Article

Inactivation of Salmonella enterica on whole tomatoes and Serrano peppers immersed in PRO-SAN, a biodegradable vegetable sanitiser

Authors:
  • University Dunarea de Jos of Galati Romania
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Abstract

There is an increasing global trend towards the use of more environmentally friendly antimicrobials in the food industry. For the present study, tomatoes and Serrano peppers, inoculated with a 5-serotype mixture of S. enterica (7.0 log 10 CFU/tomato or pepper) were immersed (for 2.0 or 4.0 min) in water (control), chlorine (150 ppm), PRO-SAN, and PRO-SAN derivative solutions (PRO-SAN-LC, PRO-SAN-soft, and PRO-SAN-PF) at concentrations of 0.1 to 1.0%. Following treatment, tomatoes and peppers were tested for viable salmonellae (at day 0, 2, 4, 6, and 8) and pH, titratable acidity (% citric acid), % BRIX and total carotenoid (mg/100 g fresh weight) content at days 1 and 7 of storage (4°C for tomatoes and 10°C for peppers). Immersion (2-min) in water and chlorine, respectively, resulted in 1.6 and 2.1 log reductions of salmonellae on tomatoes. Log reductions on peppers were 1.65 (water) and 2.47 (chlorine). Log reductions from PRO-SAN treatments ranged from 2.31 to 3.0 (for tomatoes) and 3.39 to 4.1 (for peppers). The largest reductions were consistently obtained with PRO-SAN or PRO-SAN-soft. Increasing the time of immersion from 2 to 4 min did not significantly increase inactivation of the pathogen (P >0.05). In addition, PRO-SAN and its derivatives did not adversely affect the quality parameters of tomatoes and peppers evaluated during 7 days of storage. In conclusion, PRO-SAN-based vegetable sanitisers are a good environmentally- friendly alternative to chlorine or other synthetic chemicals that might be used as sanitisers in the fresh produce industry.

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