小龙虾(克氏原螯虾)中铜含量富集现状及其环境来源分析

摘 要: 目的 调查小龙虾及其养殖环境中铜的含量, 探讨小龙虾中铜元素的富集现状及其可能的环境来源。方法 在我国主要的小龙虾养殖产地采集小龙虾及其养殖环境样本(养殖用水、池塘底泥), 采用微波消解法进行消解, 电感耦合等离子体质谱法进行样品中铜含量的测定。结果 小龙虾中铜含量均值为10.22 mg/kg, 积累量按照头壳、背壳、肝胰腺、虾肉依次递减, 其占完整小龙虾中铜积累量比例分别为17.74%、15.97%、8.75%、5.11%。小龙虾中铜含量与其养殖池塘底泥中的铜含量具有正相关性, 相关系数为0.39。A省小龙虾中铜含量显著高于其他地区(P<0.05)。结论 我国小龙虾及其养殖水体中铜含量均在国家规定的标准限量以内, 但部分地区小龙虾养殖池塘底泥中的铜含量超出国家标准, 池塘底泥是小龙虾中铜重要的环境来源, 可能造成潜在风险, 因此, 仍需要加强对小龙虾及其养殖环境中铜含量的监管。     

不同养殖模式和野生克氏原螯虾肌肉营养成分分析与评价

通过测定池塘养殖模式(pond)、稻田养殖模式(paddy)养殖的克氏原螯虾和野生(wild)克氏原螯虾肌肉营养成分的组成和含量,对其营养价值进行综合评价。结果表明:虾肉粗蛋白质含量表现为稻田组(84.42%)>池塘组(83.59%)>野生组(82.81%)(p>0.05);粗脂肪含量表现为稻田组(2.96%)>池塘组(2.22%)>野生组(1.48%)(p<0.05)。池塘组、稻田组和野生组虾肉中∑TAA、∑EAA、∑EAA/∑TAA、∑EAA/∑NEAA、∑DAA/∑TAA表现为,池塘组>稻田组>野生组(p>0.05)。根据AAS,池塘组、稻田组和野生组虾肉的第一限制性氨基酸分别为Thr、Val、Val,第二限制性氨基酸均为Met+Cys;根据CS,其第一限制性氨基酸均为Met+Cys,第二限制性氨基酸分别为Val、Thr、Val。池塘组、稻田组和野生组虾肉中分别检测出13种、14种和15种脂肪酸,其中∑SFA分为48.06%、44.03%、39.95%(p<0.05);∑MUFA分别为35.48%、31.03%、25.76%(p<0.05);∑PUFA分别为16.46%、24.93%、32.30%(p<0.05);n-3/n-6则表现为野生组(0.18)<稻田组(0.24)<池塘组(0.35)(p<0.05)。综上,养殖组(稻田组和池塘组)克氏原螯虾肌肉的综合营养价值比野生组更高。     

江苏省典型稻虾养殖环境和产品重金属分布及风险评价

为探讨江苏部分地区稻田养殖小龙虾养殖环境潜在生态风险和小龙虾中重金属含量分布情况及食用安全性,于2022年3月-6月期间对江苏省稻虾养殖示范基地9个养殖区水质、沉积物和稻虾样品进行采集,并进行重金属含量分析。稻虾水质部分采样点Cu浓度超过有超过GB11607-1989《渔业水质标准》现象,其余四种元素均在限量值范围内。水质综合污染指数评价结果表明该养殖区水质部分时段受到轻微污染影响。沉积物生态风险等级为低风险,Cd是生态风险最大的元素。同一元素在稻虾不同部位的分布有比较显著的差异。部分稻虾肝胰腺砷元素有超标现象,其他四种元素均在GB2762-2017限量值范围内。虾肉、肝胰腺中五种元素THQ值和TTHQ值均小于1,表明长期摄入稻虾虾肉、肝胰腺对人体健康风险不明显,安全性较好。     

小龙虾头营养成分及风味滋味特性分析与评价

为充分利用小龙虾头等副产物,探讨小龙虾头作为食品加工原料的可行性。本文以广西稻田养殖小龙虾头为原料,采用国标测定虾头中蛋白质、脂肪、灰分、氨基酸、脂肪酸等基本营养成分,利用高效液相色谱仪测定虾头中呈味核苷酸和有机酸含量,并通过电子舌和气相离子迁移谱（GC-IMS）对新鲜虾头整体滋味和气味进行分析。结果表明：从营养组成来看,小龙虾头营养丰富,其中主要以粗蛋白（10.92 g/100 g）和粗脂肪（9.05 g/100 g）为主,脂肪中含磷脂4.67 mg/g;虾头中有17种氨基酸,总含量为97.28 mg/g,其中必需氨基酸有7种,占氨基酸总量的50.01%;共检出19种脂肪酸（9种饱和脂肪酸、10种不饱和脂肪酸）,不饱和脂肪酸含有57.94%。从风味组成来看,虾头中的氨基酸、磷脂以及脂肪酸都是重要的风味前体物质;除此之外,在新鲜虾头中游离氨基酸总含量900.70 mg/100 g,鲜、甜味氨基酸占39.88%;虾头中的呈味核苷酸和有机酸也为虾头提供了更为丰富的滋味;并且虾头的电子舌鲜味响应值为13.55,鲜味明显;在虾头中共定性出23种挥发性风味化合物,其中包括醛类、酮类和醇类等,具有...     

生长环境对克氏原螯虾细菌群落多样性的影响

为探索生长环境对克氏原螯虾（Procambarus clarkii）细菌群落多样性的影响,本实验利用Illumina MiSeq测序技术,对克氏原螯虾尾肉、养殖水体及周围土壤进行基因序列测序,分析小龙虾虾肉与其生长环境之间的相关性。多样性分析结果表明,土壤的微生物多样性高于小龙虾和水体多样性,分析三组样品在不同分类水平的相对丰度发现,小龙虾、土壤和水体中有相对固定的优势菌群,在门类为变形菌门（Proteobacteria）和拟杆菌门（Bacteroidetes）,α-变形菌纲（Alphaproteobacteria）、β-变形菌纲（Betaproteobacteria）和δ-变形菌纲（Deltaproteobacteria）等在小龙虾尾肉、土壤及水体中的平均相对丰度较高,而在科和属水平上无共有优势菌群。PICRUSt2代谢功能预测结果表明,3组样品在有氧呼吸（aerobic respiration I）、脂肪酸合成（fatty acid elongation）、氨基酸生物合成（amino acid synthesis）和核糖核苷酸代谢途径（nucleotide sugar metabolism）中代谢通路丰度最高。研究结果进一步解释了生长环境和克氏原螯虾微生物群落结构间的相关性和差异性。     

食用淡水小龙虾存在安全隐患

淡水小咙虾（克氏原螯虾）因其蛋白质和氨基酸含量较高,而成为人们喜食的水产品。但由于小龙虾存在富集重金属、携带肺吸虫或其他病原菌,不良商贩用洗虾粉洗虾等安全隐患,而导致各类疾病发生。因此应采取正确的食用方法并多加注意,如不吃头、鳃、内脏,将虾外壳洗干净,将虾放在清水里养24～36小时后再食用,不吃非养殖虾等,才能将安全隐患将到最小,尽享美食。     

稻田养殖克氏原螯虾中甲基汞的污染特征与食用安全风险评估

目的 探讨我国主产区的稻田养殖克氏原螯虾(Procambarus clarkii)甲基汞(methylmercury,MeHg)累积情况和食用安全风险。方法 利用高效液相色谱-原子荧光联用法(high performance liquid chromatography and atomic fluorescence spectrometry,HPLC-AFS)分析了湖北、湖南和安徽3省9个地市生产的127份稻田养殖克氏原螯虾的MeHg含量。采用单因子污染指数(single-element pollution indices,Pi)和每周可耐受摄入量(provisional tolerable weekly intake,PTWI)、目标危害商值(target hazard quotient,THQ)法分别评价了其污染程度和食用安全性。结果 MeHg的检出率达93.7%,含量范围为0～0.313 mg/kg,所有样品的MeHg含量均未超出国家标准限量值;不同地区稻田养殖克氏原螯虾的MeHg污染程度排序为：湖南>安徽>湖北。膳食暴露评估结果表明成人每周摄入量(estimated weekly intakes,EWI)低于食品添加剂联合国粮农组织和世界卫生组织下的联合专家委员会(Joint Food and Agriculture Organization FAO/World Health OrganizationWHO Expert Committee on Food Additives, JECFA)推荐的食品添加剂的每周可耐受摄入量(PTWI) 。结论 所有稻田养殖克氏原螯虾样品的THQ值均小于1,介于0.044~0.328之间,表明摄入这些地区稻田养殖克氏原螯虾的MeHg暴露风险较低。     

基于微生物指标评价冷冻熟制小龙虾食用安全风险

小龙虾营养美味，但其食用安全性一直困扰消费者，为了探究冷冻熟制小龙虾食用安全风险，本研究首先根据小龙虾样品的总挥发性盐基氮（total volatile basic nitrogen,TVB-N）值和pH值确定食用终点，然后通过高通量测序法分析食用终点小龙虾内脏与鳃、虾肉、虾壳和调味汤料4个部分的微生物菌群结构和群落多样性。结果显示：熟制小龙虾冷冻贮藏过程中，内脏与鳃和虾肉pH值呈缓慢下降趋势，调味汤料和虾壳pH值先上升后下降；各部分TVB-N值均呈上升趋势，贮藏至180 d时虾肉、内脏与鳃的TVB-N值分别为32.42 mg/100 g和31.26 mg/100 g，到达食用终点。高通量测序结果显示，食用终点的熟制小龙虾各部分细菌群落结构存在差异，不同部分菌群丰度由高至低依次为调味汤料、内脏与鳃、虾壳和虾肉，且各部分优势菌属组成不同，其中调味汤料中乳酸杆菌属（Lactobacillus）为优势菌；内脏与鳃中以嗜冷杆菌属（Psychrobacter）和弧菌属（Vibrio）为主；虾壳中优势菌属为弧菌属、乳酸杆菌属和嗜冷杆菌属；虾肉中优势菌属为嗜冷杆菌属和不动杆菌属（Acinetobac...     

低温真空油炸工艺对小龙虾虾尾酥品质的影响

为丰富即食水产品种类,探索真空油炸技术,以单冻小龙虾虾尾为原料,通过低温真空油炸工艺制备小龙虾虾尾酥产品。在单因素试验的基础上,以水分、油脂含量、酥脆性、硬度、丙烯酰胺含量为指标,选择油炸温度、油炸时间、油料质量比和脱油时间为变量,利用正交试验设计对真空油炸工艺进行优化。结果表明,真空油炸工艺的最优条件：真空度0.09 MPa,油炸温度95℃、油炸时间120 min、油料质量比3.0:1.0、脱油时间25 min,此条件下,小龙虾虾尾酥水分含量为（2.65±0.11）%,粗脂肪含量为（25.66±1.88）%,硬度为（443.21±42.36）g,酥脆性与常压油炸小龙虾虾尾酥无显著差别,丙烯酰胺含量为（11.2±0.17）μg/kg。相比于常压油炸,低温真空油炸工艺不仅减少营养损失,而且降低了油脂及丙烯酰胺含量,为提升小龙虾油炸制品品质提供理论依据和科学指导。     

不同地区稻田小龙虾的营养品质比较研究

以来自江苏、安徽、湖北地区的稻田雄性小龙虾为研究对象,对其含肉率、基本成分、矿物质、氨基酸和脂肪酸组成进行分析,评估并比较不同地区稻田雄性小龙虾的营养价值。结果表明,湖北小龙虾的含肉率（11.65%）和粗蛋白（19.04%）含量最高,江苏小龙虾的粗脂肪含量最高（1.10%）。3 个地区小龙虾肉中均检出17 种氨基酸,必需氨基酸含量/总氨基酸含量比为38%～39%,说明虾肉的蛋白质质量较好,其中安徽小龙虾的总氨基酸含量最高。3 个地区的小龙虾中,安徽小龙虾虾肉中的矿物质总量最高,为850.92 mg/100 g,其中Na、K、Ca、P、Fe、Cu含量显著高于其余两地（P＜0.05）。从虾肉的脂肪酸组成来看,江苏小龙虾所含脂肪酸种类最丰富,安徽和江苏小龙虾虾肉中的脂肪酸以多不饱和脂肪酸为主（相对含量分别为43.15%和41.31%）,而湖北小龙虾虾肉中的脂肪酸以单不饱和脂肪酸为主（45.70%）,3 个地区小龙虾虾肉中的不饱和脂肪酸含量占比均在70%以上。     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

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.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

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