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Green tea extract: a proposal for fresh vegetable sanitization

Abstract

Sanitization is an essential step in reducing microorganisms since it ensures product safety for consumption. Medicinal plants have been widely used for such a purpose; among these is Camellia sinensis Linnaeus., which exerts antimicrobial action. However, studies on adopting this plant for sanitizing vegetables are scarce. The current study evaluates green tea’s antimicrobial action against bacteria responsible for vegetable contamination. Green tea extracts (dry leaves and powder) at different concentrations were assessed based on the spectrum of action (1.0%, 2.5%, 5%, 7.5%, 10%), minimum inhibition concentration, and minimum bactericidal concentration (0.47%, 1.0%, 2.5%, 5%, 7.5%, 10%, 30%, 60%). A challenge test was applied to tomatoes intentionally contaminated with pathogens to evaluate green tea extracts (30% and 60%). Application of 10% green tea extract impeded the formation of inhibition zones Escherichia coli, Salmonella enterica serovar Enteritidis (S. Enteritidis), Staphylococcus aureus, and Enterococcus faecalis in 7.41 mm, 6.83 mm, 7.33 mm, and 6.58 mm, respectively. The count of S. Enteritidis adhered to surfaces of the tomatoes decreased most significantly after treatment application. Thus, based on the current results, green tea leaf extract exhibits antimicrobial action, which makes it a potential natural sanitizer.

Keywords:
sanitizers; Camellia sinensis L.; quality; antibacterial activity; fresh vegetables

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