Effect of 1-methylcyclopropene on tomato flavour components, shelf life and decay as influenced by harvest maturity and storage temperature

BACKGROUND: In Florida, tomatoes are harvested green (GR), which includes mature green (MG) and immature green (IG) fruits, and stored at low temperature (13 °C), resulting in poor flavour. Flavour improvement might be achieved if fruits were harvested with some colour (to eliminate IG fruits) and/or stored at higher temperature with the ripening inhibitor 1‐methylcyclopropene (1‐MCP). RESULTS: ‘Florida 47’ tomatoes were harvested at GR (MG + IG), breaker (BR), turning (TR) and pink (PK) stages, treated (+) or not (?) with 1‐MCP and stored at 13 and/or 18 °C. 1‐MCP treatment resulted in a gain of up to 6 days of shelf life depending on harvest maturity and storage temperature. Storage at 18 °C rather than 13 °C resulted in an increase in internal red colour, soluble solids (SS)/titratable acidity (TA) ratio and levels of many volatiles studied. The shelf life of BR (+) MCP fruits stored at 13 °C was similar to that of MG fruits. IG fruits exhibited lowest levels of SS, TA and ten volatiles compared with BR fruits. CONCLUSION: Harvesting tomatoes with colour (BR), thereby eliminating IG fruits, and treating with 1‐MCP resulted in better quality with adequate shelf life. Published 2011 by John Wiley & Sons, Ltd.     

Combination of 1-methylcyclopropene treatment and controlled atmosphere storage retains overall fruit quality and bioactive compounds in mango

BACKGROUND: Postharvest application of fungicide prochloraz and hot‐water dip are commercially practiced to control postharvest diseases in mangoes. Owing to the increasing consumer demand for organically produced fruit, the search for natural environmentally friendly alternative products and processes has become important for the fruit industry. This study evaluated the combined effect of 1‐methylcyclopropene (1‐MCP) (500 nL L^?1) and controlled atmosphere storage conditions (CA‐1, 5% O₂ + 5% CO₂ or CA‐2, 3% O₂ + 8% CO₂) on the maintenance of fruit quality and bioactive compounds on hot‐water treated mangoes (cv. Kent) during postharvest storage. RESULTS: In comparison to the 1‐MCP + CA‐1 treatment, 1‐MCP + CA‐2 reduced the incidence of anthracnose, weight and firmness loss; delayed the skin and flesh colour development; prevented the increase of soluble solids concentration/titratable acidity ratio, ethanol and acetaldehyde content; and maintained the ascorbic acid, carotenoid, total phenolic and flavonoid contents, and antioxidant scavenging activity in hot‐water treated mangoes. The untrained panel preferred 1‐MCP + CA‐2 treated fruit to the fruit subjected to other postharvest treatments adopted in this investigation. CONCLUSION: Our investigation suggests that the combined effect of 1‐MCP and CA‐2 storage can be recommended as an alternative treatment to replace prochloraz application for hot‐water treated mangoes and can be adopted commercially for organic export markets. Copyright © 2011 Society of Chemical Industry     

不同浓度的1-甲基环丙烯处理对香蕉果实 贮藏品质的影响

以香蕉果实（Cv. ‘Baxi’）为研究材料,研究不同浓度的1-甲mc基环丙烯(1-methylcyclopropene, 1-MCP)处理（0、0.5、1.0和2.0 μL/L）对香蕉果实贮藏品质的影响。 方法 测定了病情指数、果皮色泽、果皮细胞膜透性、果实硬度、可溶性固形物（TSS）含量、可滴定酸（TA）含量以及维生素C（Vc）含量。结果 与对照相比,乙烯利处理加速了果实成熟与品质变化,而1-MCP处理大大抑制了病情指数的提高和果皮色泽的变化,抑制了果皮细胞膜透性的上升和果实硬度的下降,延缓了TSS、TA和Vc含量的变化,几种处理浓度中,0.5 μL/L的1-MCP处理浓度效果最显著。结论 0.5 μL/L的1-MCP处理能够有效抑制香蕉果实的成熟与软化,延长贮藏时间。     

1-甲基环丙烯处理对樱桃番茄果实低温贮藏品质的影响

为了探讨低温贮藏条件下1-甲基环丙烯(1-methylcyclopropene,1-MCP)处理对樱桃番茄果实采后品质的影响,该研究以'粉娇'樱桃番茄为试材,测定了经1-MCP(0.14μL/L)处理的樱桃番茄在低温[(8±1)℃]贮藏期间果实腐烂率、呼吸强度、果实硬度、可溶性固形物、维生素C、有机酸和类胡萝卜素含量的...     

Extending the shelf‐life of bananas with 1‐methylcyclopropene and a chitosan‐based edible coating

BACKGROUND: The marketability of bananas over long distances has been limited due to their highly perishable nature and sensitivity to ethylene. To increase the shelf‐life several alternatives have been tested in attempts to maintain quality characteristics. We evaluated the effects of 1‐methylcyclopropene (SmartFresh^SM, 1‐MCP) and a chitosan‐based edible coating (FreshSeal^®, EC), applied alone or combined, on bananas at ripeness stage 3. All fruits were stored for 8 days at 22 °C, 85% RH. Color development, weight loss, firmness, physiological, sensory and chemical variables were evaluated. RESULTS: After 3 days, control and EC‐treated fruits were completely yellow (°Hue = 90), while 1‐MCP treated fruits alone and combined with EC were still showing some green colorations on tips and neck of fingers. After 7 days, fruits treated with the combination (EC + 1‐MCP) reached a Hue value of 90. Firmer fruits were observed with 1‐MCP alone or combined with EC. A decrease of 0.15% titratable acidity and an increase of 8°Brix were observed in all treatments during the experiment. The incidence of sugar spots was delayed and diminished on fruits treated with 1‐MCP either alone or combined. Sensory results showed no adverse effects by using the 1‐MCP or the edible coating. CONCLUSION: The combined treatment of EC + 1‐MCP could be used to extend the commercial life of bananas for up to four more days. Copyright © 2009 Society of Chemical Industry     

臭氧、1-MCP和乙烯吸收剂组合处理对番茄保鲜效果的影响

研究不同保鲜剂组合处理对番茄保鲜效果的影响。分别进行以下处理:乙烯吸收剂和臭氧组合处理,1-MCP和臭氧组合处理,乙烯吸收剂(EA)和1-MCP及臭氧组合处理,以不进行三者处理为对照。臭氧间隔处理浓度为17.14 mg/m³,时间15 min,用微孔膜包装,每袋7.5 kg,于(10±1) ℃下贮藏。并通过测定番茄硬度、呼吸速率、营养成分、代谢产物、酶活性和香气含量等指标来确定处理番茄的最佳的保鲜剂组合。结果表明:与其它处理相比,采用O₃+EA+1-MCP处理可较好地保持番茄硬度,抑制呼吸,减缓可滴定酸、可溶性固形物、维生素C和番茄红素含量的降低,抑制丙二醛的积累、抗坏血酸过氧化物酶和过氧化物酶的活性,保持番茄的香气含量。O₃+EA+1-MCP处理对番茄具有良好的保鲜效果。     

Expression of genes associated with ethylene-signalling pathway in harvested banana fruit in response to temperature and 1-MCP treatment

BACKGROUND: Little attention has been paid to characterising the ethylene‐signalling pathway genes in relation to abnormal ripening of harvested banana fruit during storage at high temperature. The aim of the present study was to investigate banana fruit abnormal ripening and the expression of ten genes associated with the ethylene‐signalling pathway, namely MaACS1, MaACO1, MaERS1–4 and MaEIL1–4, at high temperature. Changes in these parameters of banana fruit at high temperature in response to 1‐MCP pretreatment were also investigated. RESULTS: High temperature accelerated the decline in fruit firmness, increased ethylene production and inhibited degreening in banana fruit, resulting in fruit abnormal ripening. In addition, the expression of MaACS1, MaACO1, MaERS2, MaERS3, MaERS4, MaEIL1, MaEIL3 and MaEIL4 was enhanced in banana fruit stored at high temperature. However, application of 1‐MCP prior to high temperature storage delayed fruit abnormal ripening and simultaneously suppressed the expression of MaACS1, MaERS2, MaERS3, MaEIL1, MaEIL3 and MaEIL4. CONCLUSION: The findings of this study suggested that the expression of genes associated with the ethylene‐signalling pathway might be involved in banana fruit abnormal ripening at high temperature. Application of 1‐MCP suppressed the expression of genes associated with the ethylene‐signalling pathway, which may be attributed at least partially to 1‐MCP delaying fruit abnormal ripening at high temperature. Copyright © 2010 Society of Chemical Industry     

1-MCP处理对苦瓜果实贮藏品质和采后生理的影响

研究了1-甲基环丙烯（1-MCP）处理对苦瓜果实贮藏品质和采后生理的影响。苦瓜果实采后用0.5、1.0、1.5μL/L1-MCP处理12 h后,在20℃下贮藏。贮藏期间测定果实腐烂率、硬度、色差、可溶性固形物和可滴定酸含量、抗坏血酸含量、H2O2含量、超氧阴离子产生速率、果实的过氧化氢酶及过氧化物酶活性等指标的变化。结果表明:与对照组果实相比,1-MCP处理能有效延缓苦瓜果实硬度的下降,保持较高的抗坏血酸、可滴定酸和可溶性固形物含量,抑制果实中H2O2、O2-·含量的上升;且在整个贮藏期间,能够有效增加处理组果实过氧化物酶和过氧化氢酶的活性。另外,1-MCP还可以抑制果实的腐烂,但是过高浓度反而会增加果实的腐烂。研究认为,0.5μL/L 1-MCP处理可延缓采后苦瓜果实成熟衰老和贮藏品质下降,在20℃下延长贮藏时间达4 d以上。      

不同品种番茄对发酵番茄酱品质的影响

为了丰富番茄加工品种,开发一种发酵番茄酱。以四种新鲜的番茄品种为原料,添加凯里红酸汤来制作发酵型番茄酱并跟踪发酵过程中总酸、pH值、亚硝酸盐、番茄红素、可溶性固形物含量变化以及对成品感官评价。结果显示：美宝、奥宝番茄感官评价较好,品种间pH值变化无显著差异（P＞0.05）,美宝总酸含量、亚硝峰峰值最高,发酵结束后美宝总酸比市售番茄酱高出34%。美宝、经典欧卡番茄其与市售番茄酱番茄红素含量相近。美宝可溶性固形物含量最高为42%,各品种可溶性固形物含量均大于市售番茄酱。不同品种番茄酱发酵后成分具有一定的差异,结合不同品种的发酵番茄酱之间的特点,美宝番茄发酵后风味比市售番茄酱更佳。     

Effects of ripening, 1-methylcyclopropene and ultra-high-pressure pasteurisation on the change of volatiles in Chinese pear cultivars

BACKGROUND: Aroma is one important fruit sensory attribute influenced by the volatile constituents related to species, variety and technological treatments. We analysed the variations of volatile compounds in five pear cultivars and investigated their changes related to different pear organs, different ripening stages, 1‐MCP treatment and ultra‐high‐pressure pasteurisation. RESULTS: Considerable variations exist in the quantity of 10 volatile compounds among five pear cultivars. Their levels generally showed an increasing trend when collected at later harvest time in Ya pear. In Whangkeumbae pear, most volatile compounds reached their maximum levels in skin and pulp. After treating pears with 42 µmol L^?1 1‐methylcyclopropene (1‐MCP), the levels of volatiles remained basically unchanged or only slightly increased in Ya pear during a shelf life of 21 days. When Huangguan pear juice was pasteurised by using ultra‐high pressure, the levels of volatiles significantly changed during the shelf life. CONCLUSION: The volatile compositions of five different Chinese pear cultivars differ considerably. The levels of these volatiles vary along with ripening stages and pear tissues. A moderate concentration of 1‐MCP could keep the levels of volatile compounds basically unchanged during storage and ultra‐high‐pressure pasteurisation could change the levels of volatiles significantly during the following shelf life. Copyright © 2011 Society of Chemical Industry     

一氧化氮对绿熟和粉红期番茄采后抗氧化相关酶的影响

以\     

烹饪方式对芹菜和番茄品质的影响

以炒、炖、焖三种方法处理芹菜和番茄,比较烹饪后芹菜和番茄感官、营养品质的变化,研究不同烹饪方式对芹菜和番茄品质的影响,便于快速对膳食进行营养评价和营养配餐。结果表明,烹饪后芹菜和番茄中可溶性糖、可溶性蛋白质、维生素C含量都有明显降低,番茄中膳食纤维则有显著增加,两者表面的颜色加深,亮度减小,黄褐色加深。相对于炖和焖,炒对芹菜总色差、可溶性糖、可溶性蛋白质、膳食纤维含量的破坏性较小;炒后番茄总色差损失量较大;焖对两者中的维生素C有一定保护作用。不同蔬菜经不同烹饪处理后各项品质指标变化不同,宜建立相应的品质指标变化特征库,以便于快速对膳食进行营养评价和配餐。      

1-MCP suppresses ethylene biosynthesis and delays softening of 'Hami' melon during storage at ambient temperature

BACKGROUND: ‘Hami’ melon is susceptible to softening during postharvest storage at ambient temperature, which enhances postharvest deterioration and limits transportation and storage. To look for a method of softening control, the effect of 1‐methylcyclopropene (1‐MCP) on regulating postharvest softening of ‘Hami’ melon fruit was investigated. RESULTS: 1‐MCP treatment at 1 µL L^?1 significantly reduced ethylene production and maintained higher levels of fruit firmness. It also markedly inhibited the accumulation of 1‐aminocyclopropane‐1‐carboxylic acid (ACC) and maintained lower activities of ACC synthase and ACC oxidase. In addition, 1‐MCP treatment reduced the activities of fruit‐softening enzymes such as pectin methyl esterase, polygalacturonase, endo‐1,4‐β‐glucanase and β‐galactosidase. CONCLUSION: 1‐MCP was effective in suppressing ethylene production and delaying fruit softening in ‘Hami’ melon by decreasing the activities of ethylene biosynthesis enzymes and inhibiting fruit‐softening enzymes. Copyright © 2011 Society of Chemical Industry     

Chemical composition and in-vitro degradability of major chemical constituents of red clover harvested at different stages of maturity

The contents of extractives, starch, crude protein, non-starch polysaccharides and Klason lignin were determined in red clover harvested at six different stages of maturity. Chemical analysis of residues after incubation with rumen liquor in vitro revealed that the degradability of starch was 100% and of crude protein about 80% at all harvest times. The degradability of non-starch polysaccharides decreased from 76 to 51% during maturation and no degradation of Klason lignin was noticed. At all harvest times xylose was the least degraded non-starch polysaccharide residue followed by glucose and rhamnose. During maturation the greatest decrease in in-vitro degradability was noticed for the xylose residues followed by the glucose and the mannose residues.     

不同成熟度柑橘力学特性研究

为避免机器人在采摘柑橘过程中对柑橘造成破坏,利用TA-XT2i型质地分析仪对青色柑橘、半成熟柑橘和成熟柑橘整果进行纵向压缩和横向最大截面处穿刺实验,研究不同成熟度柑橘的压缩抗力和最大抗穿刺力,结果表明,青色柑橘的抗破坏能力最强,承受的最大压力不宜超过190N,最大穿刺力不宜超过8N;成熟柑橘的抗破坏能力最差,承受的最大压力不宜超过100N,最大穿刺力不宜超过3N;半成熟期柑橘承受的最大压力不宜超过120N,最大穿刺力不宜超过5N。