Keeping quality of broccoli and mushroom by Nitrous oxide treatment during storage
Park Joo-Youn and Kim Gun-Hee
Program and Abstract. 9th Controlled Atmosphere Research Conference (CA2005). Michigan State University, East Lansing, Michigan, USA. July 5-10, 2005. page36
2005
บทคัดย่อ
Keeping quality of broccoli and mushroom by Nitrous oxide treatment during storage
There is general trend of towards a continuous increase in fresh market sales ofvegetables.A lot of methods have been investigated to improve quality and shelf life during marketing.In this study, N2O gas that has been known as one of the potential gases for vegetables was used to extend the shelf life of some perishable vegetables, broccoli and mushroom.The effects of nitrous oxide (N2O) on weight loss rate, L* a* b* values, respiration rate and ethylene forming enzyme (EFE) activity of broccolis and mushrooms were examined during storage at 20ºC and 4ºC.In addition, hardness and total soluble sugars were examined.Whole broccolis were treated with different concentrations of N2O gas (N2O 60%: O2 40% and N2O 80%: O2 20%) for 24 hours and mushrooms were treated for 12 hours with same conditions.The change rates in weight loss of untreated broccoli were higher than the treated samples.Total color difference (DE) value increased during storage of all samples and treatment with 80% N2O was effective at 20ºC.Respiration rates of broccoli were reduced by 60% N2O treatment at 20ºC while those at 4ºC were not significant differences.EFE activities were inhibited by 80% N2O treatment.Water losses in the mushrooms were reduced by N2O treatment and the effect was more remarkable at 4ºC than at 20ºC.Total color difference (DE) value increased during storage of all samples.(DE) value increased during storage of all samples. (DE values ranged from 0 to higher than 2, indicating noticeable visual changes in color could be perceived at a later stage of storage.Hardness of mushroom sharply decreased throughout storage period.The lowest of hardness values was found in mushrooms placed in controls.Respiratory rates of mushrooms reduced by N2O treatment and the respiratory rates at 20ºC were much higher than those of mushrooms at 4ºC.This result was considered due to deterioration of the tissue, development of fungi and drying of mushroom by moisture loss.EFE activities were delayed or inhibited in the treatments of N2O.