Low-oxygen treatment for inhibition of decay and ripening in organic bananas

Application of a low-O-2 atmosphere for several days prior to storing organ ic banana clusters was effective in preventing decay development on the cro wn cuts, and in delaying ripening. Preclimacteric banana clusters (Musa spp . AAA group cultivar Ziv) were treated with a low-oxygen atmosphere (2%) at 20 degreesC for 24, 48 and 72 h immediately after harvest. After removal f rom low-O-2 stress, the bananas were stored at 12 degreesC for 21 d, and we re then treated with ethylene at 18 degreesC for 24 h and transferred to sh elf life at 20 degreesC for an additional 4 d. The low-O-2 treatments were compared with the commercial treatment of dipping the crown cuts in 0.2% th iabendazole (TBZ). The low-O-2 stress for 48 or 72 h was effective in preve nting decay after shelf life, but less so than the TBZ treatment. Low-O-2 f or 24 h was not effective enough, and the 72 h treatment markedly impaired colour development after ripening with ethylene. The 48 h low-O-2 treatment which resulted in the best decay prevention also retarded ripening process es (colour, firmness, respiration and ethylene production) and reduced chil ling injury symptoms, without impairing the taste. The level of reducing su gars in the 48 h-treated fruit was similar to that in the control fruit aft er ripening and shelf life. The endogenous levels of acetaldehyde (AA) and ethanol produced by the treated fruit were lower than those in the control fruit during shelf life. It seems that there is a high potential for this p hysical treatment Of low-O-2 stress to replace chemical treatments, as mean s of maintaining the quality of organic bananas.