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1.
以‘湘研15号’辣椒为试材,分离、鉴定出4 株辣椒采后病原菌,采用生长速率法测定丁香、肉桂、花椒等9 种植物提取液对尖孢镰刀菌、黑色炭疽菌、红色炭疽菌、根霉菌的抑制效果,通过平板梯度稀释法测定植物提取液对上述4 种供试病菌的最小抑菌浓度(minimum inhibitory concentration,MIC)和最小杀菌浓度(minimum bactericidal concentration,MBC);通过测定辣椒的病斑直径、发病率、总酚及类黄酮含量、苯丙氨酸解氨酶(phenylalanine ammonia lyase,PAL)、过氧化物酶(peroxldase,POD)、多酚氧化酶(polyphenol oxidase,PPO)活力,研究复合涂膜剂诱导辣椒对根霉病的抗性作用。结果显示,丁香、肉桂提取液对4 种供试病原菌的抑菌率均为100%,对尖孢镰刀菌、黑色炭疽菌、红色炭疽菌和根霉菌的MIC均分别为1.25、2.50、2.50 mg/mL和5.00 mg/mL,MBC均分别为2.50、5.00、5.00 mg/mL和10.00 mg/mL。丁香、肉桂提取液复合涂膜剂能有效抑制辣椒的发病率和减小病斑直径,接种第8天时,与刺伤后接种根霉菌孢子组(CK2)相比,复合涂膜剂组发病率降低了6.67%(P>0.05)、病斑直径减小了30.35%(P<0.05);与刺伤后加无菌水组(CK1)和CK2组相比,复合涂膜剂处理辣椒的PAL活力分别提高了45.91%、24.54%(P<0.05);POD活力分别提高了22.15%(P<0.05)、12.54%(P>0.05);PPO活力分别提高了80.00%、28.57%(P<0.05);总酚含量分别提高了60.00%、43.74%(P<0.05);类黄酮含量分别提高了82.05%、61.36%(P<0.05)。结论:丁香、肉桂提取液复合涂膜剂能诱导辣椒对根霉病产生抗性,本研究可为开发高效、稳定、无毒无害辣椒防腐保鲜剂提供理论和技术支持。  相似文献   

2.
食品保鲜剂协同丁香提取液预处理黄花菜的保鲜效果   总被引:1,自引:1,他引:0  
为探索食品保鲜剂协同丁香提取液预处理黄花菜的保鲜效果,分别以丁香提取液和食品保鲜剂协同丁香提取液浸泡黄花菜1min,PVC塑料袋包装于室温下贮藏,贮藏期间测定黄花菜的开花率、腐烂率、失重率和褐变率。结果表明,单纯的丁香提取液对黄花菜的保鲜效果不显著,食品保鲜剂协同丁香提取液预处理黄花菜的保鲜效果显著,保鲜期达到6天,避免了阴雨天气不能及时日光干燥造成的损失。  相似文献   

3.
中草药提取液对巨峰葡萄保鲜效果的研究   总被引:3,自引:0,他引:3  
以黄连、大黄、丁香、甘草、肉桂的提取液为涂膜剂分别对巨峰葡萄进行涂膜,研究其对葡萄贮藏品质的影响。结果表明,五种中草药提取液涂膜处理葡萄后,均可延缓葡萄果实的衰老和品质的劣变。可减少葡萄果实的失重率、腐烂率,可减缓可溶性固形物含量、可滴定酸含量、还原糖含量的下降速度。其中,丁香提取液对葡萄的保鲜效果最好,其次为黄连。  相似文献   

4.
用八角等提取液的抑菌作用和壳聚糖的成膜性研制纯天然、无毒的草莓保鲜剂。制备八角、丁香、肉桂的乙醇提取物,并加入壳聚糖配制不同浓度的保鲜液,将采摘的草莓用保鲜液浸泡5min后捞出,每隔24h测定草莓的失重率、腐烂指数、感官品质、呼吸强度、有机酸含量、可溶性糖含量、VC含量。八角等提取液浓度为2.0%、壳聚糖浓度为1.5%的保鲜液对草莓保鲜效果较好。八角等提取液与壳聚糖复合物对草莓具有明显的保鲜效果。  相似文献   

5.
在前期获得的丁香、五味子抑制蓝莓病原微生物的体外抑菌效果基础上,研究丁香、五味子及壳聚糖复合保鲜剂对"粉蓝"蓝莓的贮藏品质及抗病相关酶活影响。采后蓝莓在质量分数(m/m)分别为0.5%和1.0%的复合保鲜剂中浸泡5 min,晾干后(4±0.5)℃贮藏,每7 d测定果实的失重率、腐烂率、硬度、相对电导率(REC)、丙二醛(MDA)含量、总黄酮(TFC)、总酚(TPC)、二苯代苦味肼基自由基(DPPH·)清除能力、苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)和过氧化氢酶(CAT)活性变化。以无菌水相同处理为对照。结果显示:与对照相比,采用复合保鲜剂进行保鲜处理并结合4℃冷藏,可抑制蓝莓果实贮藏期间的失重率和腐烂率;抑制果实硬度的下降;延缓DPPH·清除能力下降;延缓细胞膜透性增加及丙二醛含量的上升;提高了总酚、总黄酮含量等抗氧化、抗菌物质的含量;在一定程度上提高蓝莓果实中参与苯丙烷代谢的PAL、PPO、POD活性及CAT活性,并在贮藏过程中维持较高的活性,减轻了自由基对果肉组织的侵害,延缓衰老进程。处理2(1.0%复合保鲜剂)对蓝莓的贮藏保鲜效果较好,该复合保鲜剂用于蓝莓保鲜具有操作简单、安全无毒、效果显著的特点,有较好的应用前景。  相似文献   

6.
采用菌丝生长速率法筛选出对草莓采后主要病原菌抑制效果最佳的中草药复合物,并将其与涂膜剂壳聚糖、助剂抗坏血酸(VC)、抗氧化剂植酸复配成复合保鲜剂,通过正交实验确定了各组分的最佳浓度配比:复合中草药提取物0.3%(丁香、蛇床子、补骨脂的质量比为1:1:1)、壳聚糖1.25%、VC1.25%、植酸0.05%。草莓经此复合保鲜液处理后,显著降低了常温贮藏期间的失重率、腐烂率,延缓了可溶性固形物、VC和可滴定酸含量的下降,且各项保鲜指标均优于1.25%壳聚糖的单独涂膜处理。  相似文献   

7.
金瓜复合涂膜保鲜研究   总被引:1,自引:0,他引:1  
研究了不同涂膜处理对金瓜的常温贮藏保鲜效果,结果表明由海藻酸钠0.5%+蔗糖酯0.5%+苯甲酸钠0.5%组成的复合涂膜剂对金瓜的防腐保鲜效果最好,贮藏3个月后无一腐烂,但失重率最高.  相似文献   

8.
为提高壳聚糖季铵盐(quaternary ammonium salt of chitosan,HTCC)涂膜剂对蓝莓的保鲜作用,在HTCC溶液中分别添加0.5%的丁香和甘草提取液并对蓝莓进行涂膜,研究在4℃下这两种复合涂膜对蓝莓的保鲜效果。结果表明:与单独HTCC涂膜相比,两种复合涂膜均可以降低蓝莓的失重率,减少VC含量和硬度的降低,减缓花青素的变化,具有较好的保鲜效果。且添加丁香提取液的涂膜的保鲜效果要好于添加甘草提取液的涂膜,因此0.5%的丁香提取液可以较好的提高HTCC涂膜的保鲜效果,有利于蓝莓的贮藏。  相似文献   

9.
海带多糖复合涂膜对辣椒保鲜效果的研究   总被引:2,自引:0,他引:2  
采用不同配比的海带多糖复合溶液对辣椒进行涂膜保鲜,研究了海带多糖复合涂膜对室温贮藏期辣椒的过氧化物酶、超氧化物歧化酶、叶绿素、VC、失重率、腐烂率的影响。结果表明:海带多糖复合膜可显著缓解辣椒的失重和腐烂率,降低了过氧化物酶和超氧化物歧化酶活性,并保持有较高的叶绿素和VC含量。配方为2%海带多糖+0.4%壳聚糖+0.2%魔芋葡甘聚糖,对辣椒的保鲜效果最好。  相似文献   

10.
许原  张梦奇 《食品工业科技》2018,39(16):253-257,265
目的:研究肉桂精油、壳聚糖和抗坏血酸3种天然保鲜剂对凤尾菇储藏过程中的保鲜效果。方法:以新鲜凤尾菇为研究对象,分别采用不同浓度肉桂精油、壳聚糖和抗坏血酸对凤尾菇进行处理,结合感官评价找出3种保鲜液的最佳浓度,并研究不同浓度保鲜剂的凤尾菇在5 ℃贮藏过程中感官评价、呼吸强度、褐变度和腐烂指数的变化规律。接着通过正交试验,以3种不同浓度的保鲜剂为考察因素,感官评价与失重率为指标,选出保鲜效果最佳的复合保鲜剂配方。结果:单一涂膜处理时,肉桂精油1.5 g/L、壳聚糖15 g/L和抗坏血酸1.0 g/L具有最好的保鲜效果。最佳的复合保鲜剂配方为,肉桂精油浓度为1.0 g/L、壳聚糖浓度为15 g/L和抗坏血酸浓度为1.0 g/L,该复合保鲜液处理凤尾菇贮藏9 d,感官评分为(78±3)分,失重率为6.98%±0.43%。结论:此复合保鲜液对凤尾菇的保鲜能起到更明显的效果,贮藏期间凤尾菇的品质和色泽均较好。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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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This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

18.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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