EFFICACY OF NO TREATMENT TO INHIBIT BROWNING ON FRESH CUT LETTUCE TYPES

Browning of the cut surfaces of minimally processed fruit and vegetables, including on pre-cut slices of lettuce (Lactuca sativa L.), is a limiting quality factor during storage and marketing. ‘Iceberg’ lettuce slices were fumigated with nitric oxide (NO) gas at concentrations between 5 and 1000 µl L^-1 in air at 20°C for 1 to 4 h or dipped in an aqueous solution of the NO-donor compound, 2,2’- (hydroxynitrosohydrazino)-bis-ethanamine (diethylene triamine-nitric oxide; DETANO) at concentrations between 10 and 1000 mg L^-1 for 15 s to 60 min, followed by storage at 0°C in air.
The most effective treatments were fumigation with 500 µl L^-1 NO for 1 h, and dipping in 500 mg L^-1 DETANO for 5 min.
The ability of NO to inhibit the development of browning of different types of lettuces was further investigated on the cut surfaces of four fresh-cut lettuce types (‘Green Oak’, ‘Green Coral’, ‘Baby Cos’, and ‘Butter’) during storage at 5°C. The NO was applied to lettuce strips (i) by fumigation with NO gas for 2 h, (ii) by dipping in DETANO solution dissolved in 0.01 M phosphate buffer pH 6.5, or (iii) by dipping in an aqueous solution of the NO-donor compound, sodium nitroprusside (SNP). Treatment with NO gas, DETANO, or SNP inhibited the development of browning and extended the postharvest life of all four lettuce types.
The optimum treatments were dipping in 500 mg L^-1 DETANO or SNP, which resulted in an approximately 60% increase in postharvest life over untreated lettuce slices.

VII International Postharvest Symposium

J.B. Golding, R. Huque, P. Pristijono, R.B.H. Wills

lettuce strips, cut surface browning, nitric oxide, 2,2¿-(hydroxynitrosohydrazino)-bisethanamine, DETANO, postharvest life

https://doi.org/10.17660/ActaHortic.2013.1012.125