葫芦巴精油对采后樱桃番茄果实贮藏品质的影响

以樱桃番茄为试材,用不同浓度的葫芦巴精油在40 ℃条件下熏蒸30 min,将处理后的樱桃番茄恒温贮藏于20 ℃下,分别测定其在贮藏期间过氧化物酶(POD)活性、可滴定酸、可溶性还原糖含量等品质指标的变化,探究在20 ℃储藏条件下葫芦巴精油处理对樱桃番茄果实采后品质的影响。结果表明,葫芦巴精油能够提高樱桃番茄的贮藏效果,其中7.5 μL葫芦巴精油对保持果实的可溶性固形物含量、可滴定酸和可溶性还原糖含量相对较好,10 μL葫芦巴精油能较好保持樱桃番茄的POD活性,延缓Vc含量的下降,减缓果实硬度的变化,使果实的腐烂指数下降。综上可知,7.5～10 μL葫芦巴精油能较好地保持樱桃番茄在20 ℃下的贮藏品质,能够延长樱桃番茄的贮藏时间。     

丁香精油对杧果采后炭疽病及品质的影响

为探究植物精油对杧果采后炭疽病菌的抑菌效果以及植物精油处理后对贵妃杧的采后品质的影响,分别用10种植物精油对杧果炭疽病菌(Colletotrichum gloeosporioides)进行离体抑菌试验;以贵妃杧为试验材料,刺伤后分别用0.0、0.2、0.5、1.0、2.0和4.0μL/mL的丁香精油浸泡5.0 min后接种杧果炭疽病菌,统计炭疽病病斑直径和病情指数;以2.0μL/mL的丁香精油浸泡贵妃杧5.0 min后观察自然发病,统计病情指数和防治效果,同时研究了丁香精油对贵妃杧采后品质的影响。结果表明,离体抑菌试验中,10种供试植物精油对杧果炭疽病原菌的菌丝生体长均有明显的抑制效果,其中丁香精油的抑菌效果最好,EC₅₀值和EC₉₀值分别为0.19μL/mL和0.57μL/mL。在丁香精油对贵妃杧刺伤接种抑制效果试验中发现,贮藏12 d时,2.0μL/mL处理的病斑直径及病情指数均显著低于对照,病斑直径为10.45 mm,病情指数为46.25。同时2.0μL/mL处理能有效预防贵妃杧采后自然发病,且能显著抑制失重和果肉硬度下降,贮藏后期仍保...     

基于高压静电场处理的樱桃番茄果实贮藏期生理品质及其代谢

樱桃番茄色泽艳丽,味道酸甜适口,受到消费者欢迎。但樱桃番茄采后容易腐烂变质,且鲜食时其表面致病菌不利于消费者健康。本实验以‘黄妃’樱桃番茄为材料,通过大肠杆菌菌落总数、腐烂率、生理指标测定以及代谢组学分析,研究高压静电场（high voltage electrostatic field,HVEF）处理对樱桃番茄果实贮藏期生理品质及代谢的影响。结果表明,HVEF处理能显著降低果实表面的大肠杆菌菌落总数（P＜0.05）,并能延缓贮藏期间果实腐烂,且对呼吸速率和质量损失率没有明显影响,果实乙烯释放量在贮藏早期受到抑制。代谢组学分析结果表明,HVEF处理能引起部分代谢物质的含量差异,且存在多种上调和下调模式,其中部分类黄酮和生物碱类物质含量上升。综上,HVEF处理能够降低果实采后腐烂率和表面致病菌数量,并对改善樱桃番茄果实采后品质有一定的作用。     

1-MCP结合哈茨木霉菌对樱桃番茄贮藏的保鲜效果

为探究1-MCP结合哈茨木霉菌对樱桃番茄贮藏品质的影响,以"荣耀F1代"樱桃番茄为试材,对采后樱桃番茄的生理指标、营养指标及相关酶活性进行测定,研究四种处理(采前喷水+蒸馏水熏蒸处理,S1;采前喷3.0×106CFU/m L哈茨木霉菌+蒸馏水熏蒸,S2;采前喷水+0.5μL/L的1-MCP处理,S3; 3.0×106CFU/m L哈茨木霉菌+0.5μL/L的1-MCP处理,S4)在(11±0.5)℃下对樱桃番茄贮藏品质的影响。结果表明:与对照(S1)比较,3种处理均能够抑制果实的腐烂率上升,延缓果实硬度、可溶性固形物、可滴定酸含量和VC含量的下降,降低果实的呼吸强度和乙烯生成速率,保持更好的SOD活性、PPO活性、POD活性和LOX活性,其中S1、S2、S3、S4的腐烂率在贮藏末期(48 d)分别为49.85%、37.89%、28.56%和19.81%。通过比较,采前喷施3.0×10~6CFU/m L哈茨木霉菌结合采后用0.5μL/L的1-MCP来处理樱桃番茄对果实的贮藏效果最好,能够明显延缓樱桃番茄的衰老进程,保持较高的贮藏品质。因此,采前喷施3.0×10~6CFU/m L哈茨木霉菌结合采后用0.5μL/L的1-MCP来处理樱桃番茄对果实的保鲜效果最好。     

丁香精油抑菌及抗氧化作用研究

利用超临界CO2萃取法从丁香中提取精油,研究测定了丁香精油对各种供试菌种的抑菌圈直径,加热处理及pH对丁香精油抑菌效果的影响,同时研究了丁香精油的抗氧化效果。结果表明:丁香精油对各供试菌种的抑菌圈直径在18.0～38.2mm之间,表明丁香精油对G+和G-细菌、霉菌和酵母均有很强的抑制作用;丁香精油的抑菌效果随pH的降低而增强;121℃/15min加热处理对丁香精油的抑菌效果无明显影响;丁香精油还具有一定的抗氧化性能。     

施硒对樱桃番茄贮藏品质及3种活性氧代谢酶的影响

为探寻施硒对樱桃番茄采后贮藏品质的影响并确定其适宜的处理浓度,在樱桃番茄发育过程中分次冲施不同浓度硒肥,分析番茄果实采收时及在贮藏过程中果实硬度、色泽、乙烯释放量、糖、酸、V_C含量及活性氧代谢相关酶活性的变化情况。结果表明,采收时2 mg/L硒处理的樱桃番茄果实硬度、可溶性糖含量、V_C含量与对照组相比分别增加了7.98%、5.29%和11.32%,并在贮藏过程中始终维持较高含量;同时2 mg/L硒处理提高了采后果实过氧化物酶活性(40.01~64.24 U/g)和超氧化物歧化酶活性(36.94~186.39 U/g);并在乙烯释放高峰时期(21 d)抑制乙烯释放量至8.01 μL/kg·h,延缓了樱桃番茄果实的采后衰老。而3 mg/L硒处理在贮藏42 d时对果实的活性氧代谢酶表现出负面影响,过氧化氢酶、过氧化物酶、超氧化物歧化酶活性分别低于对照组11.93%、23.09%和31.01%,不利于维持番茄果实的贮藏品质。2 mg/L为适宜的采前硒处理浓度,可以提升樱桃番茄果实品质及贮藏特性。     

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...     

采前3 种杀菌剂喷施对樱桃番茄采后品质的影响及啶菌噁唑残留检测

以金珠樱桃番茄为试材,研究采前杀菌剂喷施对采后樱桃番茄发病率、质量损失率和食用品质的影响,并测定樱桃番茄果实中啶菌噁唑残留变化。结果表明：采前喷施杀菌剂显著降低了金珠樱桃番茄采后发病率,提高了樱桃番茄果实中VC和可溶性固形物含量,减缓了VC和可溶性固形物含量贮藏期间的损失;但对质量损失率和可滴定酸含量的影响不显著（P＜0.05）。对樱桃番茄采后贮藏保鲜效果最好的杀菌剂为啶菌噁唑,喷施质量浓度为0.4 g/L。采前喷施啶菌噁唑后,樱桃番茄中啶菌噁唑残留在采前和采后均呈下降趋势;且采后樱桃番茄中啶菌噁唑残留下降的速度比采前下降的慢,贮藏温度越低,下降越慢。     

Iturin A与肉桂精油复配提升樱桃番茄贮藏品质

为探究抗菌肽iturin A与植物精油复配对樱桃番茄的保鲜效果,在测定精油对软腐病菌(Rhizopus stolonifer)最小抑菌浓度(minimum inhibitory concentration,MIC)的基础上,确定iturin A和精油的最佳浓度,研究了樱桃番茄贮藏品质的变化。结果表明,iturin A的MIC为64μg/mL,肉桂精油的MIC为0. 05%(体积分数),在8种植物精油中最低;当单独使用质量浓度为512μg/mL的iturin A和体积分数为1%的肉桂精油处理时,樱桃番茄软腐病发病率最低;另外,当512μg/mL iturin A与1%(体积分数)肉桂精油复配使用时,能显著降低樱桃番茄腐烂率,减缓色差的变化和硬度的下降,延缓可滴定酸、VC、还原糖的含量的下降。当贮藏15 d时,复配组腐烂率和失重率分别为7. 18%和0. 72%,显著低于对照组的55%和8. 91%。Iturin A与肉桂精油复配能够有效保持樱桃番茄品质,延长贮藏时间,保障食品的安全性,为生物保鲜技术提供理论依据。     

贝莱斯芽孢杆菌发酵液对樱桃番茄贮藏品质的影响

樱桃番茄富含营养,在采后贮藏过程中其品质受到各种因素的影响而下降,为提高采后果实品质并延长货架期,亟待寻求一种安全有效的保鲜措施。以综合性评价、感官属性及风味与营养3个方面为评价指标,探究贝莱斯芽孢杆菌A4发酵液对樱桃番茄的保鲜效果。结果表明贝莱斯芽孢杆菌A4发酵液明显降低樱桃番茄的腐烂率和失重率,贮藏第12天,对照组腐烂率为27.97%,而发酵液处理组腐烂率为6.38%,且处理组的失重率显著低于对照组。贝莱斯芽孢杆菌A4发酵液可保持樱桃番茄的硬度、脆性、紧实度,延缓可滴定酸、可溶性固形物、类黄酮、番茄红素、酚类物质的损失,具有显著的保鲜效果。进一步探究发现贝莱斯芽孢杆菌A4发酵液可提高樱桃番茄超氧化物歧化酶（superoxide dismutase,SOD）、过氧化物酶（peroxidase,POD）、丙氨酸解氨酶（phenylalanine ammonia lyase,PAL）3种抗性酶的活性,并能够抑制丙二醛（malondialdehyde,MDA）的积累,从而保持樱桃番茄的贮藏品质。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

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.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

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.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<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     

Chinese CTP Market

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%.     

Preparatory Work of Print China 2015 is Going Smoothly

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     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.