超声波促渗对蒸煮鸭心食用品质的影响

对超声波应用于蒸煮鸭心促进腌制液的渗透及其对鸭心食用品质的影响进行了研究。以鸭心为原料,采用超声波(300 W;40 k Hz)辅助蒸煮,并测定了食盐含量、嫩度、蒸煮损失的变化及蛋白质变性程度。结果表明,处理时间为25 min时,超声波处理组中鸭心的食盐含量及嫩度比传统加热煮制组分别显著提高了29.4%、26.9%(P0.05);蒸煮损失显著下降了30.8%(P0.05);蛋白质变性程度显著增大(P0.05)。因此,超声波处理可有效促进腌制液的渗透、改善嫩度、降低蒸煮损失,从而在实际生产中可改善鸭心制品的品质,提高生产效率。     

超声波辅助腌制法对牦牛肉腌制速率和品质影响的研究

传统腌制方法耗时长,腌制效率低。研究目的在于探讨超声波辅助腌制法对牦牛肉腌制速率、嫩度和蒸煮损失的影响。选择0、120、210 W和300 W超声功率,用1%、4%、5%和6%氯化钠腌制牦牛肉,进行30、60、90 min和120 min超声处理,测定亚硝酸钠渗透深度、氯化钠含量、剪切力、蒸煮损失。在此基础上,利用L9(34)正交试验对超声波辅助腌制牦牛肉的功率、超声时间和氯化钠浓度等工艺条件进行优化,以亚硝酸钠渗透深度确定超声波辅助腌制法对牦牛肉腌制的速率、剪切力和感官评价等影响。结果表明,超声波辅助腌制能加快腌制液向牦牛肉肌肉组织渗透的速率,加快腌制的速度,还能减少腌制牦牛肉的蒸煮损失,增加保水性,提高肉的嫩度。超声功率210 W、超声时间60 min、氯化钠浓度为6%时,超声波辅助腌制牦牛肉的品质最佳,腌制速率也有所提高。     

冷熏虹鳟鱼生产工艺研究

本文主要是介绍了虹鳟鱼的加工过程中通过对加工时间的控制来观察对肉的嫩度及感观的影响。随着腌制时间的增加,产品感观评分增加,但是当腌制时间继续延长,感观评分急剧下降,一般在40～60min为益。干燥时间对鱼肉嫩度的影响比较大,随着干燥时间的延长,鱼肉中的水分大量流失,肉嫩度值增加;干燥100～140min对于产品的感观评价较好。最后确定出烘干时间对于产品的嫩度和感观评价影响最明显,腌制时间次之,确定出最佳工艺参数,即腌制50min,干燥120min,熟制90min,烟熏液浓度0.1%.     

超声波法对鸭肫腌制效果的影响研究

以腌制品水分含量和食盐含量为主要指标,探讨采用超声波技术对鸭肫腌制效果的影响研究。试验结果表明:超声波能有效促进盐分扩散与提高样品持水力,以食盐含量和水分含量为考核指标的最优超声处理工艺条件分别为超声功率140W、超声作用时间100min、超声作用温度29℃、腌制液浓度16%和超声功率120W、超声作用时间100min、超声作用温度32℃、腌制液浓度16%。     

超声波处理辅助腌制对酱牛肉品质影响的研究

考察超声波辅助处理腌制酱牛肉的效果,先将大块牛肉浸没在一定浓度腌制液中,再采用超声波(功率为500W,频率为25kHz)分别超声处理0、40、80、120、160和200min后,测定牛肉中氯化钠含量、亚硝酸钠渗透深度、剪切力、蒸煮损失、透射电镜及感官评价得分。结果表明:超声波处理能有效地促进酱牛肉的腌制速度和改善酱牛肉嫩度,其中超声处理160min时牛肉可提前达到腌制平衡;透射电镜结果显示超声波能有效破坏肌肉组织,促进腌制;超声波处理组的感官评定的总体可接受性得分也较高。因而,超声波辅助处理能够简化酱牛肉腌制工艺,提高产品质量。     

不同频率超声波处理对低盐咸肉腌制的影响

主要研究经不同频率超声波处理后的肉在腌制期间的腌制效应。结果表明,超声波处理可加速肉块食盐的渗透,缩短腌制时间,28kHz的超声波比40kHz的超声波更能促进食盐的渗透(P<0.01)。色泽方面,不同频率超声波处理间无显著差异。超声波处理能加速蛋白质分解,促进脂肪的分解和氧化作用,28kHz超声波比40kHz超声波具有更强的促进分解和氧化作用。     

不同腌制方式对猪肉品质的影响

为了选择适合企业生产要求和安全高效的肉制品腌制工艺,本试验以新鲜猪背脊肉为原料,分别采用真空腌制(-86 kPa),高压腌制(150 MPa)以及传统腌制方式,分析腌制效果(水分含量、食盐含量、亚硝酸钠残留量)、PH、食用品质(保水性、色泽、嫩度与质构)、腌肉中盐溶性蛋白含量的变化及影响。结果表明:真空腌制可显著提高猪肉pH值和食用品质,真空腌制对猪肉的嫩度、TPA和色泽有显著影响(P0.05),腌肉中的盐溶性蛋白质的含量随着腌制时间延长,呈上升趋势。腌制6 h时,真空腌制肉中的盐溶性蛋白含量显著高于传统腌制和高压腌制(P0.05)。腌制液中的盐溶性蛋白含量随着腌制时间延长,也呈上升趋势。在腌制6 h时,高压腌制液中的盐溶性蛋白含量显著低于真空腌制组(P0.05)。真空组含量均显著高于传统腌制和高压腌制肉样的亚硝酸钠含量(P0.05)。     

超声波处理对湿腌猪肉腌制速度及肉质的影响

主要研究了超声功率、超声时间与间歇时间比、超声时间对湿腌猪肉腌制速度及肉质的影响。实验结果表明,超声波处理可以加速腌制液中食盐、亚硝酸盐和蔗糖向湿腌猪肉的渗透,加快腌制速度,并且增加肉的保水性,提高肉的嫩度,将蒸煮损失控制在合理范围之内。通过L9(34)正交实验得到超声波最佳处理工艺条件为超声功率300W,超声时间与间歇时间比1∶1,超声处理时间90min。     

牛肉的超声波快速腌制与嫩化工艺优化

采用可控温的三频段超声波处理机,以牛肉为研究对象,以腌制牛肉样品的蒸煮损失、亚硝酸钠渗透深度、氯化钠含量和剪切力为测定指标,以静止湿腌肉样为对照,研究不同超声处理条件对牛肉腌制与嫩化效果的影响。选择超声频率分别为22、28、40 k Hz,超声功率分别为180、240、300 W,腌制温度分别为6、8、10℃,处理时间分别为30、60、90、120、150、180、210、240 min,进行单因素试验,再以剪切力和亚硝酸钠渗透深度为测定指标,通过L9(34)正交试验对牛肉的超声波快速腌制工艺条件进行优化。结果表明:超声频率28 k Hz、超声功率180 W、超声温度8℃、超声时间180 min条件下牛肉的保水性和嫩度最优,与静止湿腌相比,超声波腌制速率大大提高,腌制时间缩短了1/3,牛肉嫩度提高了38%。     

超声波辅助恒温动态循环腌制盐焗鸡翅技术研究

针对盐焗鸡生产工艺中腌制工序时间长、效率低的缺点,以冰冻鸡翅为研究对象,进行超声波辅助恒温动态循环腌制技术研究。考察了超声作用时间、超声波功率、腌制温度和盐水浓度等因素对鸡翅中Na Cl含量、游离氨基酸和挥发性盐基氮的含量的影响,通过正交实验优化了腌制工艺条件。结果表明:各因素对Na Cl含量、游离氨基酸和挥发性盐基氮的含量均有明显影响。超声波辅助恒温动态循环腌制鸡翅的最佳工艺参数为超声作用时间为60min,超声波功率为335W,超声腌制温度为50℃,腌制液盐浓度为6%。此条件下测得鸡翅肉中Na Cl含量为2.01%,游离氨基酸为94.35mg/100g,挥发性盐基氮9.31mg/100g。超声波辅助恒温动态循环腌制能促进食盐的渗透速率,缩短腌制时间,提高游离氨基酸的含量,有利于产品滋味和风味的形成。     

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