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1-MCP结合冰温贮藏对葡萄采后品质及相关生理代谢的调控 总被引:7,自引:0,他引:7
以“乍娜”葡萄为试材,研究0.5μL/L和1.5μL/L 2个用量的1-MCP处理结合冰温贮藏(温度-0.3℃±0.3℃)对葡萄采后主要品质及相关生理指标的作用效果。结果表明:冰温贮藏结合2个浓度的1-MCP处理均可在不同程度上提高葡萄贮藏好果率并降低质量损失率和果梗褐变指数,抑制葡萄果穗呼吸强度和乙烯生成速率的增加,并能够有效抑制果实丙二醛(malondialdehyde,MDA)、超氧阴离子自由基(O2- ·)、过氧化氢(H2O2)含量和脂氧合酶(lipoxygenase,LOX)活性的增加,保持或增大超氧化物歧化酶(superoxide dismutase,SOD)和过氧化物酶(peroxidase,POD)的活性;1μL/L 1-MCP处理结合冰温贮藏作用效果较好,使葡萄贮期较普通冷库对照延长20d。综上所述,适宜浓度的1-MCP处理结合冰温贮藏有利于提高葡萄采后贮藏品质和果实抗性、延缓果实衰老,在鲜食葡萄无硫保鲜方面具有非常好的应用前景。 相似文献
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果蔬细胞壁酶活性与果实的种类和贮藏品质密切相关。本实验以巨峰葡萄为原料,研究不同冷藏温度(0℃和4℃)下与葡萄浆果软化相关的多种酶类:果胶酯酶(PE)、葡聚糖内切酶(EGase)、果胶内切酶(endo-PG)和果胶外切酶(exo-PG)活性的变化规律。结果表明,冰温可以较好地抑制细胞壁酶活性,延长贮藏期。较低的贮藏温度对PE的影响不大,0℃贮藏延缓了EGase活性峰值出现的时间,有效的降低了endo-PG和exo-PG活性。总体来看,EGase、endo-PG和exo-PG活性的变化对葡萄贮藏过程中质地变化及腐烂起到了更为重要的作用。 相似文献
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研究冰温及不同温度处理对湖景蜜露桃贮藏品质的影响,为冰温保鲜技术在南方软质型水蜜桃贮运保鲜上的应用提供依据。以宁波奉化湖景蜜露桃为试材,以冰点测定为主要依据,确定-0.8℃为其适宜的冰温贮藏温度;系统地比较了冰温和3~4,(0±0.5)℃3种温度处理对不同贮期及货架期桃果理化指标(可溶固形物含量、可滴定酸含量、VC、组织电导率)、感官指标(褐变率、果肉明度L*、及感官评分)的影响;采用因子分析法,提取累计贡献率为91.703%的两个因子成分综合评价各处理对水蜜桃贮藏效果。试验结果表明,保鲜效果依次为:冰温(0±0.5)℃3~4℃,冰温可以显著推迟南方软质型水蜜桃冷害的发生,保持桃果品质,保鲜期可延长至40d。 相似文献
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不同保鲜剂结合冰温对玫瑰香葡萄贮藏品质和生理生化的影响 总被引:2,自引:0,他引:2
以玫瑰香葡萄为试材,研究了不同保鲜剂结合冰温(-0.5~-0.2℃)对玫瑰香葡萄采后贮藏品质及生理的影响.结果显示:保鲜剂结合冰温能有效减少葡萄贮藏期间的失重、脱粒、腐烂,延迟可溶性固形物、可滴定酸、Vc含量的下降,较好保持葡萄的外观和风味;并能使葡萄果肉的硬度、弹性、凝聚性、咀嚼性维持在较高的水平;另外,能很好的抑制丙二醛的积累、PPO活性,保持较高的POD、SOD活性,延缓衰老,增长贮藏时间.其中以处理Ⅲ即8g CT2保鲜剂+lgCT5保鲜剂处理对玫瑰香葡萄保鲜效果最好. 相似文献
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冰温结合CT-2保鲜剂对玫瑰香葡萄贮藏品质及生理的影响 总被引:1,自引:1,他引:0
以玫瑰香葡萄为试材,通过对不同处理方式的果实在贮藏期间品质和生理生化指标的变化规律分析,探讨冰温贮藏结合CT-2保鲜剂处理对果实的保鲜效果。结果表明:冰温贮藏结合CT-2保鲜剂处理减轻了葡萄贮藏过程中的失重率、落粒率和腐烂率,降低了葡萄在贮藏过程中可溶性固形物、可滴定酸、Vc含量的损失,较好地保持了葡萄的品质;减缓了丙二醛含量的增长速度,有效延缓了葡萄在贮藏过程中的衰老进程;POD、SOD活性较单纯冰温贮藏有所增加,减少自由基的积累,从而延长了贮藏时间。 相似文献
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《食品与发酵工业》2019,(16):201-207
为探寻鸡肉合适保鲜方法,以4℃对照,研究20 d内,-1.5℃冰温贮藏对鸡肉品质及微观结构影响。结果表明,在4℃与-1.5℃贮藏条件下,随贮藏时间延长,鸡肉L~*、a~*、b~*值均先升高后下降,持水性、硬度、弹性总体下降,TBA值、TVB-N值总体上升,但-1.5℃贮藏鸡肉各项品质指标均明显优于4℃贮藏鸡肉。2种贮藏条件下鸡肉的T_(2b)、T_(21)、T_(22)出峰值均向较长时间方向移动,P_(21)持续下降,P_(22)持续上升;4℃贮藏6 d、-1.5℃贮藏18 d时鸡肉细胞结缔组织开始降解劣化。4℃贮藏4 d与-1.5℃贮藏16 d时,菌落总数分别为7×10~4、3.8×10~5CFU/g(符合国家标准规定限值1×10~6CFU/g),TVB-N值分别为16.55、20.32 mg/100 g(符合国家二级鲜肉标准),冰温贮藏可使鸡肉保鲜期延长12 d。实验结果可为提高鸡肉品质,延长其货架期提供科学依据。 相似文献
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Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides. 相似文献
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John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium. 相似文献
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Yoko Uematsu Keiko Hirata Kumi Suzuki Kenji Iida Kazuo Saito 《Food Additives & Contaminants》2001,18(2):177-185
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties. 相似文献
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A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials. 相似文献
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Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates 总被引:2,自引:0,他引:2
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel. 相似文献
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Dupuis L Manfait M Serpier H Capon F Kalis B 《International journal of cosmetic science》1997,19(1):37-44
This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration. 相似文献
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Anne Theobald Catherine Simoneau Philippe Hannaert Patrizia Roncari Anna Roncari Thomas Rudolph Elke Anklam 《Food Additives & Contaminants》2000,17(10):881-887
The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study. 相似文献