title: Alternative sanitization methods for minimally processed lettuce in comparison to sodium hypochlorite.
abstract: Lettuce is a leafy vegetable widely used in industry for minimally processed products, in which the step of sanitization is the crucial moment for ensuring a safe food for consumption. Chlorinated compounds, mainly sodium hypochlorite, are the most used in Brazil, but the formation of trihalomethanes from this sanitizer is a drawback. Then, the search for alternative methods to sodium hypochlorite has been emerging as a matter of great interest. The suitability of chlorine dioxide (60 mg L(-1)/10 min), peracetic acid (100 mg L(-1)/15 min) and ozonated water (1.2 mg L(-1)/1 min) as alternative sanitizers to sodium hypochlorite (150 mg L(-1) free chlorine/15 min) were evaluated. Minimally processed lettuce washed with tap water for 1 min was used as a control. Microbiological analyses were performed in triplicate, before and after sanitization, and at 3, 6, 9 and 12 days of storage at 2 ± 1 °C with the product packaged on LDPE bags of 60 μm. It was evaluated total coliforms, Escherichia coli, Salmonella spp., psicrotrophic and mesophilic bacteria, yeasts and molds. All samples of minimally processed lettuce showed absence of E. coli and Salmonella spp. The treatments of chlorine dioxide, peracetic acid and ozonated water promoted reduction of 2.5, 1.1 and 0.7 log cycle, respectively, on count of microbial load of minimally processed product and can be used as substitutes for sodium hypochlorite. These alternative compounds promoted a shelf-life of six days to minimally processed lettuce, while the shelf-life with sodium hypochlorite was 12 days.
authors: Laboratório de Tecnologia Pós-colheita, Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors: Mara Lígia Biazotto
authors: ML
authors: Bachelli
authors: Laboratório de Tecnologia Pós-colheita, Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors: Rívia Darla Álvares
authors: RD
authors: Amaral
authors: Laboratório de Tecnologia Pós-colheita, Faculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors: Benedito Carlos
authors: BC
authors: Benedetti
mesh_terms: D058491:Bacterial Load; D001938:Brazil; D017606:Chlorine Compounds / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods*; D004755:Enterobacteriaceae / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D061353:Food Storage; D018545:Lactuca / Q000382:microbiology*; D010087:Oxides / Q000494:pharmacology*; D010126:Ozone / Q000494:pharmacology*; D010463:Peracetic Acid / Q000494:pharmacology*; D012475:Salmonella / Q000302:isolation & purification; D012973:Sodium Hypochlorite / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors
chemical_list: D017606:Chlorine Compounds; D004202:Disinfectants; D010087:Oxides; D010126:Ozone; C025109:chlorine dioxide; D012973:Sodium Hypochlorite; D010463:Peracetic Acid
keywords: chlorine dioxide; food safety; minimal processing; ozone; peracetic acid