| الوصف: |
Haliotis iris is an endemic species of abalone in New Zealand. With limited domestic market, New Zealand abalone is mainly exported in frozen, chilled and vacuum-packed forms. Pulsed electric field (PEF) is a non-thermal technology for food preservation that retains food quality attributes and nutritional value. The objective of this study was to examine the physical and chemical changes of abalone meat after 1) PEF processing at different pulse intensity levels of 0.66 kV/cm, 1.38 kV/cm and 2.00 kV/cm, 2) heat treatments at 70 °C, 80 °C and 90 °C for 15 min, and 3) PEF processing at different pulse intensity levels followed by heat treatments. Each abalone sample was cut in half, with one half used for three different PEF treatments, and the other half as non-PEF treated controls. Unheated abalone were used to compare the differences between both non-PEF treated controls and PEF treated samples before and after heat treatments. Changes in instrumental color, texture profile, free amino acids (FAAs), fatty acids (FAs) and 2-thiobarbituric acid reactive substances (TBARs) values with the different treatments were determined to evaluate the physical and chemical properties of abalone meat. In general, 0.66 kV/cm, 1.38 kV/cm and 2.00 kV/cm PEF treatments had almost no significant effects (p > 0.05) on color, texture, TBARs value, FFAs and FAs content of unheated samples compared to the non-PEF treated controls without heat treatment. On the other hand, heat treatment significantly (p < 0.05) changed meat color, as well as increased toughness and elasticity, lipid oxidation, and FAAs and saturated fatty acids (SFAs) content of non-PEF treated sample compared to the non-PEF treated control without heat treatment. Only for color analysis, foot and adductor muscles were analyzed separately because of the visual color differences of the muscles, which were deep green and off white in color respectively. Heat treatments at 70 °C, 80 °C and 90 °C of non-PEF treated control adductor muscle caused significant ... |