Lipozyme IM-catalyzed interesterification for the production of margarine fats in a 1 kg scale stirred tank reactor

Abstract

Lipozyme IM-catalyzed interesterification for the production of margarine fats in a 1 kg scale stirred tank reactorLipozyme IM-catalyzed interesterification of the oil blend between palm stearin and coconut oil (75/25 w/w) was studied for the production of margarine fats in a 1 kg scale batch stirred tank reactor. Parameters such as lipase load, water content, temperature, and reaction time were investigated. The reusability of Lipozyme IM was also studied under optimized conditions. The interesterification products were monitored by analysis of triacylglycerol profiles, the contents of diacylglycerols, free fatty acids (FFA), and solid fat contents. The contents of some triacylglycerol species, which were categorized by equivalent carbon number (ECN), namely ECN34, 36, 48, and 50, decreased by 6.0, 5.9, 5.8, and 13.7%, respectively, after enzymatic interesterification, similar to the reduction of those species after chemical interesterification, 6.6, 6.0, 7.1, and 12.9%, respectively. On the other hand, those of ECN38, 40, 42, 44, and 46 increased by 1.1, 1.6, 6.8, 16.7, and 6.5%, respectively, in comparison with the increase of those species after chemical interesterification, 0.2, 1.5, 6.5, 17.0, and 9.2%, respectively. Lipase load and reaction time had great influence on the degree of interesterification. A Lipozyme IM load of 6% was required for a reaction of 6 h and at 60°C, to reach a stable degree of interesterification. Temperature variation in the range of 50-75°C did not affect the reaction degree as well as the contents of diacylglycerols, but the content of FFA slightly increased with higher temperature. Addition of water to the enzyme increased the contents of diacylglycerols and FFA in the products linearly. However, it had no effect on the degree of interesterification for the first batch when the enzyme was reused. Lipozyme IM was stable in the 10-batch test after adjusting the water content in the system. The relationship between the content of water in the system and that of FFAs in the products was evaluated and discussed. * The molecular weight of the oil blend was calculated as 249.57 g/mol and the enzyme load was 10%.

Development and application of triglyceride‐based polymers and composites

“…The enzyme retained almost complete activity for three cycles and this stability may be due to immobilization and low water content. The ability of immobilized lipase to retain its synthetic activity during recycling has been confirmed in previous studies 44, 45…”

The evolution of enzymatic interesterification in the oils and fats industry

“…The ion exchange resinbased enzyme products do not suffer to the same extent from this problem. Zhang et al [11] describe the use of a Rhizomucor miehei lipase immobilised onto an ion exchange resin for the production of margarine fats. They used the enzyme for 10 batch reactions to interesterify a blend of palm stearine and coconut oil and observed that the enzyme was able to retain enough water within the granulate to carry out sequential reactions without the need to add further amounts of water.…”

Production of structured lipids with functional health benefits

“…Temperature normally affects lipase activity. Lipase-catalysed interesterification involves water and is accompanied by the formation of new TAG products as well as DAG and FFA by-products (Zhang et al, 2000;2001). However, very high operating temperatures deactivate the enzyme owing to its temperature-labile protein nature (Godfrey and West, 1996).…”

“…High temperature usually increases the initial reaction rate. The optimal water content is highly dependent on the carrier types for some enzymes (Zhang et al, 2000;2001), or dependent on the solvents used for others (Gorman and Dordick 1992). The optimal temperature is decided mainly based on the properties of feedstock, such as melting behaviour at different temperatures Interesterification degree (%) DAG (wt%) and FFA (wt%) (Zhang et al, 2001) and reaction system, that is with solvent (Fomuso and Akoh, 1998) or solvent-free (Xu et al, 2002).…”

“…However, very high operating temperatures deactivate the enzyme owing to its temperature-labile protein nature (Godfrey and West, 1996). Reusing Lipozyme RM IM without adjusting the amount of water in the reaction system leads to decreasing reaction activity (Zhang et al, 2000). Water effects.…”