1-MCP对嘎拉苹果呼吸、乙烯产生及贮藏品质的影响

以嘎啦苹果为试材,研究了0℃贮藏期间贮藏30、60、90、120d后转入货架期间1-MCP(1-甲基环丙烯)对果实呼吸速率、乙烯产生速率、硬度、可滴定酸含量及可溶性固形物含量的影响。结果表明,在0℃贮藏条件下,与对照相比,500nL/L浓度的1-MCP可以显著抑制贮藏期间果实呼吸速率和乙烯产生速率,延缓果实硬度和可滴定酸含量的下降,但对可溶性固形物含量无影响;货架期间1-MCP对果实呼吸速率和乙烯产生速率同样有显著的抑制作用,也延缓果实硬度和可滴定酸含量的下降,而对可溶性固形物含量无影响。这些结果表明1-MCP在嘎拉苹果贮藏中具有很好的应用前景。     

1-MCP和不同强度减压处理对‘富士’苹果贮藏品质的影响

研究了‘富士’苹果分别在0.00、-0.02、-0.04、-0.06MPa的大气压下处理5min,1-MCP熏蒸24h,(-1±1)℃贮藏210d的品质变化。结果表明:1-MCP和减压处理可以减缓果肉硬度下降,可以有效抑制‘富士’苹果可滴定酸、可溶性固形物含量的下降,显著抑制果实乙烯释放量,显著降低呼吸速率,保持了其贮藏期的品质,延缓其衰老速率。在供试的5个负压条件中,以-0.06MPa压强处理效果最佳。     

1-MCP、薄膜包装和乙烯吸收剂对‘安哥诺’李长期冷藏期间品质和褐变的影响

果肉软化和褐变是李果实长期冷藏时的主要问题。以‘安哥诺’李为材料,采用1-MCP(0.5μL.L-1)、薄膜(30μm厚)包装(MAP)及包装内加入乙烯吸收剂(EA)的方法,研究了0℃冷藏期间‘安哥诺’李品质、褐变及其生理生化的变化。结果表明,与对照(未进行处理)相比,1-MCP、MAP和MAP+EA及其组合处理延缓了果肉软化,抑制可溶性固形物(SSC)和花青苷含量上升,保持果肉较高的白度指数,降低果肉褐变度、酚含量和多酚氧化酶(PPO)活性,1-MCP+MAP+EA的复合处理效果最佳。这些说明,采后进行1-MCP、MAP和EA的复合处理能有效抑制果肉软化和褐变,改善了果实贮藏品质。     

低温贮藏对‘金红’苹果能量代谢和品质的影响

为探究不同贮藏温度对‘金红’苹果果实能量代谢和生理品质的影响，将‘金红’苹果分别放置在–2、0、2、4 ℃条件下贮藏，定期测定果实能量相关物质三磷酸腺苷（ATP）、二磷酸腺苷（ADP）、磷酸腺苷（AMP）含量和能荷（EC）变化以及H+-ATPase、Ca2+-ATPase、琥珀酸脱氢酶（SDH）、细胞色素氧化酶（CCO）、超氧化物歧化酶（SOD）等相关酶活性，同时测定果实呼吸速率、乙烯释放速率、果实硬度、维生素C、可滴定酸、可溶性固形物含量等生理品质指标，并调查果实组织褐变情况。结果表明：整个贮藏及货架期，–2 ℃下的果实ATP、ADP和AXP（AXP = ATP + ADP + AMP）含量、EC以及能量相关代谢酶活性（H+-ATPase、SDH、CCO）、SOD、乙烯释放速率始终保持最低，维生素C含量后期下降迅速；4 ℃下的果实硬度、可溶性固形物含量和可滴定酸含量降幅较大；–2 ℃下的果实褐变指数最高（果皮和果肉均出现了严重褐变），0 ℃下的果实果皮和果肉也有轻微褐变，2 ℃和4 ℃果实无褐变。贮藏30、45、90 d以及贮藏90 d + 货架3 d和90 d + 货架5 d期间，2 ℃贮藏的果实保持较高的能量水平，果实品质和风味保持较好，0 ℃果实次之。研究结果表明，‘金红’苹果组织褐变与能量亏缺有密切关系，能量亏缺越多，褐变越严重，适宜的低温能维持果实较高的能量水平，同时抑制果实褐变，维持果实较好的贮藏品质，延缓果实衰老。     

常温贮藏条件下1-MCP处理对欧洲李子采后生理及品质的影响

以欧洲李子(Prunus domestica‘Hanita’and‘Elena’)为试材,研究了1-甲基环丙烯(1-methlcyclopropene)对欧洲李子果实采后生理和贮藏品质的影响。结果表明:在低温(3℃)下采用浓度为1.25μL/L的1-MCP对欧洲李子果实进行处理18h后,在常温贮藏过程中,‘Hanita’属于呼吸跃变型果实,而‘Elena’呼吸速率变化不大,属于非呼吸跃变型果实。1-MCP处理可以降低‘Hanita’果实呼吸高峰的峰值,有效地抑制乙烯释放量。但1-MCP处理对欧洲李子‘Hanita’和‘Elena’果实的可溶性固形物含量及可滴定酸含量的变化无影响。     

1-MCP处理对‘红阳’和‘徐香’猕猴桃保鲜效果的影响

以‘红阳’和‘徐香’猕猴桃为试材,研究了不同浓度的1-MCP处理对猕猴桃保鲜效果的影响。结果表明:1-MCP能够显著降低猕猴桃低温贮藏过程中呼吸速率、乙烯释放速率,延缓果实硬度、可滴定酸的下降以及前期可溶性固形物的上升。各处理浓度的猕猴桃均能正常后熟,但处理效果存在差异,浓度为0.50 mL/L 1-MCP处理对‘红阳’保鲜效果好,‘徐香’适宜的1-MCP处理浓度为0.25μL/L。     

1-MCP处理对‘亚特’猕猴桃果实采后生理和贮藏品质的影响

以‘亚特’猕猴桃为试材,研究了1-MCP处理对果实采后生理和贮藏品质的影响.结果表明:1-MCP处理能够抑制猕猴桃果实采后乙烯释放速率和呼吸速率的增加,推迟果实乙烯和呼吸峰出现的时间,降低乙烯和呼吸峰值;抑制猕猴桃果实硬度和淀粉含量的下降,延缓可溶性固形物和葡萄糖含量的上升速度,但对VC含量没有明显的影响.1-MCP处理对‘亚特,猕猴桃有良好的贮藏保鲜效果.     

不同产地‘南果梨’贮藏中糖酸含量变化研究

作者对鞍山坡地和沈阳坡地、平地栽培的‘南果梨’,测定常温贮藏下果实可滴定酸和可溶性固形物的含量,同时比较常温和4℃下1-MCP处理的果实可滴定酸和可溶性固形物的含量。结果表明,原产地鞍山坡地‘南果梨’果实在常温贮藏下的可滴定酸和可溶性固形物含量高于沈阳坡地的,沈阳坡地的高于平地的;常温1-MCP处理能更好地延缓果实可滴定酸分解和可溶性固形物的积累,使‘南果梨’在采后室温贮藏过程中保持良好的风味品质。     

外源乙烯熏蒸对1-MCP处理猕猴桃货架品质的影响

以1-甲基环丙烯(1-MCP)处理并低温贮藏120 d的‘徐香’猕猴桃为试材,采用200 mg·L^-1外源乙烯分别熏蒸5 h和10 h,测定和分析果实在10 d常温货架(20℃)期间的品质指标变化,以期为猕猴桃商品化处理技术提供参考依据。结果表明:与不经乙烯处理的果实相比,外源乙烯熏蒸提高了1-MCP处理猕猴桃的呼吸速率和乙烯释放速率,保持了较高的可溶性糖含量和果肉色泽a^*值,加快了果肉、果心硬度以及可滴定酸含量的下降,明显提高了果实在货架期的感官品质,其中乙烯熏蒸10 h的效果较好。外源乙烯熏蒸可以促进1-MCP处理猕猴桃在货架期的正常后熟,降低1-MCP对果实食用品质的不利影响。     

1-MCP处理对不同采收成熟度‘徐香’猕猴桃保鲜效果的影响

以‘徐香’猕猴桃为试材,研究了4个采收期(盛花期后1301、381、46和154 d)1-MCP(1-甲基环丙烯)浓度为0.5μL/L处理24 h后,在(2±1)℃下贮藏后的保鲜效果。结果表明:1-MCP能够显著降低‘徐香’果实低温贮藏过程中呼吸速率、乙烯释放速率,延缓果实硬度、可滴定酸的下降以及可溶性固形物的上升;4个采收期的1-MCP处理果实出库后均能正常后熟,但品质和保鲜效果存在差异,其中Ⅱ、Ⅲ期处理果实在贮藏期结束时保持较高的硬度、可滴定酸和VC含量,并且110 d时失重和腐烂率较低;货架期末硬度、糖酸比相对较高,失重率和腐烂率较低。由此推断‘徐香’猕猴桃盛花期后138~146 d采收品质好,此时的1-MCP处理效果最佳。     

1-MCP 对新红星苹果乙烯代谢和贮藏品质的影响

 以新红星苹果为试材, 研究了室温贮藏和低温贮藏两种条件下1-MCP (1 - 甲基环丙烯) 对果实乙烯释放量、内源乙烯浓度、硬度、可滴定酸含量及可溶性固形物含量的影响。结果表明, 300 nL·L ^-1浓度的1-MCP 能显著抑制果实乙烯释放, 延缓乙烯高峰的出现, 延缓果实硬度和可滴定酸含量的下降, 但对可溶性固形物含量无影响。     

1-MCP对不同成熟度粉红女士苹果贮藏生理和品质的影响

以粉红女士苹果为试材,研究了1-MCP对不同成熟度果实贮藏生理的影响。结果表明,用0.5μL/L的1-MCP在20℃下处理粉红女士苹果24h,显著降低果实在0℃贮藏期间呼吸速率、乙烯释放速率和ACC氧化酶活性,延缓果实硬度和可滴定酸含量下降。虽然不同成熟度的果实呼吸高峰和乙烯释放速率到达平台期的时间不同,但1-MCP处理对不同成熟度果实品质的影响无明显差异。SDS-PAGE分析表明粉红女士苹果在贮藏过程中出现了分子质量分别为37.1、18.0、16.6ku的3条特异性蛋白条带,1-MCP处理显著抑制特异蛋白表达,延缓特异蛋白出现的时间。     

Changes in ripening behavior of ‘d'Anjou’ pears (Pyrus communis L.) after cold storage

‘d'Anjou’ pear fruit, harvested at optimum maturity with flesh firmness of 6.8 kg, were stored at ?1.1°C. Fruit were ripened at 20°C for 15 days following storage for 1–8 months. Dessert qualities were evaluated organoleptically on Day 10 of each ripening period. Changes in fruit firmness, extractable juice, titratable acids, solubl solids, respiration, ethylene production and internal ethylene were determined daily during each ripening period. Fruit firmness declined continually from 6.8 kg at harvest to 4.5 kg after 8 months of storage. Fruit stored for 2–8 months softened with a similar pattern during a 15-day ripening period at 20°C, while fruit stored for 1 month softened at a slower rate during ripening to 3.2 kg, with a coarse and dry texture after 15 days at 20°C. Fruit stored for 2–4 months ripened with the desirable buttery and juicy texture, while those stored for more than 5 months ripened with a coarse or mealy and dry texture. The buttery and juicy texture was highly correlated with a lower extractable juice, which could be used for quantitative determination of storage life based on ripened fruit quality. Changes in titratable acids and soluble solids during each ripening period were not associated with changes in dessert qualities of the ripened pears. Rates of respiration, ethylene production and internal ethylene during ripening at 20°C varied with duration of storage, but were not associated with changes in dessert qualities of the ripened fruit.     

Effects of 1-methylcyclopropene (1-MCP) on ripening of apple fruit without cold storage

Summary

The objectives of this study were to determine the efficacy of 1-methylcyclopropene (1-MCP) treatment on ripening of ‘Tsugaru’ fruit at different stages of maturity (early, mid-, and late harvest) and the responses of the early- to late-maturing apple cultivars,‘Tsugaru’,‘Hongro’ and ‘Fuji’, respectively, during storage at ambient temperature (20º ± 2ºC). Fruit at different stages of ripening were treated with 0.5, 1.0, or 2.0 µl l^–1 1-MCP for different durations (e.g., 1.0 µl l^–1 1-MCP for 8 h, 16 h, or 24 h) or with various delays before treatment (e.g., 1.0 µl l^–1 1-MCP on the day of harvest, or 1 d, or 2 d later). Application of 1-MCP to unripe fruit inhibited ethylene production, lowered the rate of respiration and maintained titratable acidity (TA) more effectively than when more mature fruit was treated. However, the effects of 1-MCP on flesh firmness were similar for apples at mid- or late harvests. 1-MCP treatment of early-harvested fruit of the early-maturing ‘Tsugaru’, which had the highest level of ethylene production and respiration rate, inhibited softening and loss of TA to a greater extent than for late harvested fruit. The same pattern of softening was found for ‘Hongro’ and ‘Fuji’. Firmness of ‘Tsugaru’ and ‘Fuji’ apples was maintained after 8 h treatment with 1.0 µl l^–1 1-MCP, while a 16 h treatment was required for ‘Hongro’. Treatment delays of ≤ 2 d before the application of 1-MCP had no negative impact on fruit firmness. Overall, these results indicate that 1-MCP can be used to maintain the quality of non-refrigerated apples.     

1-MCP处理对“东红”猕猴桃货架期品质的影响

以"东红"猕猴桃为试材,通过采后用不同浓度(0、0.25、0.50、0.75μL·L^-1)1-甲基环丙烯(1-methylcyclopropene,1-MCP)进行处理后,将果实至于(20.0±0.5)℃层析冷柜中对其进行货架期贮藏,研究"东红"猕猴桃果实品质的变化,以期为延长猕猴桃货架期品质提供参考依据。结果表明:0.75μL·L^-11-MCP能够有效地抑制"东红"猕猴桃果实硬度、b*值、超氧化物歧化酶(SOD)活性及过氧化氢酶(CAT)活性的下降;0.75μL·L^-1及0.50μL·L^-11-MCP均能够显著降低"东红"猕猴桃果实呼吸强度、乙烯生成速率和脂氧合酶(LOX)活性;0.25、0.50、0.75μL·L^-11-MCP能够更好地推迟"东红"猕猴桃果实可溶性固形物含量的上升,而不同浓度1-MCP处理间对"东红"猕猴桃果实可滴定酸含量的作用效果无显著差异。综合比较,0.75μL·L^-11-MCP能够更好地保持"东红"猕猴桃的货架期品质,其次为0.50μL·L^-11-MCP。综合考虑"东红"猕猴桃货架期品质变化及成本,建议"东红"猕猴桃的1-MCP使用浓度为0.50~0.75μL·L^-1。     

Involvement of 1-methylcyclopropene in ripening of harvested mei (Prunus mume) fruit

Summary

Harvested mei (Prunus mume) fruit were stored at 20°C after exposure to 500 nl l^–1 1-methylcyclopropene (1-MCP) for 8 h. Firmness, peel colour, chlorophyll content, chlorophyllase activity, soluble solids content (SSC), titratable acidity (TA), respiration and ethylene production, and cell wall hydrolysis enzyme activities were monitored to determine the efficacy of 1-MCP treatment in delaying mei fruit ripening compared to untreated control fruit. Results showed that control ‘daqinghe’ mei fruit displayed typical climacteric patterns of respiration and ethylene production. Peak CO₂ production and ethylene production were observed after 6 d. Fruit softening was accompanied by a progressive decrease in colour parameters expressed as hue angle (h°), chlorophyll content, SSC, TA and increases in chlorophyllase, pectin methylesterase (PME) and polygalacturonase (PG) activities. 1-MCP treatment prior to the climacteric increase significantly delayed the onset of the climacteric peaks of CO₂ and ethylene production. These delays were associated with reductions in fruit softening, consistent with delaying the activities of PME and PG. Fruit treated with 1-MCP exhibited less peel colour change from green-to-yellow because of their lower levels of chlorophyllase activity and less chlorophyll breakdown. Moreover, 1-MCP treatment also significantly retarded reductions in SSC and TA compared with control fruit. The shelf-life of mei fruit ripening was increased by 4 d following 1-MCP treatment. Thus, 1-MCP treatment can markedly extend the post-harvest life of ‘daqinghe’ mei fruit.