Alternative Sanitization Methods For Minimally Processed Lettuce In Comparison To Sodium Hypochlorite.

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.44673-

Effectiveness of different concentrations of ozonated water in the sanitization of fresh-cut green pepper

Green pepper is a popular vegetable in Brazil.  It is consumed mainly in raw salads or their complements, and therefore should be given special attention as to sanitization.  Sodium hypochlorite is currently the sanitizer most used for this purpose, but the formation of by-products is an inconvenience.  Thus, the search for techniques to minimize and/or replace this product in the fresh-cut industry has been increased.  Ozonated water can be an alternative because it is a potent sanitizer and does not create by-products.  The aim of this work was to define the most effective concentration of ozonated water in reducing microbial contamination of fresh-cut green pepper.  The raw material was purchased in a local trade of Campinas-SP, selected and minimally processed.  The sanitization consisted of immersion in tap water (T2) and ozonated water at concentrations of 1.6 mg/L (T3), 1.8 mg/L (T4) for one min.  The processing consisted of washing, manual cutting, taking up the stalk and the internal parts and slicing into strips (± 3 mm in thickness).  The control treatment (T1) was the product minimally processed without washing. The ozone concentration was measured by a commercially available kit (CHEMetrics, Vacu-vials, Ozone K-7402, Calverton, Va., U.S.A.).  It was performed physical-chemical (pH and soluble solids) and microbial analysis (mesophilic and psychrotrophic aerobic bacteria, total coliforms, Escherichia Coli, yeasts and molds, besides the presence of Salmonella spp.).  The average initial contamination of samples were 1.3×105 CFU/g to mesophilic aerobic bacteria, >1.1×103 CFU/g to total coliforms

Alternative sanitization methods for minimally processed lettuce in comparison to sodium hypochlorite

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 ºC 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.67367