Triacylglycerols (TAGs) can be modified to increase the absorption of fatty acids, prevent obesity, and treat fat malabsorption disorders and metabolic diseases. Medium-long-medium (MLM)-type TAGs, which contain medium-chain fatty acids in the sn-1 and sn-3 positions of the glycerol backbone and a long-chain fatty acid in the sn-2 position, show particularly interesting nutritional characteristics. This study aimed to synthesize MLM-type TAGs by enzymatic acidolysis of grape seed oil with medium-chain capric acid (C10:0) in associated packed bed reactors. The reaction was carried out during 120 H, at 45 °C, using lipase from Rhizomucor miehei (Lipozyme ® RM IM). The residence time distribution of reagents in the reactor was quantified to evaluate the reactor behavior and to diagnose the existence of preferential paths. The reaction progress was monitored by analyzing TAG composition and, at the steady state (after 48 H of reaction), the incorporation degree achieved a value of 39.91 ± 2.77%. To enhance the capric acid incorporation, an acidolysis reaction in associated packed bed reactors was performed. The results showed a good operational stability of the biocatalyst, revealing values of half-life 209.64 H, 235.63 H of packed bed and associated packed bed reactor, respectively, and a deactivation coefficient 0.0061 H −1 .

The hydrodynamics of airlift bioreactors, which offer an interesting alternative to conventional stirred-tank bioreactors, has generally been evaluated using experimental approaches, requiring time, energy, and reagents. However, computational fluid dynamics (CFD) has emerged as an important and valuable tool for the analysis and design of these devices, saving time and experimental effort, while providing a large amount of information. In this study, four geometries of a square cross-section 10-L split airlift bioreactor operating with distilled water were simulated using CFD, and the hydrodynamics variables gas hold-up and liquid velocity were evaluated. CFD satisfactorily predicted the hydrodynamic parameters, when compared to experimental data, allowing adequate prediction of the shear rate distribution in airlift bioreactors. The results indicated that different shear rate distributions were obtained by geometric modifications in the bioreactor, showing that its design should be considered to satisfy different specific bioprocess requirements.

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