1- 甲基环丙烯复合焦亚硫酸钠处理对厚皮甜瓜的保鲜效果

以陕西省阎良区厚皮甜瓜为试材,采用1-甲基环丙烯(1-MCP)、焦亚硫酸钠(Na2S2O5)以及二者结合的处理方法,研究厚皮甜瓜采后生理变化及贮藏品质。结果表明：1-MCP结合Na2S2O5处理能明显延缓厚皮甜瓜硬度下降,抑制可溶性固形物含量快速上升,有效少果实腐烂,同时抑制苯丙氨酸解氨酶和过氧化物酶的活性,使过氧化氢酶和超氧化物岐化酶活性处于较高水平。在这种处理方式下,贮藏80d后,果实腐烂指数0.37、商品果率80%。1-MCP结合Na2S2O5复合处理对厚皮甜瓜具有很好的保鲜效果。     

哈茨木霉菌剂处理提高网纹甜瓜(Cucumis melo L. var. reticulatus Naud.)的货架期品质

该研究探讨了哈茨木霉菌剂处理对网纹甜瓜货架期品质的影响。研究在网纹甜瓜种植过程中,对甜瓜根部施用哈茨木霉菌剂4次（每次剂量为0.1 g/m2）,以根部施用清水为对照组,比较果实在10 ℃冷库中贮藏第0、5、10和15 d的感官得分、颜色、质构、口味和抗氧化能力等品质特征。结果表明：哈茨木霉处理后果肉的口感甜糯,质地均一,果实最佳赏味期较对照组延长约4 d;哈茨木霉处理组果实可溶性固形物含量和Vc含量分别比对照组提高15.20%和64.58%;哈茨木霉组的ORAC值达到667.80 (µmol/L)/100 g,比对照组提高了10.05%,果实的抗氧化能力显著性提高;并且哈茨木霉处理使果皮硬度提高1.75倍,延缓果肉的软化现象,使果实更加便适于贮藏和运输。因此,种植过程中在根部追施哈茨木霉菌剂有利于提高网纹甜瓜货架期品质。     

1-MCP对采后果实贮藏品质影响的研究进展

1-甲基环丙烯(1-MCP)为一种新型乙烯受体抑制剂,具有延缓果实衰老作用。它通过与乙烯受体蛋白的不可逆的竞争结合,干扰乙烯与其受体上的金属离子正常结合而在激素水平上影响果实对乙烯的响应。本文就1-MCP处理分别对呼吸跃变型和非呼吸跃变型果实采后生理及品质的效应以及对贮藏病害的影响进行了综述,旨为1-MCP绿色安全果实保鲜剂的应用推广提供技术思路。1-MCP对果实保鲜具有双向调节作用,1-MCP对采后果实的贮藏品质影响与其使用浓度、处理时间、处理方法及不同种类果实、呼吸漂移类型、采收期、贮藏温度等多种因素密切相关。     

高压二氧化碳处理对鲜切哈密瓜微生物与品质的影响

本实验以哈密瓜为原料,优化了清洗工艺,研究了高压二氧化碳（high pressure carbon dioxide,HPCD） 处理对鲜切哈密瓜贮藏期间（4 ℃避光贮藏8 d）微生物（菌落总数、霉菌和酵母菌总数）、感官指标（质量损失 率、质构、感官评价）、品质指标（可溶性固形物含量、pH值、VC含量）、酶（多酚氧化酶（polyphenoloxidase, PPO）、过氧化物酶）活力的影响。本研究首先确定了强酸电解水清洗25 min为最佳清洗工艺,清洗后鲜切哈密 瓜的菌落总数下降了0.81（lg（CFU/g））。2.5、3.5、4.5 MPa处理8 min后的鲜切哈密瓜在贮藏期间微生物数量显 著增加,PPO活力上升,且在贮藏8 d时,质量、硬度和VC含量分别下降了16.45%～42.70%、30.38%～48.97%和 96.25%～96.73%。本研究为HPCD技术应用于鲜切哈密瓜加工提供了理论依据。     

1-甲基环丙烯和壳聚糖对鲜切西兰花活性氧代谢及保鲜效果的影响

研究1-甲基环丙烯(1-MCP)、壳聚糖对鲜切西兰花贮藏期间活性氧代谢及保鲜效果的影响。实验设置1-MCP(2μL/L)、壳聚糖(2%)及1-MCP联合壳聚糖3个处理,以未加处理的鲜切西兰花为对照,对鲜切西兰花10℃贮藏期间的相关指标进行测定。结果表明:1-MCP处理能显著降低呼吸作用,维持较高的超氧化物歧化酶(SOD)、过氧化物酶(POD)活性,减少了O-2.和H2O2及MDA在体内的积累,延缓VC和叶绿素含量的下降,表现出很好的贮藏效果;壳聚糖处理与1-MCP处理效果相反,缩短了鲜切西兰花的贮藏时期;与对照相比,1-MCP联合壳聚糖虽有一定保鲜效果,但两者差异不明显。     

Cultivar and Maturity Effects on Muskmelon ( Cucumis melo) Colour,Texture and Cell Wall Polysaccharide Composition

Cell wall polysaccharides (CWP) of two types of melons were isolated and purified. Fractionations were performed using cyclohexanetrans-1,2-diamine tetraacetate (CDTA), Na₂CO₃, guanidinium thiocyanate (GTC) and KOH. Alditol acetate derivatives of neutral sugars from each CWP fraction were prepared and analysed by gas chromatography. Trifluoro-acetic acid insoluble fractions were analysed colorimetrically and uronic acid was determined. The CDTA and Na₂CO₃ fractions were found to be composed of typical pectic materialscontaining primarily galacturonic acid with the neutral sugars arabinose, galactose, rhamnose and a smaller amount of xylose. As maturity increased, CDTA fraction yields increased, though total neutral sugar CWP compositions decreased. GTC and KOH fractions were typical of hemicellulose, and contained principally xylose, glucose, galactose, mannose and fucose, with very small amounts of uronic acid, arabinose and rhamnose. The residues contained principally glucose and galactose, with smaller amounts of mannose, xylose, arabinose and fucose. With the exception of xylose and glucose, all neutral sugars decreased significantly during ripening in both the Cantaloupe and Honey Dew melons. Total uronic acid did not change as maturity increased, except for Cantaloupe, where total uronic acid decreased from the ripe to overripe stages. Relationships between firmness, drip loss and other composition measurements, as well as the total CWP sugar composition, were also determined. Only the CDTA fraction yields were negatively correlated with the changes in firmness of both melons and positively correlated with changes in drip loss as maturity increased.     

Relationships between volatile composition and sensory evaluation in eight varieties of netted muskmelon (Cucumis melo L var reticulatus Naud)

The quality parameter of muskmelon (Cucumis melo L var reticulatus Naud) is often identified with the sugar content, particularly sucrose. However, high soluble solids concentration at harvest does not always correspond with high overall fruit quality and should be used in conjunction with the evaluation of aroma. In order to find quality indices, correlations were checked between aroma compounds detected on the melon pulp by headspace gas chromatography and sensory evaluation. Eight cultivars of muskmelon were analysed for their aroma content and other quality parameters. Aroma compounds were mainly esters, while (Z)‐6‐nonenal and (E)‐6‐nonenol, characteristic of melon, were not detected with the technique used. The data were subjected to statistical analyses in order to find significant correlations. High values of correlation were not found between chromatographic and sensory data, but a high correlation was found between total aromas and ethyl esters, both data of analytical source. This fact means that ethyl esters could be very important compounds for melon flavour and could be considered as markers of a good‐quality aroma. © 2002 Society of Chemical Industry     

Influence of 1-Methylcyclopropene (1-MCP) on Postharvest Storage Quality in Green Bell Pepper Fruit

The goal of this research was to evaluate the efficiency of 1-methylcyclopropene (1-MCP) on maintaining the quality parameters and antioxidant activity of bell pepper cv. Selika (an original red cultivar) and cv. H1530 (??ever-green?? line) after 18?days storage at 7°C and 3?days at 20°C. Fruits were harvested at green color, from a commercial shade net house in the desert region in Israel. In both cultivars, 600?nL?L^?1 1-MCP reduced weight loss and maintained firmness more than control or 900?nL?L^?1 1-MCP. Overall, 1-MCP treatment had a pronounced effect on delaying ripening processes as shown by inhibiting color changes, decreasing decay, and maintaining quality of non-climacteric green pepper fruit. 1-MCP treatment reduced the lipophilic antioxidant activity of this fruit, but the hydrophilic antioxidant activity remained similar to that observed at harvest.     

Modified Atmosphere Maintains Quality of Fresh-cut Cantaloupe (Cucumis melo L.)

ABSTRACT: Fresh-cut cantaloupe cubes were placed in film-sealed containers in which the internal gas mixture was attained naturally (nMAP), was flushed with 4 kPa O₂ plus 10 kPa CO₂ (fMAP), or was maintained near atmospheric levels by perforating the film (PFP). While both nMAP and fMAP maintained the salable quality of melon cubes for 9 d at 5°C, fMAP maintained quality better than nMAP. The benefit of fMAP was indicated by better color retention, and by reduced translucency, respiration rate, and microbial population compared with nMAP. Shelf life of cubes in PFP was only 5 to 7 d at 5°C, and its rapid decline was due to tissue translucency and/or off-odor development.     

运输振动对鲜切生菜品质的影响

研究运输振动强度对鲜切生菜品质的影响。采用箱式冷藏车装载鲜切生菜,模拟商业化送货,然后在超市货架4 ℃贮藏,测定其在货架期第0、2、4、6天品质变化情况。结果发现,箱式冷藏车在行驶过程中垂直方向加速度最大,车厢内不同部位振动强度不同,其中车厢后上部分振动强度最大。在货架期第4天,车厢后上部位鲜切生菜粉变率最高,膜脂损伤严重。运输振动引起鲜切生菜品质下降,振动强度越高,鲜切生菜品质越差。因此,车厢后上部位会引起鲜切生菜品质的明显下降。     

1-甲基环丙烯对蓝靛果贮藏品质的影响

目的:探究1-甲基环丙烯(1-Methylcyclopropene,1-MCP)对蓝靛果贮藏品质的影响,以期为蓝靛果鲜果贮藏保鲜技术提供理论和实践依据.方法:以蓝精灵蓝靛果为试材,采后进行浓度为1μL/L 1-MCP处理24 h后,研究冰温(-0.5±0.3)℃贮藏期间1-MCP处理对果实贮藏品质、生理变化和抗氧化...     

Repetitive pulsed light treatment at certain interval on fresh-cut cantaloupe (Cucumis melo L. reticulatus cv. Glamour)

This study was done in order to investigate the effect of repetitive pulsed light (RPL) treatment at certain interval on microbiological stability, quality and physicochemical changes of fresh-cut cantaloupes during storage. Fresh-cut cantaloupes packed in polypropylene bag were exposed to RPL treatment with fluences of 0.3, 0.6, 0.9 and 1.2 J/cm² every 48 h up to 28 days of storage at 4 ± 1 °C. The microbiological quality, headspace gas composition, physical quality (firmness, fluid loss and colour), chemical quality (pH, titratable acidity, total soluble solids, total phenolic content and ascorbic acid content) and microscopic observations of fresh-cut cantaloupes were determined during storage. No significant (p > 0.05) effect was observed for firmness, colour and total soluble solids of fresh-cut cantaloupes treated with RPL throughout the storage study. Repetitive PL treatment using 0.9 J/cm² was the most effective fluence for extending the shelf life of fresh-cut cantaloupes with extension by 20 days compared to control in term of microbiological quality while maintaining all quality parameters. Negative effect of single PL treatment (SPL) (11.7 J/cm²) on tissue structure of fresh-cut cantaloupes during storage was minimised by applying RPL treatment (0.9 J/cm² for every 48 h interval).Industrial relevanceFresh-cut cantaloupes are becoming more popular due to the benefits of convenience and fresh-like quality provided. However, fresh-cut cantaloupes are susceptible to microbial contamination and deterioration as the fruit tissue is injured due to cutting of the product into pieces. Repetitive PL (RPL) treatment is an alternative application to single PL (SPL) treatment for extending shelf life of fresh-cut fruits by minimising the negative effect of SPL treatment on the tissue structure. This study demonstrates the usefulness of RPL treatment to further extend the shelf life of fresh-cut cantaloupes compared to SPL treatment. This is crucial for vending cut fruits through refrigerators equipped with RPL system. The RPL application contributes to reduced postharvest loss and increased convenience and availability of fresh-cut fruits to the public which benefit both producers and consumers.     

1-甲基环丙烯和二氧化氯复合处理对冬枣采后生理及贮藏品质的影响

为探讨冬枣绿色保鲜新技术,研究1-甲基环丙烯(1-methylcyclopropene,1-MCP)与二氧化氯(chlorine dioxide,ClO2)单独及复合处理[3μL/L 1-MCP与100μL/L ClO2熏蒸、4℃条件下贮藏]对冬枣采后生理和贮藏特性的影响,贮藏过程中每10 d测定转色、腐烂、硬度、含水量、可溶性固形物(total soluble solids,TSS)、可滴定酸(titratable acid,TA)、维生素C(vitamin C,VC)、总酚、还原力和DPPH自由基清除率的情况。研究结果表明:1-MCP或ClO2单独处理都能有效延缓果实转色,减少果实腐烂,保持果实较高的含水量、硬度、TSS含量、TA含量、VC含量、总酚含量、还原力和DPPH自由基清除率,提高采后冬枣果实的贮藏品质。与单独1-MCP及ClO2处理相比,1-MCP复合ClO2处理的保鲜效果更佳,可作为采后冬枣保鲜的有效手段。     

1-MCP处理对冷藏番荔枝果实贮藏品质和生理变化的影响

以“非洲骄傲”番荔枝果实为试材,研究了1-MCP(1-甲基环丙烯)处理对冷藏(15℃)番荔枝果实贮藏效果和生理变化的影响。结果表明:1.8μl/L1-MCP处理能显著提高番荔枝的好果率,延缓番荔枝贮藏前期TSS含量的上升,推迟其成熟软化进程;1-MCP处理还能显著抑制番荔枝果实VC含量的下降(p<0.01),提高果实贮藏后期SOD、POD和CAT的活性;同时,1-MCP处理抑制了果实中PPO活性的升高和MDA含量的积累。     

不同浓度臭氧对河套蜜瓜贮藏品质影响的研究

研究了10℃贮藏环境中分别以0、50、100、150μl/L臭氧处理对河套蜜瓜可溶性糖、可滴定酸、VC含量以及硬度、失重率、腐烂指数等几个指标的影响。结果表明,适当的臭氧浓度处理可以有效地保持河套蜜瓜贮藏期间的品质,延长贮藏期。在不同浓度的臭氧处理实验中,贮藏环境中的臭氧浓度为50μl/L对保持河套蜜瓜的品质效果最佳。实验还发现较低浓度的臭氧处理对品质的影响相对高浓度处理效果较好。     

Characterisation of wines and distilled spirits from melon (Cucumis melo L.)

Melon fermentation and distillation was studied with a view to produce melon spirits. Three different substrates were obtained from melon (Cucumis melo L.). Sugar concentration was around 60–70 g L^?1 and the pH between 4.6 and 5.2. The substrates were clarified and then fermented at one of two pH levels at 20 °C. A commercial Saccharomyces cerevisiae starter culture was used to obtain melon wines with an alcohol concentration of 3.8–5.8% (v/v). The melon wines were distilled in a distillation column to yield distillates with an alcohol content of 33–60% (v/v). The major volatiles in the melon wines and in the distillates were analysed by gas chromatography (GC). The results demonstrated that melon could be a good substrate of fermentation and distillation but also yielded significant differences in the volatiles analysed in the different melon wines and distillates obtained from the different substrates in the different conditions of the experiment. Fermentation pH greatly affected the methanol, acetaldehyde, and butanol contents and thus the final quality of the spirits produced.     

1-甲基环丙烯保鲜纸研制及应用

选用3种合成方法制备1-MCP包结物,采用气相色谱、红外和核磁共振化学方法对合成产物进表征,设计制备出新型1-MCP保鲜纸并应用于香蕉和番茄的贮藏保鲜。分析1-MCP保鲜纸对香蕉、番茄果实呼吸速率和乙烯释放速率的影响以及及对番茄色泽和可滴定酸含量的影响。结果表明：1-MCP保鲜纸处理对延缓香蕉和番茄的成熟衰老有明显效果,可显著降低香蕉和番茄的呼吸速率和乙烯释放速率,延缓番茄果皮转红,抑制番茄果实中可测定酸含量的下降,该种1-MCP保鲜纸是一种新型的保鲜产品。