Inhibition of lipolytic reactions during wet storage of T-Isochrysis lutea biomass by heat treatment

Microalgal lipids have a huge potential in several applications such as biofuels, food and feed. However, enzymatic lipolytic reactions during we storage cause the formation of substantial amounts of free fatty acids (FFA), which give several problems for these applications. In this study, a full factorial (3(2)) design with varying time and temperature was used to optimize a heat treatment, that inactivates lipolytic enzymes in the we paste of T-Isochrysis lutea. Therefore, the FFA and lipid content were evaluated at three time points (0, 3 and 7 days) during we storage at 4 degrees C. A treatment of a least 8 min a 80 degrees C was found to inactivate the lipolytic enzymes. A second experiment elucidated that this optimal treatment had no negative impact on fatty acid composition, peroxide value, phenolic content or carotenoid content. A short heat treatment, thus, enables we storage of microalgal paste to several days at 4 degrees C.