Evaluation of Alternative Preservation Treatments (Water Heat Treatment, Ultrasounds, Thermosonication and UV-C Radiation) to Improve Safety and Quality of Whole Tomato

Abstract

Previously optimised postharvest treatments were compared to conventional chlorinated water treatment in terms of their effects on the overall quality of tomato ('Zinac') during storage at 10°C. The treatments in question were water heat treatment (WHT = 40°C, 30 min), ultrasounds (US = 45 kHz, 80 %, 30 min), thermosonication (TS = 40°C, 30 min, 45 kHz, 80 %) and ultraviolet irradiation (UV-C: 0.97 kJ m −2). The quality factors evaluated were colour, texture, sensorial analysis, mass loss, antioxidant capacity, total phenolic content, peroxidase and pectin methylesterase enzymatic activities, and microbial load reduction. The results demonstrate that all treatments tested preserve tomato quality to some extent during storage at 10°C. WHT, TS and UV-C proved to be more efficient on minimising colour and texture changes with the additional advantage of microbial load reduction, leading to a shelf life extension when compared to control trials. However, at the end of storage, with exception of WHT samples, the antioxidant activity and phenolic content of treated samples was lower than for control samples. Moreover, sensorial results were well correlated with instrumental colour experimental data. This study presents alternative postharvest technologies that improve tomato (Zinac) quality during shelf life period and minimise the negative impact of conventional chlorinated water on human safety, health and environment.

Simultaneous UV-C and Ultrasonic Energy Treatment for Disinfection of Tomatoes and Its Antioxidant Properties

“…Values of the same quantum have been reported in literature, i.e. 0.75 mM Trolox kg -1 FW [37], 78.72 µM TEAC 100g -1 FW [18], 599.40 µM Trolox 100g -1 [30], 420 µM Trolox 100g -1 [43], 187.43 µmol TE 100g -1 FW [23]. Simultaneous treatment has caused an increase in antioxidant activity for all dosage applications, and to the highest values of 95.67 and 89.65 mMTE 100g -1 FW at 8.61 kJ/m 2 .…”

“…Statistical analysis showed no significant difference (p > 0.05) for both lamp configurations. This positive effect of treatment on antioxidant activity from hydrophilic extract agrees with earlier reported studies utilizing UV-C radiation [25], [30], [37], but contradicts with reports by Jagadeesh et al, 2011 [18] and Liu et al, 2011 [40] that hormetic UV-C and UV-B radiation dose had no significant effect on tomato hydrophilic antioxidant activity. Since there is a positive correlation between antioxidant activity and total phenolic content (r = 0.89 for 2 lamps and 0.93 for 4 lamps), the increase in antioxidant activity could be attributed to the increase in total phenolic contents [36], [41], [44].…”

“…Table I shows that the initial yeast and mold count for untreated samples stood at 3.36 log CFUg -1 . Previous studies have reported initial yeast and mold count of as low as 1.6 log CFUg -1 and as much as 4.69 log CFUg -1 on tomato [12], [20], [27], [29], [30]. The ripening stage of tomato sample could be responsible for the difference in yeast and mold population density as yeast and mold contamination is associated with ripeness.…”

Modelling effects of pre-storage treatments, maturity stage, low-cost storage technology environment and storage period on the quality of tomato fruit

“…Quality determination is a critical operation for the ease of processing and storability for stakeholders involved in the fresh produce industry. Measurement of quality-related attributes is the tool that can help to investigate and quality control of fresh produce at postharvest handling (Abbott, 1999;Pinheiro, Alegria, Abreu, Gonçalves, & Silva, 2016;Schouten et al, 2014;Schouten, Huijben, Tijskens, & van Kooten, 2007). Alimi, Shittu and Sanni (2014) reported that the final quality is dependent on the interaction effects of the different treatments.…”

Uso combinado de radiación UV-C y biorecubrimiento de quitosán con aceites esenciales para el control de hongos en papaya Maradol

“…Frutic., Jaboticabal, 2018, v. 40, n. 3: (e-688) Exposición a energía UV-C Se utilizó como fuente de energía UV-C (l 200-280 nm) lámpara germicida Marca Sankyo Denki Modelo G15T8. Las frutas fueron sometidas a la radiación UV-C, según el procedimiento descrito por Pinheiro et al (2016), con modificaciones. Para lograr las tres dosis preestablecidas de energía, los frutos se expusieron frente a la lámpara durante 3 min (0.97 kJ·m -2 ), 6 min (2 kJ·m -2 ) y 9 min (2.88 kJ·m -2 ) respectivamente.…”