Osmodehydration assisted by ohmic heating/pulse vacuum in apples (cv. Fuji): retention of polyphenols during refrigerated storage

Abstract

Summary Apples are a widely consumed fruit and have a high polyphenol content. The aim of this study was to analyse the combined effects of osmotic dehydration (OD) and ohmic heating (OH) with a pulsed vacuum (PV) on polyphenol retention during the stored refrigeration of apple cubes. Treatments were performed using a 65°Brix sucrose solution at 30, 40 or 50 °C for 120 min, and then, samples were stored for 28 days at 5 °C. OH provides an electric field of 13 V cm−1, and a pulsed vacuum was applied for 5 min at the beginning of the process. The results indicated that a lower temperature process (30–40 °C) resulted in the retention of more polyphenol compounds after treatment than a higher temperature process (50 °C). Nevertheless, during refrigerated storage, we observed that 50 °C preserved these compounds better due to polyphenol oxidase inactivation. PVOD/OH treatment at 50 °C was determined to be the best retention of polyphenols from the fresh apple for dehydrating apples.

Application of Ohmic–Vacuum Combination Heating for the Processing of Senior-Friendly Food (Multiphase Food): Experimental Studies and Numerical Simulation

“…An increase in vacuum intensity had a great effect on the change in hardness of solid particles. This result is consistent with the previous studies showing that the firmness of papaya treated by vacuum the firmness was reduced compared to the atmospheric pressure treatment [ 40 , 41 , 42 , 43 , 44 ]. However, vacuum pretreatment time was not significant to change the hardness of solid particles.…”

Quality of ‘Royal Gala’ cut apple during osmotic dehydration

“…The highest ΔE corresponds to the highest changes in L* (results not shown), both at atmospheric pressure and in vacuum. Neri et al (2016) and Moreno et al (2017) explained that the L* parameter decreased more in OD in vacuum than at atmospheric pressure, because of the total or partial air-to-solution replacement in the sample pores that occurred with vacuum impregnation, at pressures below 857 mbar. There was an increase in ΔE at 60 °C, probably due to Maillard reactions, which are more intense at higher temperatures and lower w a (until approximately 0.8) (Fennema, 1996).…”

Optimization of ohmic heating assisted hydrodistillation of cinnamon and bay leaf essential oil

“…Ohmic heating technology has supremacy over the conventional methods in terms of uniformly heating, improving food quality, diminishing energy consumption and cost, advancing energy efficiencies, making it possible to heat food quickly (Hashemi et al, 2019; Knirsch et al, 2010; Varghese et al, 2014). Some ohmic heating applications were done successfully including blanching (Allali et al, 2010), evaporation (Cokgezme et al, 2017), dehydration (Moreno et al, 2017), fermentation (Gavahian & Tiwari, 2020), extraction (Aamir & Jittanit, 2017; Saberian et al, 2017), sterilization (Choi et al, 2015; Mesías et al, 2016), pasteurization (Achir et al, 2016; Cho et al, 2017) and thawing (Icier et al, 2017; Liu et al, 2017). OAHD, combination of ohmic heating and hydrodistillation, is also an area researchers are interested in (Gavahian et al, 2020; Gavahian & Farahnaky, 2018; Hashemi et al, 2019; Taban et al, 2018).…”