Effects of innovative technologies on quality and shelf life of tomatoes

It is well known fact that there is an increase in the microbial load of tomatoes, taking place an important role in diet, from harvest to process. Increased microbial load cause problems during processing, and adversely affects the shelf life of the product. In order to decrease microbial load on tomato surface and increase the shelf life; ozone (O1 and O2), alkaline electrodialyzed water (AEW1 and AEW2) and different combination of two processes (O1+AEW1, O1+ AEW2, O2+ AEW1, and O2+ AEW2) were applied in the study. Effects of these processes on pH, oBrix, titratable acidity (TA), conductivity, color (L*, a* and b*), hue (ho), chroma (C*), total color difference (ΔE), total antioxidant capacity (TAC), total phenolic substance content (TPSC), total lycopene content (TLC), and inactivation of total aerobic mesophilic bacteria (TAMB), total mold and yeast (TMY), Salmonella Enteritidis, Listeria monocytogenes and Botryritis cinerea were investigated in the study. O2 applications caused a significant difference on the outer shell for L*, a*, b* values, C*, ho and ΔE. Generally, O1 + E1 applications can succesfully be applied to tomato pulp without any change in L*, a*, b*, ∆E values and C*, ho and browning index values. While applications did not cause significant changes on TA and pH values; significant difference was observed after applications for conductivity and oBrix value. O2, AES1+O2, O2+AES1, and AES2+O1 applications were effective to reduce initial TAMB count compare to other applications whereas the mean initial TMY was completely inactivated after O2 and O1+AEW1 applications. The mean initial numbers of L. monocytogenes, S. Enteritidis and B. cinerea were significantly inactivated by all applications includes ozone. While control samples had a shelf life of 4 weeks at 4 °C storage, other applications increased shelf life to 5 weeks except for O1 + AEW2 application. Therefore, it is suggested that ozone and their combinations can be used for shelf-life extension of tomatoes without adversely affecting its quality parameters, but sensory properties and cost preferability need to be evaluated by the consumers.