Enhancement of water transport and microstructural changes induced by 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 Abstract 25The main aim of this work was to evaluate the effect of high intensity ultrasound 26 on drying kinetics of orange peel as well as its influence on the microstructural 27 changes induced during drying. Convective drying kinetics of orange peel slabs 28were carried out at 40 °C and 1 m/s with (AIR+US) and without (AIR) ultrasound 29 application. Drying kinetics analysis was addressed by considering diffusion 30 theory in order to identify the influence of ultrasound on water transport. Fresh, 31 AIR and AIR+US dried samples were analyzed using Cryo-Scanning Electron 32Microscopy. Results showed that drying kinetics of orange peel were 33 significantly improved by the ultrasonic application, which involved a significant 34 (p<0.05) improvement of both mass transfer coefficient and effective moisture 35 diffusivity. The effects on mass transfer properties were confirmed from 36 microstructural observations. In the cuticle surface of flavedo, the pores were 37 obstructed by the spread of the waxy components, this fact evidencing the 38 ultrasonic effects on the interfaces. The cells of the albedo were degraded by 39 application of ultrasound as it brought about large intercellular air spaces 40 facilitating water transfer through the tissue. 41

No abstract

Highlights-A combined treatment of HHP and DPCD was used to inactivate feijoa puree enzymes.-The residual activity of enzymes decreased with increasing pressure in all treatments.-The addition of CO 2 in the package enhanced the HHP inactivation of POD and PPO.-Using HHP and DPCD, lower HHP pressures may be used for a given inactivation level.1 samples were treated at 300, 450 and 600 MPa, for 5 min. Combined High Hydrostatic Pressure and Carbon Dioxide Inactivation of Pectin 40The residual POD and PPO activity decreased in the order HHP > HHPcarb > 41HHPcarb+CO2 at all pressures used. Treatments with HHP at 300 MPa increased POD 42 activity to 140 %. The residual PME activity of HHPcarb and HHPcarb+CO2 samples at 43 600 MPa (45-50 %) was significantly (p<0.05) lower than for HHP treatment (65 %). 44The simultaneous application of HHP and DPCD seems to synergistically enhance the 45 inactivation of the enzymes studied, the CO2 concentration being a key process factor.

12In order to analyze the influence of ultrasound in mass transfer phenomena during 13 drying, modeling constitutes a fundamental tool. In this work, the study of the effect of 14 power ultrasound application on drying kinetics of eggplant was addressed by using 18Experiments were carried out, at least, in triplicate for the different powers. Furthermore, 19shrinkage and sorption isotherms were also addressed in order to reach an optimal 20 description of eggplant drying. 21Drying kinetics were sped up by the ultrasonic application, moreover, the higher the showed the best agreement with experimental data, providing percentages of explained 27 variance higher than 99.9% and mean relative errors lower than 1.2% in all the cases. 28According to these results, ultrasound could be considered a potential technology to 29 improve the convective drying of eggplant.

No abstract