Modified atmosphere combined with sanitizers are a useful tool to to extend shelf life of watercress

Postharvest, poscosecha, postcosecha, berro, watercress, antioxidant capacity, phenolic compounds, microbial quality, leafy vegetables Currently in the industry of fresh salads, watercress is shown as analternative to supply gourmet products, being recognized for the highcontent of health promoting compounds such as antioxidants and phenolic compounds. The aim of this study was to evaluate different sanitizing agentssuch as chlorine dioxide (CD, 10 mg L-1), acidified sodium chlorite (ASC, 500 mg L-1) and peroxyacetic acid (PAA 90 mg L-1) as an alternative to sodium hypochlorite (SH, 100 mg L-1). Treated samples were stored under modified atmosphere packaging (MAP) for 13 days at 5?C and 95% RH. Watercress treated with SH (100 mg L-1) in a perforated bag (air atmosphere conditions) was used as a control. The evolution of psychrophilic bacteria counts during 13 days of refrigerated storage was determined in Plate Count Agar, and incubated at 5?C for 7 d. Determinations were performed in triplicate. Sensory analyses were carried out to determine the effect of all treatments on watercress quality. All treatments in MAP showed a gradual decrease in O2 levels to 3-7% and an increase in CO2 levels to 13-16% on day 13. During the storage period, MAP maintained the antioxidant levels around 2 mg of Trolox activity g-1, while watercress stored in perforated bags showed adecrease to 1 mg Trolox activity g-1 on day 13. Total phenolic activity showed a similar trend to antioxidant level, where MAP and perforated bags reached 3 and 3.9 mg gallic acid equivalent (GAE) g-1. Initial counts of psychrophiles in raw material reached 6.4 log CFU g-1. However, after one day of storage all the treatments reduced counts between 1 and 2 logarithmic units. Modified atmosphere combined with all sanitizers turned out to be a useful tool to keep bioactive compounds levels (antioxidant capacity and phenolic activity) as well as to extend shelf life of watercress stored at 5?C. Original title, authors and sources:Alternative Sanitizers Effect on Functional Parameters on Watercress Leaves (Nasturtium officinale) Stored under Modified AtmosphereM. Verdugo, M. Ospina, A.Hinojosa, C. Char, A. Machuca, VH. Escalona*Postharvest Study Center, Faculty of Agricultural Sciences, University of Chile, Santa Rosa N? 11315, La Pintana, Casilla 1004, Santiago, Chile.*vescalona@uchile.cl II ISHS International Conference on Quality Management of Fresh Cut Produce: Convenience Food for a Tasteful Life, 17-21 July 2011, Turin - Italy, FreshCut 2011The watercress salad picture is by es.123.rf.com