鱼精粉替代仔猪日粮中进口鱼粉的对比试验

本试验选用健康仔猪１６头，随机分为二组，分别饲喂鱼粉日粮（对照组）与鱼精粉代替日粮（试验组）。通过３１ｄ饲养试验与消化试验，结果表明，鱼粉组与鱼精粉组试猪日头均采食量、平均日增重、饲料增重比、日粮粗蛋白表观消化率分别为９９０ｇ、１０２６ｇ；４４６ｇ、４６１ｇ；２．２２、２．２３；７６．３０％、７８．１０％。使用鱼精粉替代进口鱼粉单位增重料成本下降２％．证明鱼精粉足以完全替代进口鱼粉。     

缓冲剂对乳母牛采食量 瘤胃pH值产乳量和乳成分的影响

缓冲剂主要作用于瘤胃、肠道、血液和乳腺组织等。可提高牛瘤ｐＨ值，提高饲草和有机物的消化率以及菌体蛋白合成，增进乳腺对乳前体物的吸收，增强血浆缓冲能力等。在低饲草或以青贮玉米为唯一饲草的日粮中添加缓冲剂除可提高瘤胃ｐＨ值、乳脂率和增加瘤胃中挥发性脂肪酸产量外，还可提高日粮消化率，增加母牛采食量和防止母牛酸中毒。在炎热季节还可减轻热应激。     

肉牛玉米淀粉的消化率及其对氮沉积和能量转化效率的影响

研究了不同水平过瘤胃玉米淀粉量对能量代谢和氮沉积的影响。试验按４ ×４ 拉丁方设计,四头成年肉牛按１．２ 倍维持（１ ．２Ｍ） 饲养水平供给羊草,在此基础上过瘤胃生玉米淀粉量分别为０、３００ 、６００ 和９００ｇ／ｄ ,结果如下：过瘤胃玉米淀粉量为３００ 、６００ 和９００ｇ／ｄ 时玉米淀粉的瘤胃后消化率分别为６１ ．６３ 、７０ ．７８ 和５３．６４％ 。与对照组相比,过瘤胃玉米淀粉水平的增加可以提高可消化氮转化为沉积氮的效率（ＲＮ／ＤＮ） 和沉积氮（ＲＮ） ,ＲＮ（ｇ／ｄ）、ＲＮ／ＤＮ与过瘤胃玉米淀粉量（ｇ／ｄ） 之间有正相关,相关系数分别为０ ．９８８５ 和０ ．９６５７;过瘤胃玉米淀粉量３００、６００、９００ｇ／ｄ 与对照组相比,净能／ｋｇ 代谢体重（ＮＥｇ／Ｗ０ ．７５） 有极显著地提高（Ｐ＜ ０．０１）,代谢能转化为体增重的效率（Ｋｆ） 分别为４８ ．２９ 、５５ ．９６ 、５５．２２ 和３６．１３％ ;Ｋｆ（ ％ ） 与过瘤胃玉米淀粉量（ｘ,ｇ／ｄ） 的回归方程为：Ｋｆ＝ ３４ ．０９３９ｘ０．０７０１７ ,ｎ ＝１６,ｒ＝ ０．９９０９。     

双低菜籽粕在生长肥育猪日粮中的应用研究

选取新英系大白生长肥育猪（去势公猪）６０头,随机分为５组（每组１２头,两个重复）、分前期（３０－６０kg)和后期（６０－９０kg)两阶段进行饲喂试验,对照组（第１组）为豆粕组,试验组（第２,３,４,５组）日粮中双低菜籽粕的用量比例,前期分别为８％,１０％,１３％,１６％,后期分别为１３％,１６％,１８％,２１％,平衡日粮可消化赖氨酸。结果表明：前期各组平均日增重（ＡＤＧ）差异不显著（Ｐ＞０．０５）;后期第５组与第１,２组差异显著（Ｐ＜０．０５）。试验组日采食量（ＡＤＦＩ）降低,后期更突出。料肉比（Ｆ／Ｇ）前期各组基本相当,后期及全期第４组最好。第３,４,５组腹泻频率升高。试验猪各组日粮的干物质消化基本接近。第４,５组的粗才能量消化率低于第１,２,３组,试验各组猪的胴体品质未受影响,第１,２,３,４组的甲状腺相对重量差异不显著（Ｐ＞０．０５）,第１,２,３组的与第５组差异显著（Ｐ＜０．０５）;第４组与第５组差异不显著（Ｐ＞０．０５）。     

气相色谱法测定奶粉中的EPA和DHA

本文采用气相色谱法测定奶粉中的ＥＰＡ和ＤＨＡ。ＦＩＤ检测定量。本方法的最低检测线：ＥＰＡ为２．０×１０－９ｇ；ＤＨＡ为５．０×１０－９ｇ。变异系数：ＥＰＡ为ＣＶ％＝２．３７；ＤＨＡ为ＣＶ％＝２．６２。平均回收率：ＥＰＡ为９７．８４％；ＤＨＡ为９７．９１％。     

日粮添加肉碱对早期断奶仔猪生产性能的影响

２１日龄平均体重为５．８５ｋｇ的断奶仔猪６４头,按随机区组设计分４组,肉碱添加水平依次为：０,５０,１００和１５０ｍｇ／ｋｇ。各阶段及全程试验结果表明：各组平均日增生（ＡＤＧ）以３组（１００ｍｇ／ｋｇ添加组）最高,但差异不显著;３组平均日采食量（ＡＤＦＩ）比１组（０组添加组）或２组（５０ｍｇ／ｋｇ添加组）显著提高７．７％￣１５．２％（Ｐ〈０．０５）;各组饲料转化效率（ＦＣＲ）及血清尿素氮（ＳＵＮ）     

溢酸宝对仔猪日粮营养物质消化率影响的探讨

以５头断奶仔猪进行两期消化试验。第一期为对照组，饲喂基础日粮，第二期为试验期，饲喂添加０．１５％溢酸宝的基础日粮，采用内源指示剂法测定日粮中营养物质消化率，试验结果，试验期日粮中粗蛋白，总氨基酸，粗脂肪。粗纤维，钙和磷的表观消化率分别为８６．６１％、８４．６６％、６８．０３％、２７．１８％、８４．７１％和６３．３２％。比对照期分别提高９．３７％（Ｐ〈０．０１），９．７６％（Ｐ〈０．０１），１１．０     

色相色谱法测定奶粉中的EPA和DHA

本文采用气相色谱法测定奶粉中的ＥＰＡ和ＤＨＡ。ＦＩＤ检测定量。本方法的最低检测线：ＥＰＡ为２．０×１０＾９ｇ；ＤＨＡ为５．０×１０＾－９ｇ。变异系数：ＥＰＡ为ＣＶ％＝２．３７；ＤＨＡ为ＣＶ％＝２．６２。平均回收率：ＥＰＡ为９７．８４％；ＤＨＡ为９７．９１％。     

甜菜颗粒替代玉米对奶牛消化及瘤胃消化动力的影响

试验使用4头安装有瘤胃瘘管和十二指肠套管的处于泌乳后期的中国荷斯坦奶牛,研究了甜菜颗粒替代玉米对荷斯坦奶牛消化和瘤胃消化动力的影响。试验日粮中粗饲料(玉米青贮+紫花苜蓿)占40%,精饲料占60%,精饲料中的玉米分别用0%、6%、12%和24%的甜菜颗粒进行替代(干物质基础)。4个处理组日粮中的中性洗涤纤维和淀粉的质量分数分别为(24.3%,34.5%)、(26.2%,30.6%)、(28.0%,26.5%)和(31.6%,18.5%)。结果表明,随着甜菜颗粒替代玉米比例的提高,瘤胃干物质周转率下降,瘤胃中性洗涤纤维的周转率提高;潜在降解中性洗涤纤维在瘤胃中的降解率提高,而且降解的速率也提高了,最终日粮总消化道的中性洗涤纤维的消化率提高了。不可消化中性洗涤纤维的瘤胃外排速率并没有受到不同处理的影响。瘤胃淀粉的消化率随着甜菜颗粒替代玉米比例的提高而显著下降,但是,总肠道淀粉的消化率并没有受到影响。随着甜菜替代玉米比例的提高,日粮纤维的消化率显著提高,淀粉的消化率没有受到影响。因此,处于泌乳后期的奶牛在低粗饲料饲喂条件下,日粮中15%~20%的玉米可以用甜菜颗粒进行替代。     

测定加酶日粮氨基酸表观消化率的Sibbald"TME"法比较研究

试验选用15羽伊莎成年公鸡,随机分成3组,采用添加和不添加酶制剂的加酶与常规对照两种日粮,按Sibbald“TME”法测定氨基酸表现消化率的要求,设计成常规日粮预试和强饲、常规日粮预试和加酶日粮强饲、加酶日粮预试和强饲3种程序,研究比较酶制剂及不同的测定程序对氨基酸测定结果的影响,并确定Ssibbald“TME”法测定加醇日粮氨基酸表现消化率的合理程序。研究结果表明：(1)预试常规日粮并强饲加酶日粮与强饲常规日粮相比较,提高了大部分氨基酸的表现消化率,总必需氨基酸及总氨基酸消化率分别提高了0．63％和1．70％;(2)预试并强饲加酶日粮与预试并强饲常规日粮相比较,可使绝大部分氨基酸的表观消化率均有所提高,总必需氨基酸及总氨基酸消化率分剐提高了2．49％和4．0l％;与预试常规日粮并强饲加酶日粮组相比,总必需氨基酸及总氨基酸消化率分剐提高了1．85％和2．28％。(3)采用Sibbald“TME”法测定家禽加酶日粮氨基酸消化率时预试采用加酶日粮为宜。     

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.