EFF和乙醇对采后薄皮甜瓜果实贮藏品质及相关生理指标的影响

Comparative Effects of Enhanced Freshness Formulation and ethanol Treatments on Quality and Related Physiological Indexes of Postharvest Oriental Sweet Melons(Cucumis melo var. makuwa Makino) during Storage

考察促进保鲜配方(enhanced freshness formulation,EFF)和乙醇(ethanol,Eth)对采后薄皮甜瓜果实贮藏效果的影响。以东北主栽不耐贮藏薄皮甜瓜‘金妃’为试材,分别采用2%EFF浸泡和0.5 mL/kg Eth蒸熏2个方式处理采后薄皮甜瓜,以不做任何处理为对照。在15℃恒温培养箱(相对湿度85%)中贮藏16 d,测定贮藏期间果实品质特性及其相关生理指标。结果表明:两处理均显著抑制了贮藏期间甜瓜果实内源乙烯的释放量(P<0.05),且EFF较Eth效果显著,推迟了果实内源乙烯高峰的出现。贮藏期间,两处理均延缓了薄皮甜瓜果实硬度下降速率、水分损失速率及可溶性固形物的消耗;降低了果实腐烂率;保持了果实的感官品质。Eth蒸熏处理7 d之前效果较好,而EFF浸泡处理的保鲜期更长。贮藏7 d后,两处理显著抑制了可溶性果胶含量的升高速率及原果胶含量的下降速率(P<0.05);EFF处理中纤维素的下降速率明显低于Eth处理和对照;两处理均显著抑制了多聚半乳糖醛酸酶和纤维素酶活性(P<0.05),但对β-葡萄糖苷酶活性影响无明显规律。综上,两处理均延缓了采后薄皮甜瓜果实的软化速率,保持了果实品质,保鲜效果显著,且EFF浸泡的效果优于Eth蒸熏。

The purpose of this experiment was to compare the effects of soaking with enhanced freshness formulation(EFF),consisting of hexaldehyde,95% ethanol,Tween 80,ascorbic acid,etc,and ethanol fumigation on quality and related physiological indexes of postharvest oriental sweet melons(Cucumis melo var. makuwa Makino) during storage. Oriental sweet melon cultivar ‘Jinfei' universally planted in northeast China was selected as materials in this study. Harvested melons were treated by soaking in 2% EFF and 0.5 mL/kg ethanol fumigation,respectively,and those without any treatment were used as controls in this experiment. The materials were stored in incubators at 15 ℃ and a relative humidity(RH) of 85% for 16 days,during which quality attributes and related physiological indexes were measured. The results revealed that both treatments had significant inhibition on released quantity of internal ethylene in melons during storage. EFF soaking treatment had more obvious effect on postponing the peak time of internal ethylene release than ethanol fumigation treatment. Both treatments delayed the descending rate of fruit firmness and the lossing rate of water content and soluble solid content during storage. They also reduced fruit rotting rate and maintained fruit sensory quality. Before the 7th day,ethanol fumigation had better effect while EFF soaking provided relatively longer freshness lifetime. After the 7th day,both treatments had obviously inhibited the increase in soluble pectin content and the decrease in protopectin content(P < 0.05). EFF treatment significantly slowed down the decrease in cellulose content than EFF treatment than that in ethanol treatment and control. Both treatments significantly inhibited the activities of polygalacturonase and cellulase(P < 0.05),but had no obvious effects on the activity of β-glucosidase. In conclusion,both treatments can reduce softening rate and maintain fruit quality of postharvest oriental sweet melons. This study shows that both treatments are significantly effective in maintaining the freshness of sweet melons and EFF soaking is better than ethanol fumigation.