted into GE and that fatty acid species bound to 3-MCPDE or GE may affect their interconversion.

Pathways to Identify Electrophiles In Vivo Using Hemoglobin Adducts: Hydroxypropanoic Acid Valine Adduct and Its Possible Precursors

Analytical methods and tools for the characterization of the human exposome by untargeted mass spectrometry approaches are advancing rapidly. Adductomics methods have been developed for untargeted screening of short-lived electrophiles, in the form of adducts to proteins or DNA, in vivo. The identification of an adduct and its precursor electrophile in the blood is more complex than that of stable chemicals. The present work aims to illustrate procedures for the identification of an adduct to N-terminal valine in hemoglobin detected with adductomics, and pathways for the tracing of its precursor and possible exposure sources. Identification of the adduct proceeded via preparation and characterization of standards of adduct analytes. Possible precursor(s) and exposure sources were investigated by measurements in blood of adduct formation by precursors in vitro and adduct levels in vivo. The adduct was identified as hydroxypropanoic acid valine (HPA-Val) by verification with a synthesized reference. The HPA-Val was measured together with other adducts (from acrylamide, glycidamide, glycidol, and acrylic acid) in human blood (n = 51, schoolchildren). The HPA-Val levels ranged between 6 and 76 pmol/g hemoglobin. The analysis of reference samples from humans and rodents showed that the HPA-Val adduct was observed in all studied samples. No correlation of the HPA-Val level with the other studied adducts was observed in humans, nor was an increase in tobacco smokers observed. A small increase was observed in rodents exposed to glycidol. The formation of the HPA-Val adduct upon incubation of blood with glycidic acid (an epoxide) was shown. The relatively high adduct levels observed in vivo in relation to the measured reactivity of the epoxide, and the fact that the epoxide is not described as naturally occurring, suggest that glycidic acid is not the only precursor of the HPA-Val adduct identified in vivo. Another endogenous electrophile is suspected to contribute to the in vivo HPA-Val adduct level.

The Formation of 3-Monochloropropanediol Esters and Glycidyl Esters during Heat-Induced Processing Using an Olive-Based Edible Oil

With the prevalence of edible diacylglycerol (DAG) oil, which is beneficial to human, the generation of 3-monochloropropanediol esters (3-MCPDE) and glycidyl esters (GE) as well as the stability of physical properties during heat-induced processing still need to be explored. In this study, the experiment used olive-based edible oil with different contents of DAG (40, 60, and 80%) to make crackers and fry chicken. They were heated at 160 and 180 °C to determine the changes in 3-MCPDE and GE, the crackers’ hardness and gumminess, and the physical properties of the oil. During baking and frying, 3-MCPDE decreased, while the content of GE slightly increased with the prolonged heating duration. Finally, 3-MCPDE and GE were lower than 1.25 mg/kg and 1.00 mg/kg, respectively. The AV increased proportionally as duration increased and POV was below 0.30 g/100 g. In general, the changes in 3-MCPDE and GE were related to the heating temperature and duration, and not significantly (p > 0.05) related to the content of DAG.

Analysis of MCPD and Glycidyl Fatty Acid Esters in Refined Plant Oils by Supercritical Fluid Chromatography– High-Resolution Mass Spectrometry

2- and 3-chloropropane-1,2-diol (2- and 3-MCPD) and their fatty acid esters (2- and 3-MCPDEs) together with glycidyl fatty acids esters (GEs) belong to a group of process-induced contaminants. They are formed in high temperature environments and most commonly occur in refined vegetable oils. Since 2021, maximum limits for GEs and 3-MCPDEs have been enforceable in the EU, and the requirement for adequate analytical methods is constantly increasing. The aim of this study was to develop an efficient method to enable a rapid determination of nine 3-MCPDEs and seven GEs in vegetable oils within a single run employing supercritical fluid chromatography coupled to high-resolution tandem mass spectrometry (SFC–HRMS/MS). Contrary to a routine gas chromatography mass spectrometry method aimed at determination of the total MCPD pool, the sample throughput when using SFC–HRMS/MS was greatly increased, as the “dilute-and shoot” approach did not require any hydrolysis and derivatization. Additionally, the pattern of natural MCPDEs was characterized. The performance characteristics of this new method met the criteria required by Commision Regulation 2019/2093 for all target analytes.

Follow-up of the re-evaluation of polyglycerol polyricinoleate (E 476) as a food additive

Polyglycerol polyricinoleate (PGPR, E 476) was re‐evaluated in 2017 by the former EFSA Panel on Food Additives and Nutrient sources added to Food (ANS). As a follow‐up to this assessment, in this opinion, the Panel on Food Additives and Flavouring (FAF) addresses the data gaps identified to support an amendment of the EU specifications for E 476. Additionally, this opinion deals with the assessment of the proposed extension of use for E 476 in edible ices and a revision of the maximum permitted level in emulsified sauces. The Panel concluded that the proposed extension of use, if authorised, would not give rise to a safety concern. Additionally, the Panel performed a risk assessment of undesirable impurities potentially present in E 476. The Panel concluded that the maximum limits in the EU specifications for the four toxic elements (arsenic, lead, mercury, cadmium) should be lowered based on actual levels in the commercial food additive E 476. The Panel also concluded that maximum limits for glycidyl esters and 3‐monochloropropanediol should be included in the EU specifications for E 476. Alternatively, the Panel recommends an amendment of the definition of E 476 to include a requirement that the fats and oils used in the manufacturing of E 476 comply with the respective EU legislation regarding suitability for human consumption. Further, the Panel recommends a modification of the definition of E 476 indicating that polyglycerol used for the manufacturing of E 476 should be produced from glycerol meeting the specifications for E 422 (Commission Regulation (EU) No 231/2012). In this case, respective specification limits for epichlorohydrin, acrolein and butanetriol would not be needed for E 476. Finally, the Panel concluded that the proposed method based on the determination of ricinoleic acid is suitable for the determination of E 476 content in food.

Critical Evaluation of Analytical Methods for the Determination of Anthropogenic Organic Contaminants in Edible Oils: An Overview of the Last Five Years

Anthropogenic contaminants, as pesticides, polycyclic aromatic hydrocarbons (PAHs) and monochloropropanediols (MCPDs), have become important to be controlled in edible oils, since their regular occurrence. In fact, alerts from the Rapid Alert System for Food and Feed (RASFF) in oils normally include these compounds. From a critical point of view, tools used to control these compounds in the last 5 years will be discussed, including sample preparation, analysis and current regulations. Extraction and analysis methods will be discussed next, being liquid-liquid extraction (LLE) and QuEChERS, with or without clean-up step, as well as chromatographic methods coupled to different analyzers (mainly mass spectrometry), the most commonly used for extraction and analysis respectively. Occurrence in samples will also be reviewed and compared with the legal maximum residue limits (MRLs), observing that 4%, 20% and 60% of the analyzed samples exceed the legal limits for pesticides, MCPDs and PAHs respectively.

Palm Oil Processing and Controversies over Its Health Effect: Overview of Positive and Negative Consequences

Palm oil is the world's most commonly used vegetable oil and extracted both from fruit and seed of palm tree. However, its high saturated fatty acid content raised controversies over consumption of the oil. Few scientific findings suggest it as a risk factor for cardiovascular disease and increased consumer's awareness over healthy diet raised claim over it. So that, this article aimed to review literatures on palm oil extraction process and its positive and negative health consequences and besides suggest strategies for healthy diet. Literature search of relevant articles was conducted by using Google scholar, PubMed, Web of science, MEDLINE, World Health Organization library online catalogue, UNICEF library, Open access thesis and dissertations published between 2009 and 2021 explored. Study reports recommend that palmitic acid from vegetable source has less effect on blood total cholesterol and low density lipoprotein cholesterol level as compared to palmitic acid from animal source. In contrary tocotrienols of palm oil lowers blood bad cholesterol level by 7-38%. Moreover, palm oil triacylglycerol arrangement does not have a cardiovascular risk and evidences from available in vitro and in vivo studies are not sufficient enough to conclude palm oil as a causative agent for cardiovascular disease. For healthy diet consumers should avoid trans fatty acids, solid and semi solid oils. Finally, further studies recommended on mitigation strategies to minimize process induced toxicants of palm oil to acceptable level.

Opinion on the re-evaluation of mono- and diglycerides of fatty acids (E 471) as food additive in foods for infants below 16 weeks of age and follow-up of their re-evaluation as food additives for uses in foods for all population groups

Mono- and diglycerides of fatty acids (E 471) was re-evaluated in 2017 by the former EFSA Panel on Food Additives and Nutrient sources added to Food (ANS). As a follow-up to this assessment, the Panel on Food Additives and Flavouring was requested to assess mono- and diglycerides of fatty acids (E 471) for its use as food additive in food for infants below 16 weeks of age belonging to food categories 13.1.1 (Infant formulae) and 13.1.5.1 (Dietary foods for infants for special medical purposes and special formulae for infants). In addition, the FAF Panel was requested to address the issues already identified during the re-evaluation of the food additive in 2017 when used in food for the general population. The Panel considered that there is no indication of adverse effects from the available animal studies at the highest dose tested and from the post marketing data. A comparison was made between the daily exposure to the sum of mono- and di-acylglycerols from breast milk and that resulting from the use of E 471 in the infant formula. The Panel noted that the resulting exposures are in the same order of magnitude. Overall, the Panel concluded that there is no reason for a safety concern when E 471 used as food additive in FC 13.1.1 and 13.1.5.1 and according to the Annex III to Regulation (EC) No 1333/2008. The risk assessment for toxic elements and impurities clearly indicated the need to lower the current maximum limits for arsenic, lead, cadmium and mercury and to include limits for glycidyl esters, 3-monochloropropane diol and erucic acid in the EU specifications of E 471.

Exogenous ethylene application on postharvest oil palm fruit bunches improves crude palm oil quality

Quality and food safety are of paramount importance to the palm oil industry. In this work, we investigated the practicability of ethylene gas exogenous application on post-harvested oil palm fruit bunches to improve the crude palm oil (CPO) quality. The bunches were first exposed to ethylene gas for 24 hr to induce abscission of palm fruits from bunches. The detached fruits were then subjected to heat treatment, mechanical extraction, clarification and drying to produce CPO. Critical quality parameters of CPO produced, that is free fatty acid, deterioration of the bleachability index and triacylglycerol showed improvement with ethylene gas treatment. Contaminant content that is phosphorus, chloride, iron, and copper also showed a reduction in the CPO derived from ethylene-treated bunches. These findings corresponded with low levels of contaminants such as 3-monochloropropane-1,2-diol esters and glycidyl esters in refined oil. The implementation strategy and practicability of this method is herein proposed and discussed. Ethylene application not only improves the CPO quality, but could potentially enhance the process sustainability of palm oil mills.

Occurrence of thermally induced glycidyl esters and 3-monochloropropane-1,2-diol esters in refined oils and pressed oils manufactured by different processes and associated with human health risks in Taiwan

Glycidyl esters (GEs) and 3-monochloropropane-1,2-diol esters (3-MCPDEs) are heat-induced contaminants mainly formed during oil refining. Information on the occurrence of these contaminants in pressed oils is still limited. In this study, 16 oilseeds pressed with a screw press and a hydraulic press had extremely low concentrations of GEs and 3-MCPDEs. Seed-roasting at high temperatures was the principal factor that significantly increased contents of GEs and 3-MCPDEs in pressed oils, in which higher precursor levels were observed. Occurrence data of GE and 3-MCPDE concentrations in refined oils (n = 25) and pressed oils (n = 26) marketed in Taiwan showed that hot-pressed oils had higher concentrations than their cold-pressed counterparts, and average concentrations of refined oils were > 10-fold higher than those of pressed oils. Risk assessment using the margin of exposure (MOE) approach indicated the presence of GEs in edible oils was of concern for food safety, especially for people who frequently use refined oils.

Development of UHPLC/Q-TOF Analysis Method to Screen Glycerin for Direct Detection of Process Contaminants 3-Monochloropropane-1,2-diol Esters (3-MCPDEs) and Glycidyl Esters (GEs)

The U.S. Food and Drug Administration’s (FDA′s) Center for Veterinary Medicine (CVM) has been investigating reports of pets becoming ill after consuming jerky pet treats since 2007. Renal failure accounted for 30% of reported cases. Jerky pet treats contain glycerin, which can be made from vegetable oil or as a byproduct of biodiesel production. Glycidyl esters (GEs) and 3-monochloropropanediol esters (3-MCPDEs) are food contaminants that can form in glycerin during the refining process. 3-MCPDEs and GEs pose food safety concerns, as they can release free 3-MCPD and glycidol in vivo. Evidence from studies in animals shows that 3-MCPDEs are potential toxins with kidneys as their main target. As renal failure accounted for 30% of reported pet illnesses after the consumption of jerky pet treats containing glycerin, there is a need to develop a screening method to detect 3-MCPDEs and GEs in glycerin. We describe the development of an ultra-high-pressure liquid chromatography/quadrupole time-of-flight (UHPLC/Q-TOF) method for screening glycerin for MCPDEs and GEs. Glycerin was extracted and directly analyzed without a solid-phase extraction procedure. An exact mass database, developed in-house, of MCPDEs and GEs formed with common fatty acids was used in the screening.

The occurrence of 3-monochloropropane-1,2-diol esters and glycidyl esters in vegetable oils during frying

3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters (GE) are processed-developed contaminants presence in vegetable oils after undergo refining process under excessive heat. Refined oils are extensively used in various frying applications, nevertheless, the reservation against their quality and safety aspects are of major concern to consumers and food industry. Realizing the importance to address these issues, this article deliberates an overview of published studies on the manifestation of 3-MCPDE and GE when vegetable oils undergo for frying process. With the modest number of published frying research associated to 3-MCPDE and GE, we confined our review from the perspectives of frying conditions, product properties, antioxidants and additives, pre-frying treatments and frying oil management. Simplicity of the frying process is often denied by the complexity of reactions occurred between oil and food which led to the development of unwanted contaminants. The behavior of 3-MCPDE and GE is closely related to physico-chemical characteristics of oils during frying. As such, relationships between 3-MCPDE and/or GE with frying quality indices - i.e. acidity in term of free fatty acid or acid value); secondary oxidation in term of p-anisidine value, total polar compounds and its fractions, and refractive index - were also discussed when oils were subjected under intermittent and continuous frying conditions.

Monochloropropanediol esters and glycidyl esters in dietary supplements based on fish oils

Dietary supplements based on fish oils might be contaminated with thermal processing contaminants, which are generated during the fish oil deodorisation. In the study, 30 samples of dietary supplements were analysed in terms of the occurrence of 3-monochloropropane-1,2-diol esters (3-MCPDE), 2-monochloropropane-1,3-diol esters (2-MCPDE) and glycidyl esters (GE). The results showed that the highest levels of 3-MCPDE (mean: 1461 µg kg^-1) as well as 2-MCPDE (mean: 357 µg kg^-1) were observed in the products containing shark liver oil. In the case of GE, they were mainly detected in the supplements including shark liver and cod liver oils. Although the results indicated that the consumption of the investigated supplements constituted no more than 1% of tolerable daily intake (TDI), the occurrence of MCPDE and GE in fish oil dietary supplements with a special attention to the origin of ester precursors should be thoroughly investigated in further studies.

Occurrence of MCPD and glycidyl fatty acid esters in standard and specialised infant formula in Denmark

Standard infant formula and specialised infant formula for medical purposes in Denmark (n = 42) were assessed for the levels of 2-MCPDEs, 3-MCPDEs, and GEs. Similar concentrations of GEs were observed in both standard and specialised powder infant formula at around 11.5 µg/kg. For 2-MCPDEs and 3-MCPDEs, significantly higher concentrations were observed in specialised products (18.0 and 49.8 µg/kg, respectively) in comparison with the standard ones (11.8 and 31.0 µg/kg, respectively). The concentration profiles also revealed discrepancies in MCPDEs and GEs concentrations not only between different manufacturers but also in terms of infant formula variety. For instance, the hypoallergenic powder formula showed twice as much MCPDEs as the normal formula variety. Exposure estimation using average contaminant concentrations in each variety suggested no potential risk of 3-MCPDEs and GEs intake for Danish infants via infant formula consumption. However, special attention is required for a few specific products where risks might occur in terms of 3-MCPDEs and/or GEs consumption.

Current Knowledge on Interspecific Hybrid Palm Oils as Food and Food Ingredient

The consumers' opinion concerning conventional palm (Elaeis guineensis) oil is negatively affected by environmental and nutritional issues. However, oils extracted from drupes of interspecific hybrids Elaeis oleifera × E. guineensis are getting more and more interest, due to their chemical and nutritional properties. Unsaturated fatty acids (oleic and linoleic) are the most abundant constituents (60%-80% of total fatty acids) of hybrid palm oil (HPO) and are mainly acylated in position sn-2 of the glycerol backbone. Carotenes and tocotrienols are the most interesting components of the unsaponifiable matter, even if their amount in crude oils varies greatly. The Codex Committee on Fats and Oils recently provided HPO the "dignity" of codified fat substance for human consumption and defined the physical and chemical parameters for genuine crude oils. However, only few researches have been conducted to date on the functional and technological properties of HPO, thus limiting its utilization in food industry. Recent studies on the nutritional effects of HPO softened the initial enthusiasm about the "tropical equivalent of olive oil", suggesting that the overconsumption of HPO in the most-consumed processed foods should be carefully monitored.

Carbohydrate-Based Fat Mimetics Can Affect the Levels of 3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters in Shortbread Biscuits

Shortbread biscuits have become one of the most desirable snacks in all population groups but due to its high fat content it is searching for new solutions of fat reduction such as the use of carbohydrate-based fat mimetics. However, the thermal processing of food containing lipids in the presence of certain carbohydrates can contribute to the formation of toxic compounds or alter its levels. Therefore, the aim of the study was to evaluate the use of inulin and pectin gels as partial fat replacers (10-40%) in classical shortbread biscuits in a view of the changes of 3-monochloropropane-1,2-diol ester (3-MCPDE) and glycidyl ester (GE) levels after baking, and also after a two-months storage. The experiment showed that the amount of inulin gel higher than 10% promoted the endogenous formation of 3-MCPDE probably due to the higher amount of Maillard products formed in the biscuits, but after two months the levels decreased and were comparable with those transferred from shortening. Pectin did not demonstrate such phenomenon, owing to the presence of bound water in gel. Glycidyl esters were partially decomposed during baking and also during storage, particularly in the samples with the addition of pectin gel, which presumably caused by low stability of GE under acidic conditions resulting from the occurrence of galacturonic acid in pectin.

Use of headspace-gas chromatography-ion mobility spectrometry to detect volatile fingerprints of palm fibre oil and sludge palm oil in samples of crude palm oil

OBJECTIVE

The addition of residual oils such as palm fibre oil (PFO) and sludge palm oil (SPO) to crude palm oil (CPO) can be problematic within supply chains. PFO is thought to aggravate the accumulation of monochloropropanediols (MCPDs) in CPO, whilst SPO is an acidic by-product of CPO milling and is not fit for human consumption. Traditional targeted techniques to detect such additives are costly, time-consuming and require highly trained operators. Therefore, we seek to assess the use of gas chromatography-ion mobility spectrometry (GC-IMS) for rapid, cost-effective screening of CPO for the presence of characteristic PFO and SPO volatile organic compound (VOC) fingerprints.

RESULTS

Lab-pressed CPO and commercial dispatch tank (DT) CPO were spiked with PFO and SPO, respectively. Both additives were detectable at concentrations of 1% and 10% (w/w) in spiked lab-pressed CPO, via seven PFO-associated VOCs and 21 SPO-associated VOCs. DT controls could not be distinguished from PFO-spiked DT CPO, suggesting these samples may have already contained low levels of PFO. DT controls were free of SPO. SPO was detected in all SPO-spiked dispatch tank samples by all 21 of the previously distinguished VOCs and had a significant fingerprint consisting of four spectral regions.

Synthesis of 2-Monochloropanol Fatty Acid Esters and Their Acute Oral Toxicities in Swiss Mice

A novel synthetic route was designed, developed, and utilized to synthesize six high-purity 2-monochloropropanediol fatty acid esters (2-MCPD esters), a group of potential processing-induced food contaminants. A chlorine atom was introduced to C-2 of a diethyl malonate molecule, which was reduced by NaBH₄ and followed by esterification using fatty acids. The reaction products were isolated and purified using silica gel columns to obtain three 2-MCPD monoesters and three diesters at about 50-54% and 56-59% yields, respectively. In addition, 2-MCPD monopalmitate and dipalmitate were examined for their acute oral toxicities in Swiss mice. The LD₅₀ values of 2-MCPD mono- and dipalmitate were greater than 5000 mg/kg body weight (BW), along with detectable nephrotoxicity and testicular toxicity. The results of this study may promote future investigation of MCPD ester toxicology and detection.

Re-evaluation of propane-1,2-diol esters of fatty acids (E 477) as a food additive

The EFSA Panel on Food Additives and Flavourings (FAF) provides a scientific opinion re-evaluating the safety of propane-1,2-diol esters of fatty acids (E 477) when used as a food additive. The Scientific Committee on Food (SCF) in 1978 endorsed the acceptable daily intake (ADI) of 25 mg/kg body weight (bw) per day, expressed as propane-1,2-diol, established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1974. No adverse effects were observed in short-term studies in rats and dogs at the highest doses tested. The Panel considered that E 477 did not raise a concern for genotoxicity. No chronic toxicity, carcinogenicity, reproductive and developmental toxicity studies with propane-1,2-diol esters of fatty acids were available to the Panel. The Panel considered that any potential adverse effect of propane-1,2-diol ester of fatty acids would be due to propane-1,2-diol, previously re-evaluated as a food additive and for which an ADI of 25 mg/kg bw per day was established. Considering the overall metabolic and toxicity database, the Panel confirmed the previously established ADI for propane-1,2-diol esters of fatty acids (E 477) of 25 mg/kg bw per day expressed as propane 1,2 diol. This corresponds to an ADI for E 477 of 80 mg/kg bw per day, based on the concentration of free and bound propane-1,2-diol amounting to a maximum of 31% as laid down in the EU specification. The Panel concluded that there would not be a safety concern at the reported use levels for E 477 because exposure estimates from the refined non-brand loyal scenario did not exceed the ADI for E 477 in any of the population groups. However, the Panel aims to explore the feasibility of establishing a group ADI for those food additives that result in an exposure to propane-1,2-diol, such as E 477, E 1520 and E 405. Additionally, the Panel will also consider performing a combined exposure assessment to propane-1,2-diol resulting from the use of these food additives. The Panel also recommended some modifications of the EU specifications for E 477.