Effect of pulsed electric field and mild thermal processing on texture-related pectin properties to better understand carrot (Daucus carota) texture changes during subsequent cooking

Abstract

Pulsed electric field (PEF) and/or mild thermal (60 °C) processing distinctly affect the texture degradation of carrot tissues during subsequent cooking. The impact of PEF and/or mild thermal processing on texture-related pectin properties was studied in terms of pectin extractability, degree of methylesterification (DM) and Ca2+ crosslinking in carrot cortex and vascular tissue. In the case of cortex tissue, the treatments significantly (α = 0.05) reduced the extractability of pectin in water and alkali; the pectin DM and ionic crosslinking were not affected. In the case of vascular tissue, mainly the PEF and combination treatment reduced the extractability of pectin in water and alkali, reduced the pectin DM (approx. 60 to 50%), and improved its ionic crosslinking. Addition of Ca2+ ions may help preserve the texture of both tissues during subsequent cooking. Further research is necessary to investigate the effect of the treatments on covalent pectin crosslinking, especially in cortex tissue.