Synthesis and Characterization of Glycidyl Esters of Acrylic and Methacrylic Acids for NIPU Coatings

Glycidyl acrylate (GA) and Glycidylmethacrylate (GMA) are the reaction products of the epichlorohydrin (ECH) with acrylic acid (AA) and methacrylic acid (MAA) respectively. These monomers were synthesized via two different routes i.e. direct reaction of AA and MAA with ECH and second by reaction of AA and MAA with Sodium hydroxide to form sodium salt of the acid followed by reacting with ECH. The polymerization inhibitor used was tert-butyl hydroquinone (TBHQ) and catalysts used were triethylamine (TEA) and quaternary ammonium salt. Experimental results show that first route is suitable for synthesizing GA and second route is suitable for synthesis of GMA. The catalysts also have drastic effect on the conversion to the respective glycidyl esters. The study of the effect of catalyst and polymerization inhibitor has been carried out via both routes.

Effects of Food Types, Frying Frequency, and Frying Temperature on 3-Monochloropropane-1,2-diol Esters and Glycidyl Esters Content in Palm Oil during Frying

3-Monochloropropanediol esters (3-MCPDE) and glycidyl esters (GE) have high toxicity and have drawn global attention because of their widespread occurrence in refined oils and oil-based foods. In this study, the effects of food type (potato chips and chicken breasts), frying frequency, and frying temperature on the formation of 3-MCPDE and GE in palm oil (PO) were investigated. The results showed that 3-MCPDE was formed easier in chicken breasts than potato chips. The GE content decreased in PO after it was used for frying potato chips and chicken breasts with or without NaCl. Frying frequency was an influencing factor in the formation of 3-MCPDE and the decrease in GE in PO. Frying temperature was positively correlated with GE degradation, while it had a bidirectional effect on the formation of 3-MCPDE. The formation kinetic equations indicated that 3-MCPDE and GE followed zero-order reactions in PO. The estimated activation energy (Ea) of 1,2-bis-palmitoyl-3-chloropropanediol (Pa-Pa, 41.05 kJ/mol) was lower than those of the other three types of 3-MCPDE; this is the first theoretical explanation for why PO contains more 3-MCPD than other edible oils. Among GEs, glycidyl oleate (Li-GE) was degraded more readily than other GEs.

Comparison of acid degumming methods and their influence on the formation of 3-MCPD-esters and glycidyl esters in sunflower oil deodorization

Degumming is the first stage in processing of vegetable oils, and it is aimed at removing phospholipids. The article compares the results of degumming by phosphoric and citric acids, their effects on the extraction of calcium and magnesium ions from oils, these ions being the main components of nonhydratable phospholipids. We showed the appropriateness of combining citric and succinic acids (the final content of phospholipids in oil was 0.034%, whereas it was equal to 0.048% when citric acid was used) and citric and ascorbic acids (the final content of phospholipids in oil was 0.040%). We studied the effect of acid degumming on the formation of 3-MCPD-esters and glycidyl esters. The content of glycidyl esters after degumming with citric acid and phosphoric acid was 310 g kg–1 and 200 g kg–1, respectively. After degumming with citric acid and phosphoric acid, the content of 3-MCPD-esters in the deodorized oil was 680 g kg–1 and 470 g kg–1, respectively. On the contrary, aqueous degumming does not increase the content of these esters in the deodorized sunflower oil (the content is less than 100 g kg–1) and its implementation can be recommended as one of the ways to prevent the formation of these toxic substances during deodorization.