The effects of adding “flavour enhancers” on levels of chloropropanediol esters and glycidyl esters in savoury shortbread

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.

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.

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.

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.