明日叶中营养成分及生物活性物质的检测分析

目的:对明日叶中的营养成分和生物活性物质查尔酮的含量进行检测分析。方法:采用国标法对明日叶中的营养成分含量进行检测分析,并用紫外可见分光光度法测定明日叶中查尔酮的含量。结果:明日叶中含有蛋白质4.71%、还原糖1.65%、粗纤维3.64%、脂肪0.19%、水分84.79%、灰分0.72%,VB10.02mg/100g、VB20.71mg/100g、VC45.90mg/100g、叶酸0.30mg/100g、VB123.20μg/100g,钾110.00mg/100g、钙140.21mg/100g、镁1.50mg/100g、铁14.03mg/100g、锗20.67μg/100g;测得的18种氨基酸含量为2.85g/100g,其中8种人体必需氨基酸含量为1.11g/100g,占18种氨基酸总量的38.9%;生物活性物质查尔酮含量为0.75%。结论:明日叶中含有多种有益于人体健康的营养成分,其中蛋白质含量比常见蔬菜高,其氨基酸模式较为理想,且含有丰富的粗纤维、VC、VB2和叶酸,维生素在叶中的含量尤其丰富,还有植物少有的VB12和有机锗及罕见的生物活性物质查尔酮,具有较高的研究价值和保健功效,应用前景广阔。     

三种功能氨基酸在野生山黄皮果果核中的测定

将采摘自广西区内野生山黄皮主要产地大新、宁明、龙州的山黄皮果实去掉果皮果肉匀浆,经过盐酸水解,或去离子水浸泡,用氨基酸自动分析仪测定了野生山黄皮果果核中精氨酸、γ-氨基丁酸、脯氨酸的组成。结果表明,野生山黄皮果果核中含有丰富的精氨酸、γ-氨基丁酸、脯氨酸。由盐酸水解果核及浸泡两种方法处理后,果核中水解精氨酸的含量为355.29 mg/100 g,游离精氨酸为144.98 mg/100 g;水解脯氨酸的含量为179.62 mg/100 g,游离脯氨酸含量为43.46 mg/100 g;γ-氨基丁酸的含量高达194.78 mg/100 g。     

柞蚕雄蛾浓缩液成分及免疫调节功能的研究

本文对柞蚕雄蛾浓缩液中的部分营养成分及食品卫生指标进行了分析测定,结果表明:18种游离氨基酸总量为1133.6mg/100ml,其中人体必需氨基酸含量达328.7mg/100ml,占总量的29%,赖氨酸含量高达37.7mg/100ml;维生素A含量为1.52IU/100g,VE、VB1、VB2总量为0.992mg/100g;8种矿质元素含量丰富;该浓缩液符合国家食品卫生标准。经对小鼠细胞免疫功能的检测、体液免疫的影响检测和单核吞噬细胞系统功能影响的结果表明:该浓缩液对小鼠具有明显的免疫调节功能。     

虹鳟鱼骨营养成分分析

对虹鳟鱼骨中总蛋白、胶原蛋白、总氨基酸、脂肪与矿物质等营养成分进行分析检测。结果表明:虹鳟鱼骨中总蛋白、胶原蛋白、总氨基酸、脂肪、灰分含量分别为21.32%、4.56%、19.08%、18.38%、11.93%,其中必需氨基酸为22.03%;鱼骨中不饱和脂肪酸和饱和脂肪酸含量分别为13.36g/100g,5.25g/100g,其中二十碳五烯酸(EPA)+二十二碳六烯酸(DHA)含量为3.36g/100g,占脂肪酸含量的18.05%;虹鳟鱼骨中钙、磷、钠、钾含量较高,分别为50252.58mg/kg、32893.20mg/kg、2080.52mg/kg、1113.89mg/kg,同时还含有铁、锌、锰等多种微量元素。虹鳟鱼骨营养丰富,颇具开发利用价值。     

河北省主要杂粮营养成分分析及评价

以河北省产裸燕麦、甜荞、谷、黍等主要杂粮为研究对象,采用现代仪器分析方法对其主要营养成分进行分析和评价。结果表明:小米、裸燕麦中蛋白质含量较高,分别为12.63 g/100 g和12.52 g/100 g,最低的是玉米,仅为7.94 g/100 g;小黄米和大黄米中VB1含量较高,分别为0.34 g/100 g和0.39 mg/100 g,玉米中含量最低,为0.09 g/100 g;甜荞中VE(0.83 mg/100 g)与钙、磷、钾、镁、锌等微量元素含量均高于其他种类杂粮;糜子米中VB2含量较为突出(0.18mg/100 g);裸燕麦中Fe(14.36 mg/100 g)含量丰富;玉米中Se(3.54μg/100 g)含量较高,并含有大量叶黄素(349.56μg/100 g)和玉米黄素(270.90μg/100 g)。营养价值评价结果表明,河北省主要杂粮的蛋白质、VB1、VB2和Ca等重要营养素的营养质量指数(Index of nutrition quality,INQ)均明显高于大米,且糜子米中蛋白质、VB1、VB2均为营养质量合格;甜荞、裸燕麦氨基酸评分较高,其氨基酸含量与FAO推荐值最为接近。因此,河北省产糜子米、甜荞和裸燕麦营养价值较高,具有较大的开发与应用前景。     

单针藻营养成分分析

以单针藻（Monoraphidium dybowskii C29）藻粉为研究对象,分析藻粉中的营养成分。结果表明,藻粉中含有丰富的油脂、粗纤维、蛋白质、多糖和色素,分别占藻粉干重的30.25%、23.77%、20.08%、11.31%和4.22%。矿物质元素中镁、钙、锌和铁含量较高,分别为4 771.90、718.22、48.85、331.44 mg/kg,食品中污染限量元素铅、铬、镉、砷、镍均低于国家标准;含有18种氨基酸,总量为17.68%,必需氨基酸达总氨基酸含量的37.44%,且必需氨基酸指数（EAAI）较高;还含有8种维生素,其中以VB6和VC含量较高,分别为51.26 mg/（100 g藻粉）和19.88 mg/（100 g藻粉）;脂肪酸中含有较高的亚油酸和亚麻酸,质量分数分别为油脂的25.86%和9.27%。单针藻是类营养丰富的藻类,具有开发成为食品和饲料的潜力。     

薏苡不同部位营养成分分析及评价

以贵州兴仁县产薏苡的不同部位为研究对象,分析测定其种仁及非种仁部位的营养成分和功能性成分。结果表明：薏苡6个部位的化学成分含量有一定差异,种仁的蛋白质和多糖类物质含量较高,分别为19.33g/100g和2.26g/100g,VE含量为8.66mg/100g;外壳和种皮的粗纤维含量高;根中VB1和VB2含量较高,分别为0.61mg/kg和2.96mg/kg;矿质元素中K、Na、Ca、Mg等常量元素含量较高;种仁和叶中分析出7种必需氨基酸和10种非必需氨基酸,其余部位均为7种必需氨基酸和9种非必需氨基酸;功能性成分分析中,根的薏苡素和总多酚含量最高,分别为1.26mg/g和4.53mg/g,种仁中总黄酮含量最高,为2.26mg/g。脂肪酸分析中,种皮、茎、叶的不饱和脂肪酸相对含量达到70%以上。因此,薏苡不同部位的营养价值和药用价值高,具有很好的开发前景。     

藏药蕨麻的营养成分分析及评价

进行了蕨麻的常规营养成分及无机微量元素、氨基酸和维生素的分析研究,并与甘薯、马铃薯、芋头、藕粉进行了比较.结果表明,蕨麻的粗蛋白为9.45%,粗脂肪为1.15%,膳食纤维为15.23%,在蕨麻所含的17种氨基酸中,天门冬氨酸占氨基酸总量的14.45%,谷氨酸占13.16%,此外还含有丰富的钙、铜、铁、锌、硒、锗及VC、VNB2、VB6和叶酸等营养物质,其中硒含量达0.27mg/100g,锗含量达0.03mg/100g;VC含量达6.29mg/100g,叶酸含量达1.26mg/100g.     

冬瓜籽油的理化指标及营养成分的分析

对冬瓜籽油的理化性质、脂肪酸组成及营养成分进行分析。结果表明:冬瓜籽油酸价为4.96 mg/g,过氧化值为0.02 g/100 g,皂化值为195.97 mg/g,碘值为111.22 g/100 g;冬瓜籽油中包含12种脂肪酸,其中以亚油酸为主要脂肪酸,不饱和脂肪酸含量高达81.83%;冬瓜籽油还含有丰富的植物甾醇,其中菜油甾醇含量最高,为2 255.50 mg/kg,豆甾醇含量为980.76 mg/kg;冬瓜籽油中共检出3种生育酚,其中γ-生育酚含量最高(612.9 mg/kg),其次为α-生育三烯酚(90.6 mg/kg);冬瓜籽油中多酚类物质的含量为56.4 mg GAE/kg油。     

金耳、银耳与木耳的营养成分比较

采用标准方法对金耳、银耳与木耳的营养成分进行全面的比较分析。结果表明：金耳含有蛋白质12.4%、灰分3.2%、粗纤维2.0%、脂肪2.8%、总糖72.8%,其中蛋白质、脂肪和总糖含量均高于木耳和银耳,而粗纤维低于木耳（7.9%）;金耳中的功能营养成分多糖、多酚、黄酮含量分别为37.8%、0.18%和0.12%,多糖含量显著高于木耳和银耳;金耳的氨基酸总量和鲜味氨基酸含量分别为9.72%和2.25%,均高于银耳和木耳,按照联合国粮农组织和世界卫生组织提出的理想蛋白质条件,3种食用菌作为理想蛋白质来源的优先顺序依次是木耳＞金耳＞银耳;金耳检出6种维生素,VA及 β-胡萝卜素（VA原）、VB1、VB2、VC和 VD3,其中 β-胡萝卜素含量为 2.32 mg/100 g,与绿叶蔬菜相当,3 种食用菌均含有植物中少见的维生素D,含量大小顺序是木耳＞金耳＞银耳,分别为1 588、743、133 μg/100 g,高于肉制品、鸡蛋和鱼类,可作为素食者的维生素D摄入源;我国人群中相对容易缺乏的元素钙、铁、锌在3种食用菌中含量丰富,其中以木耳的钙、铁含量为最高,金耳次之,而金耳锌含量（21.1 mg/kg）为最高,稍低于猪肉（29.9 mg/kg）,铁含量（81.2 mg/kg）比鸡蛋黄（65 mg/kg）更高,3种食用菌重金属锰、铅、砷、镉、汞含量均符合国家限量要求。综上所述,3种食用菌营养素成分齐全、含量丰富,金耳因其含有丰富的多糖、β-胡萝卜素、维生素D、锌和铁,综合营养价值更高。     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.