Impact of pulsed light treatments on antioxidant characteristics and quality attributes of fresh-cut apples

Abstract

The effects of pulsed light (PL) treatments combined with a quality-stabilizing dip on the quality and antioxidant attributes of fresh-cut 'Golden delicious' apples was studied. Apple wedges were dipped into a solution of 1% w/v N-acetylcysteine and 0.5% w/v CaCl 2 and flashed with broad-spectrum light with an overall radiant exposure of 4, 8, 12 and 16 J. cm-2. General microbial counts, color, firmness, phenolic compounds and vitamin C contents were evaluated over 15 days at 5 ºC. More pronounced reductions of the naturallyoccurring microbiota were observed as the applied PL-dose increased. The qualitystabilizing pre-treatment effectively prevented browning phenomena on the cut-tissue surface. In addition, browning and oxidation were not promoted in PL flashed samples. Indeed, the initial contents in phenolic compounds and vitamin C were even better maintained than in untreated samples. Treatments of 8 and 16 J cm-2 were most effective for maintaining the quality and antioxidant characteristics.

Control of browning of minimally processed mangoes subjected to ultraviolet radiation pulses

“…M at 14 days). The changes that occur in compounds of phenolic origin have been reported in several minimally processed fruits and may have irregular behavior during storage (Llano et al 2015).…”

“…Beyond replacing the chemical compounds of chlorine, this technique has other advantages, such as induction of the synthesis of phenolic compounds, which act as antioxidants in vegetables . Increase in the concentration of phenolic compounds was observed in tomatoes (Bravo et al 2012) and in minimally processed apples (Llano et al 2015) exposed respectively to the ultraviolet radiation applied continuously (UV C ) and through pulses (UV P ).…”

Packaging aspects for processing and quality of foods treated by pulsed light

“…Transmissions were observed at 260 nm, since most of the microbial inactivation occurs at approximately this wavelength, and the authors recommended the PP film for the PL treatment due to greater light transmission. Avalos et al (2016) highlighted the transmittance of the PP film, of 64 μm thickness, used to treat apples by the PL treatment (higher than 97% for incident UV radiation, and about 100% for visible radiation, representing 85% of the incident energy-corresponding to wavelengths ranging between 200 and 320 nm), which is why fresh-cut apple slices were exposed to in-package PL treatments. Thus, the authors emphasized the importance of characterizing this property in such a way to have a well-dimensioned process.…”

“…Since these technologies have different operating mechanisms, their effect on packaging is usually different as well. Some of the authors who carried out studies based on this approach are described next: for high-pressure processing (Guillard et al, 2010;Juliano, Koutchma, Sui, Barbosa-Cánovas, & Sadler, 2010;Koutchma et al, 2010;Marangoni Júnior, Alves, et al, 2020;Marangoni Júnior, De Oliveira, Bócoli, et al, 2020;Marangoni Júnior, De Oliveira, Dantas, et al, 2020;Marangoni Júnior, Cristianini, Padula, & Anjos, 2019;Mensitieri, Scherillo, & Iannace, 2013;Richter, Sterr, Jost, & Langowski, 2010), for plasma treatment (Misra, Yepez, Xu, & Keener, 2019;Pankaj et al, 2014;Tyuftin & Kerry, 2020), for ultrasound treatment (Guillard et al, 2010;Ščetar, Kurek, Jambrak, & Galic, 2017;Ščetar, Kurek, Režek, & Frédéric, 2019), for ozone treatment (Guillard et al, 2010), for UV light treatment (Guillard et al, 2010;Tyuftin & Kerry, 2020), and for pulsed light (Ansari & Datta, 2003;Avalos, Marsellés-fontanet, Martín-belloso, & Soliva-fortuny, 2016;Heinrich, Zunabovic, Bergmair, Kneifel, & Jäger, 2015).…”

Recent findings in pulsed light disinfection

“…) or by Avalos Llano et al . () for fresh‐cut apples. These variable results underline the importance of specific microbial storage trials, thereby most suitably assessing native microbial populations, which due to their adaption usually show a different behaviour compared to inoculated micro‐organisms on produce surfaces after PL exposure during storage.…”