Improving the accessibility of phytonutrients in Chlorella vulgaris through ohmic heating

Abstract

The application of electric fields, coupled with its attendant ohmic heating effect, might represent a novel approach to process microalgae biomass. When exposed to temperatures above 70 °C, depending on the duration of exposure, significant effects were observed in the release of intracellular compounds from Chlorella vulgaris cells. The most significant effects were observed when they were treated at 90 °C with a constant electric field of 225 V.cm⁻¹, resulting in a protein concentration of 108.52 ± 9.18 mg.L⁻¹. This technology offers the advantage of achieving an extremely rapid heating rate, minimizing the risk of compound degradation due to thermal effects. Additionally, some effects on the cellular structure of microalgae were identified, which can enhance the extraction of biomolecules and metabolites, thereby promoting their digestibility as a food product.