Essay to use hgh ozone concentrations to keep minimally processed grapes

Table grapes are very sensitive to postharvest decay. Ozone has already been proved as effective to extend shelf-life during cold storage. However, grapes are often shipped soon after harvest or usually remain in cold storage for a short time, so ozone treatment may not have enough time to be effective; moreover, ozone may be toxic to personnel if not used properly. 

A high level of ozone inside the package could be an alternative to the common antifungal treatment for minimally processed grapes, requiring a treatment time in the order of seconds. 

This study aimed to investigate the possibility of using high levels of ozone in the headspace of packages with the objective to slow down the growth of altering microorganisms while maintaining the quality of the product. 

Materials and Methods 

Table grapes (ca. 200 g) were put in a plastic tray and they were packed inside LDPE bags. 

In-package cold plasma generator prototype (SAIM Impianti srl, Fondi, Italy) was used to treat samples in order to create different levels of ozone inside the headspace of packages. 

The main quality parameters of table grapes were analyzed over the storage time.

Results

The treatment had a significant effect on the microorganisms growth without affecting most of the quality parameters. On the other hand, aroma and flavour for all the treated samples resulted lower than those of CTRL, due to the slight but consistent burnt plastic off-odor produced by the plasma treatment.

Conclusions

The creation of high inpackage ozone levels showed good results in reducing microorganisms growth in packaged table grapes. However, the presence of a distinctive off-odor in the package headspace should be better investigated (also with reference to the packaging material used) in order to reduce negative impacts of the treatment 

Sources

Application of high in-package ozone level to preserve ready to use table grapes
Giuseppe Rosiello1, Danial Fatchurrahman1, Noelia Castillejo1, Ayoub Fathi-Najafabadi1, Lucia Russo1, Raffaele Simonelli2, Maria Luisa Amodio1, Giancarlo Colelli1
1Dipartimento DAFNE, Università di Foggia, Italy 
2SAIM Impianti S.r.l., Fondi (LT), Italy 
5th International Conference on Fresh-Cut Produce: Maintaining Quality and Safety, Foggia (Italy), 3-6 June 2024, http://www.unifg.it/freshcut.2024

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https://www.frutaschampi.es/13-ideas-de-como-preparar-las-uvas-de-fin-de-ano/