Glycidol Fatty Acid Ester and 3-Monochloropropane-1,2-Diol Fatty Acid Ester in Commercially Prepared Foods

Effects of Heat-Cooking with Edible Fats and Oils on the Levels of 3-Chloro-1, 2-Propanediol Fatty Acid Esters (3-MCPDEs), 2-Chloro-1, 3-Propanediol Fatty Acid Esters (2-MCPDEs) and Glycidyl Fatty Acid Esters (GEs) in Processed Foods

This study investigated the effect of cooking on the levels of 3-chloro-1, 2-propanediol esters (3-MCPDEs), 2-chloro-1, 3-propanediol esters (2-MCPDEs) and glycidyl esters (GEs) in deep-fried rice cracker, fried potato, croquette, fish fillet, chicken fillet and cooking oils (rice bran oil and palm oil). The levels of 2-/3-MCPDE in rice cracker fried with rice bran oil and the used oil remained about the same, while the levels of GEs in them fell with frying time. The levels of 2-/3-MCPDEs in fried potato, croquette, fried fish and chicken cutlet fried with rice bran oil and palm oil respectively fell with frying time, while the level of GEs in them remained about the same. The levels of 2-/3-MCPDEs and GEs in fried rice cooked with rice bran oil were under the method limit of quantification. These results provide insights the cooking has no influence with the levels of 2-/3-MCPDEs and GEs in cooked foods.

Determination of chloropropanol esters and glycidyl esters in instant noodles based on solid-phase microextraction with chitosan-β-cyclodextrin coated fiber

We developed a method for the determination of chloropropanol esters and glycidyl esters (GE) in instant noodles using solid-phase microextraction with chitosan-β-cyclodextrin (CS-β-CD) coated fiber coupled with gas chromatography-tandem mass spectrometry. The developed low-cost fiber coating can improve the sensitivity of the method. Immobilized enzymes can improve operational stability and reusability compared to free enzymes, thereby reducing costs. The adsorption isotherm was modeled using the Langmuir model, while the adsorption kinetics followed the pseudo second-order model. The limit of detection was 0.3 ng/L. The method exhibited satisfactory recoveries for the analytes, ranging from 80.2 % to 105.3 %, with relative standard deviations < 9.9 %. Furthermore, the results of the exposure assessment showed that chloropropanol esters do not pose unacceptable risks to different age groups. However, the margin of exposure for GE suggested a potential health risk for populations between the ages of 3 and 12 years old.

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.

Preliminary assessments of population exposure to glycidyl esters and 3-monochloropropane-1,2-diol esters from miscellaneous oil-containing packaged foods in Taiwan

Glycidyl esters (GEs) and 3-monochloropropane-1,2-diol esters (3-MCPDEs) are carcinogenic contaminants found in refined oils. This study aimed to determine levels of GEs and 3-MCPDEs in packaged foodstuffs, and estimate daily exposure levels using food consumption data. The analysis involved Soxtec extraction and gas chromatography-mass spectrometry, and the recovery of spiked GEs and 3-MCPDEs was within the range of 80%∼110%. Results showed that GEs and 3-MCPDEs were almost ubiquitous in food products (95%), with the highest concentrations found in processed fats, followed by cookies and spreads. Food products containing palm-derived oils had significantly higher levels of contaminants (p < 0.05), with up to 58.1% of palm oil-containing foodstuffs exceeding the upper limits of either GEs or 3-MCPDEs set by the European Union. Cookies and instant noodles were identified as the main sources of exposure to GEs and 3-MCPDEs, with potential daily intake levels exceeding the tolerable daily intakes in children aged 0 ∼ 12 years.

Mitigation of 3-monochloropropane 1,2 diol ester and glycidyl ester in refined oil - A review

The 3-Monochloropropane-1, 2-diol ester (3-MCPDE) and glycidyl ester (GE) are formed at high processing temperatures with the presence of respective precursors. Both are potentially harmful to humans, causing adverse health impacts including kidney damage, reproductive problems, and increased risk of cancer. The presence of 3-MCPDE and GE in palm oil is of particular concern because of its widespread use by the food industry. There are a variety of methods for reducing 3-MCPDE and GE. For example, water washing eliminates mostly inorganic chlorides that, in turn, reduce the formation of 3-MCPDE. 3-MCPDE has also been reduced by up to 99% using combinations of methods and replacing stripping steam with alcohol-based media. Activated carbon, clay, antioxidants, potassium-based salts, and other post-refining steps have positively lowered GE, ranging from 10 to 99%. Several approaches have been successful in reducing these process contaminants without affecting other quality metrics.

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.

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.

Lipidomics Analysis Explores the Mechanism of Renal Injury in Rat Induced by 3-MCPD

3-monochloropropane-1,2-diol (3-MCPD) is a food-process toxic substance, and its main target organ is the kidney. The present study examined and characterized the nephrotoxicity and the lipidomic mechanisms in a model of kidney injury in Sprague Dawley (SD) rats treated with high (45 mg/kg) and low (30 mg/kg) doses of 3-MCPD. The results showed that the ingestion of 3-MCPD led to a dose-dependent increase in serum creatinine and urea nitrogen levels and histological renal impairment. The oxidative stress indicators (MDA, GSH, T-AOC) in the rat kidney altered in a dose-dependent manner in 3-MCPD groups. The lipidomics analysis revealed that 3-MCPD caused kidney injury by interfering with glycerophospholipid metabolism and sphingolipid metabolism. In addition, 38 lipids were screened as potential biomarkers. This study not only revealed the mechanism of 3-MCPD renal toxicity from the perspective of lipidomics but also provided a new approach to the study of 3-MCPD nephrotoxicity.

Instant Controlled Pressure Drop (DIC) Processing to Reduce 3-Monochloropropane-1,2-diol Concentration in Palm Oil

Deodorization of vegetable oils may introduce potentially carcinogenic, as well as genotoxic contaminants, generating health risks for consumers. However, the deodorization step of the refining process leads to the formation of 3-monochloro-1,2-propanediol (3-MCPD). 3-MCPD has been classified as potentially carcinogenic to humans by the World Health Organization (WHO). The purpose of this study was to optimize recently updated oil treatment techniques using Instant Controlled Pressure Drop (DIC) to improve 3-MCPD elimination in edible palm oil. Based on the central composite (CCD-DoE), response surface methodology (RSM) was developed to find the best combination of two variables at five levels to remove 3-MCPD from the palm oil. Samples of palm oil were split into two groups. The first group was treated only by the traditional method, including refining, degumming, deacidification, decolorization, deodorization, dehydration, filtration, and dewaxing processes. The second group was first treated by the traditional method, followed by the DIC technique during different periods at various temperatures and pressures. In the experiment, the effect of 3-MCPD removal in palm oil was examined by varying the oil inlet pressure and reaction time from 200 to 325 kPa and from 8.66 to 26.34 s/cycle, respectively. The 3D surface graphs showed that the optimum reduction of 3-MCPD occurs with a reaction time of 26.34s and a pressure value of 413 kPa. Samples of palm oil were analyzed using a GC-MS/MS method to determine 3-MCPD concentrations. It was found that the DIC technology reduces oil contamination with 3-MCPD when used after the traditional oil treatment process.

Association between dietary 3-monochloropropane-1,2-diol esters (3-MCPDE) and renal cancer in Peninsular Malaysia: exposure assessment and matched case-control study

3-Monochloropropane-1,2-diol esters (3-MCPDE) are food contaminants commonly found in refined vegetable oils and fats, which have possible carcinogenic implications in humans. To investigate this clinically, we conducted an occurrence level analysis on eight categories of retail and cooked food commonly consumed in Malaysia. This was used to estimate the daily exposure level, through a questionnaire-based case-control study involving 77 subjects with renal cancer, with 80 matching controls. Adjusted Odds Ratio (AOR) was calculated using the multiple logistic regression model adjusted for confounding factors. A pooled estimate of total 3-MCPDE intake per day was compared between both groups, to assess exposure and disease outcome. Among the food categories analysed, vegetable fats and oils recorded the highest occurrence levels (mean: 1.91 ± 1.90 mg/kg), significantly more than all other food categories (p < .05). Risk estimation found the Chinese ethnic group to be five times more likely to develop renal cancer compared to Malays (AOR = 5.15, p = .001). However, an inverse association was observed as the 3-MCPDE exposure among the Malays (median: 0.162 ± 0.229 mg/day/person) were found to be significantly higher than the Chinese (p = .001). There was no significant difference (p = .405) in 3-MCPDE intake between the cases (median: 0.115 ± 0.137 mg/day/person) and controls (median: 0.105 ± 0.151 mg/day/person), with no association between high intake of 3-MCPDE and the development of renal cancer (OR = 1.41, 95% CI: 0.5091-2.5553). Thus, there was insufficient clinical evidence to suggest that this contaminant contributes to the development of renal malignancies in humans through dietary consumption. Further research is necessary to support these findings, which could have significant public health ramifications for the improvement of dietary practices and food safety measures.

Potential Role of Lipase Activity on the Internal Exposure Assessment of Glycidol Released from Its Fatty Acid Esters

Glycidyl fatty acid esters (GEs) can be found in food, and they can be converted into genotoxic animal carcinogen glycidol in vivo by the action of lipase. This study examined whether human ingestion of charbroiled pork containing high levels of GEs (300 µg/day) increased glycidol-hemoglobin adduct (diHOPrVal), a marker of internal exposure to glycidol using LC-MS/MS. Contrary to expectation, the diHOPrVal value before ingesting charbroiled pork was 3.11 ± 1.10 pmol/g globin, which slightly decreased to 2.48 ± 0.47 pmol/g globin after 5 days of consumption. The decrease in lipase activity caused by the continuous consumption of lipid-rich foods such as meat in humans might decrease internal exposure to glycidol released from its esters. Thus, lipase activity was measured in C57/BL6J mice fed a high-fat diet (HFD) for 8 weeks, and diHOPrVal formation was measured after the administration of glycidyl oleate. Lipase activity was significantly lower in the HFD group than in the normal diet group. The amount of diHOPrVal was reduced in the HFD group. Therefore, the lipase activity was reduced by HFD, thereby decreasing the degradation of glycidol from glycidyl oleate. These results indicate that changes in lipase activity depending on the amount of lipids in the diet may affect the assessment of GEs exposure, and monitoring the lipase activity would provide a comprehensive understanding of exposure assessment.

Bibliometric Analysis of Research Trends on 3-Monochloropropane-1,2-Diol Esters in Foods

3-Monochloropropane-1,2-diol esters (3-MCPDE) are common food contaminants mainly formed in the edible oil refining process. Due to their potential hazards, 3-MCPDE has become a widespread food safety concern. In this study, CiteSpace and VOSviewer were used to conduct a bibliometric analysis on the 3-MCPDE research papers collected in the Web of Science Core Collection from 1998 to 2022. The results showed that the number of research publications on 3-MCPDE has increased rapidly since 2010. Analysis of the hotspots in 3-MCPDE studies showed that more attention has been paid to the exposure assessment, formation mechanism, detection methods, mitigation methods and toxicity, and toxicology of 3-MCPDE. Finally, the future trends of research on 3-MCPDE were analyzed and proposed. The mitigation methods and toxicology studies of 3-MCPDE are still the research hotspots in the future. In addition, nutritional intervention for 3-MCPDE toxicity will be an emerging trend.