处理海水在鱿鱼加工中的应用

采用超滤膜处理结合臭氧技术,将净化海水直接应用到冷冻鱿鱼的解冻清洗加工过程。以菌落总数、pH值、白度、持水力、挥发性盐基氮(TVB-N)以及硫代巴比妥酸(TBA)值为质量指标,研究不同臭氧浓度的净化海水与自来水解冻清洗对鱿鱼品质的影响。结果表明,超滤膜净化海水效果较为显著;随臭氧浓度的增加,鱿鱼的pH值、持水力变化较小,白度值、TBA值逐渐增大,TVB-N值呈现先降后升的变化趋势。经综合评定,当海水中臭氧质量浓度为0.25 mg/L时,可较明显改善鱿鱼品质,延长冷藏鱿鱼片货架期,其处理效果优于同等臭氧浓度的自来水处理效果。     

不同防腐剂对烤制鱿鱼片贮藏品质的影响

为了延长烤制鱿鱼片的货架期,本文采用37 ℃加速破坏实验,分别研究空白组、添加山梨酸钾组、添加乳酸链球菌素（Nisin）组及添加ε-聚赖氨酸盐组的烤鱿鱼片样品在贮藏7 d中理化指标的变化,考察贮藏过程中烤制鱿鱼片的TVB-N含量、菌落总数、微观结构、pH、色泽的变化,并对其进行感官评价,探究不同防腐剂对烤制鱿鱼片贮藏品质的影响。结果表明:在贮藏的第7 d,乳酸链球菌素处理的烤制鱿鱼片的TVB-N含量比山梨酸钾组、ε-聚赖氨酸盐组、空白组降低了2.35、8.123、9.612 mg·100 g?1;空白组和山梨酸钾处理组烤制鱿鱼的菌落总数在第5 d时超过标准,分别为4.59、4.48 lg CFU·mL?1,ε-聚赖氨酸盐处理组烤制鱿鱼片的菌落总数在第6 d时超过国家标准,含量为5.08 lg CFU·mL?1。乳酸链球菌素处理组烤制鱿鱼片的菌落总数在贮藏过程中没有超过国家标准。不同防腐剂处理的烤制鱿鱼的色泽、质构和感官评分差异显著（P<0.05）。与ε-聚赖氨酸盐和山梨酸钾相比,乳酸链球菌素能有效的抑制烤制鱿鱼TVB-N含量、菌落总数的上升,且能减缓烤制鱿鱼质构和色泽的变化,使烤制鱿鱼保持良好的感官性状,是更有利于烤制鱿鱼贮藏的防腐剂。     

解冻方式对近江牡蛎肉感官特征和理化指标的影响

为获得冻结牡蛎肉的最佳解冻方式,以解冻时间、感官评分、质构、色差、解冻损失率、蒸煮损失率、pH、挥发性盐基氮(Total volatile basic nitrogen,TVB-N)、硫代巴比妥酸(Thibabituric acid,TBA)和菌落总数为指标,研究自然解冻、静水解冻、冷藏解冻、超声波解冻和微波解冻5种解冻方式对近江牡蛎感官特征和理化指标的影响,并采用变异系数权重法对解冻后牡蛎肉品质进行综合评价。结果表明:自然解冻(128 min)与冷藏解冻(309 min)所需时间较长,解冻后牡蛎肉的感官评分最小,分别为4.6、4.4分;TVB-N、TBA和菌落总数较大。微波解冻(1.5 min)和超声波解冻(9 min)耗时较短,感官评分较高,分别为6.12、6.0分;TVB-N、TBA和菌落总数最小,但蒸煮损失率和解冻损失率较大。静水解冻所需时间31 min,感官评分(6.0分)较高,但TVB-N、TBA和细菌总数较大。综合评价结果显示,解冻时间(权重值为0.357)对牡蛎肉品质影响最大,微波解冻综合评分(0.548)最高,是理想的近江牡蛎肉解冻方式,但持水力较低,微波解冻条件仍需进一步研究。     

壳聚糖对冷却猪肉品质特性的影响研究

对壳聚糖在贮藏期间对冷却猪肉的感官性状(色泽、持水力)、理化品质(pH值、TBA、TVB-N)和微生物品质(菌落总数)的影响进行研究。添加壳聚糖能够明显的抑制微生物的生长(p<0.05),随着壳聚糖添加浓度的增大,脂质氧化率、挥发性盐基氮增加率及pH值上升率均下降,而持水力则呈现上升趋势。经过1.5%壳聚糖处理的样品在各方面的综合品质最好。     

内源化学反应及细菌活动对冰温贮藏罗非鱼片腐败变质的贡献研究

目的 评估内源化学反应及细菌活动对冰温贮藏罗非鱼片腐败变质的贡献。方法 研究经抑菌处理及未经抑菌处理的罗非鱼片在冰温贮藏期间的菌落总数、挥发性盐基氮(totalvolatilebasicnitrogen,TVB-N)值、pH、硫代巴比妥酸(thiobarbituric acid, TBA)值及感官鲜度的变化,采用电子鼻监测挥发性成分的变化,并对未经抑菌处理罗非鱼片各指标与菌落总数间进行皮尔逊相关性分析。结果 贮藏期间经抑菌处理的样品的菌落总数始终小于5.05 log CFU/g, TVB-N值小于3.00 mg/100 g, pH及电子鼻测定的各种挥发性成分基本未变,未发生感官腐败,虽然TBA值有所增加(P<0.05),但始终低于0.05 mg MDA/100 g。而未经抑菌处理的罗非鱼片,菌落总数在21 d时达到9.19 log CFU/g, TVB-N值增至40.69 mg/100 g, pH由6.65增至7.63,电子鼻测定的氮氧化合物、硫化物及有机硫化物骤增, TBA值增至0.072 mg MDA/100 g,显著高于抑菌处理的样品,感官腐败明显。结论 冰温贮藏条件下内源...     

臭氧水浓度对鳙鱼头减菌效果及鲜度品质的影响

目的 研究不同浓度臭氧水对鳙鱼头减菌效果的影响,确定鳙鱼头最佳臭氧水减菌化条件,为鳙鱼头的冰温保鲜奠定基础。方法 采用气液混合法制备不同浓度的臭氧水,通过菌落总数及TBA值、TVB-N值、K值和pH值反映臭氧水浓度对鳙鱼头减菌效果的影响。结果 高浓度臭氧水能显著提高鱼头的减菌率、降低其TVB-N值和K值(p<0.05),对TBA值及pH值无显著影响(p>0.05)。淋洗时间对鳙鱼头的减菌率有显著影响(p<0.05),对其它指标无显著影响(p>0.05)。结论 用浓度为7.8mg/L臭氧水淋洗处理鳙鱼头5min,其减菌率可达到90.43%,且TBA值、TVB-N值和K值均较低,减菌效果较好。     

超高压处理对养殖大黄鱼保鲜效果的影响

研究超高压处理对养殖大黄鱼保鲜效果的影响,经不同超高压（100、200、300、400、500 MPa,保压时间10、15 min）处理后,研究其pH值、aw、挥发性盐基氮（total volatile basic nitrogen,TVB-N）值、硫代巴比妥酸（thiobarbituric acid,TBA）值、三甲胺（trimethylamine,TMA）值、菌落总数的变化。其次,研究大黄鱼在4 ℃冷藏期间pH值、aw、TVB-N值、TBA值、TMA值、菌落总数的变化情况。结果表明,超高压处理后大黄鱼的pH值随着压力的升高而增加;aw随压力的升高而减小;TVB-N值随着压力的增加呈减小的趋势;TBA值随着压力的上升而增大;TMA值略有上升但幅度不大;菌落总数随压力增加明显降低。实验组的大黄鱼pH值和aw在4 ℃贮藏期先升后降;500 MPa、15 min 处理后45 d,大黄鱼的TVB-N值和TMA值增加,含量分别不超过35 mg/100 g和5 mg/100 g,TVB-N值和TMA值得到了有效控制;第45天500 MPa、15 min处理组大黄鱼的菌落总数为5.7×104 CFU/mL。因此,压强500 MPa保压时间15 min为养殖大黄鱼最适合的保鲜条件。     

臭氧水处理鸭肉冷藏品质的研究

以鸭肉为原料,研究浓度为0、3、5、7、9 mg/kg的臭氧水处理鸭肉4℃冷藏条件下菌落总数、TVB-N、肌纤维蛋白抽提率、TBA、pH、色泽及感官指标的变化规律。随着臭氧水浓度的增加,鸭肉贮藏期间菌落总数、TVB-N值、TBA值相比对照组显著较低(p0.05),肌纤维蛋白抽提率,感官评分值和色度a*值显著较高(p0.05),pH值变化不显著。结果表明:臭氧水处理浓度5mg/kg,温度4℃,时间30 min较为适宜,能有效地抑制贮藏期间鸭肉表面微生物的增长,降低鸭肉蛋白变性速率与脂类氧化速率,保持鸭肉良好的色泽与感官品质。     

板栗壳多酚对冷藏鱼糜制品的保鲜效果研究

为进一步考察板栗壳多酚在冷藏鱼糜制品中的应用效果,探索水产品保鲜新方法,在鱼糜中分别添加0、0.01%、0.02%、0.03%、0.04%、0.05%的板栗壳多酚并制备成鱼丸,真空包装后在4 ℃下冷藏,定期测定样品的微生物学指标、理化指标和质构指标等。结果表明：在4 ℃下,随着贮藏时间的不断增加,鲢鱼鱼丸的菌落总数、TBA值、TVB-N值和硬度均有不同程度的增加,弹性、持水性、白度值和感官评分呈下降趋势,pH值先升高后降低;添加板栗壳多酚的鲢鱼鱼丸菌落总数、TBA值和TVB-N值均低于空白组,持水性、弹性和感官评分均高于空白组。综合冷藏过程中各类指标的变化,板栗壳多酚添加量为0.02%时保鲜效果最好。     

复合保鲜剂对团头鲂尸僵过程中品质变化的影响

为探究壳聚糖、茶多酚、溶菌酶复合保鲜剂对团头鲂尸僵过程中(冷藏72 h)白度、质构、pH值、持水力、挥发性盐基氮(total volatile base nitrogen, TVB-N)、K值和菌落总数的影响,采用正交试验设置复合保鲜剂的配比,以K值和TVB-N为评价指标,确定最佳复配比。结果表明,团头鲂经2%壳聚糖、0.2%茶多酚、0.05%溶菌酶(均为质量分数)复合保鲜剂处理后,其白度、持水力均明显升高,pH值、TVB-N值和菌落总数的上升趋势较对照组更缓,宰后较佳食用时间延长了4 h左右。复合保鲜组的团头鲂在宰杀后48 h内保持一级鲜度,比对照组延长了12 h,且两试验组的团头鲂在72 h内均保持在二级鲜度。研究结果对团头鲂保鲜和加工具有重要意义,也为冷藏及运输过程中的品质管理提供了理论依据。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

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.     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

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.     

European priorities for research to support legislation in the area of food contact materials and articles

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.     

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