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A comparison is made between lysinoalanine (LAL) determinations both with an automatic amino acid analyzer (AAA) and with thin layer chromatography-densitometry (TLC) in different types of food and food ingredients, taken from the Dutch market. Generally there is a reasonable agreement between the LAL content obtained by both methods. However, some results indicate that a single technique is not always conclusive about the real identity of the ninhydrin-positive compound at the same position as LAL on the chromatogram. By TLC for instance, in yeast a content of about 800 mg of LAL/kg in protein is found, but according to the AAA method no LAL is present. In heated milk and milk products the LAL content determined by the TLC method is also higher than that found by the AAA method. This is caused by a preceding unknown ninhydrinpositive compound in TLC, occurring in all heated milk products and practically coinciding with LAL. In the AAA technique similar interferences of unknown ninhydrin-positive compounds could be avoided by choosing a suitable elution temperature; however, application of this temperature modification to foaming agents gave no satisfactory results. © 1978 J. F. Bergmann Verlag. Chemicals/CAS: lysine, 56-87-1, 6899-06-5, 70-54-2; lysinoalanine, 18810-04-3, 23250-50-2; Dietary Proteins; Lysine, 56-87-1; Lysinoalanine, 18810-04-3

According to European Commission (EC) Regulation 1139/98, foods and food ingredients that are to be delivered to the final consumer in which either protein or DNA resulting from genetic modification is present, shall be subject to additional specific labeling requirements. Since 1994, genetically altered tomatoes, squash, potatoes, canola, cotton, and soy have been on the market. Recently, insect-resistant and herbicide-tolerant maize varieties have been introduced. Soy and maize are 2 of the most important vegetable crops in the world. During the past 4 years, both protein-and DNA-based methods have been developed and applied for detection of transgenic soy and maize, and their derivatives. For protein-based detection, specific monoclonal and polyclonal antibodies have been developed; for immunochemical detection, Western blot analysis and enzyme-linked immunosorbent assays are the most prominent examples. For detection of genetically modified organisms (GMOs) at the level of DNA, polymerase chain reaction-based methods are mainly used. For these reactions, highly specific primer sets are needed. This study compares the principally different methods. Specificity of methods and the possible risks of false-positive or false-negative results are considered in relation to sampling, matrix effects, and food processing procedures. In addition, quantitative aspects of protein-and DNA-based GM detection methods are presented and discussed. This is especially relevant as EC regulation 49/2000, which defines a threshold for an unintentional comingling of 1%, came into force on April 10, 2000. Chemicals/CAS: DNA, Plant; Plant Proteins

A liquid chromatographic method with evaporative mass detection (EMD) is described for the determination of paraffins in food contact materials that do not contain polyolefin oligomers, or paraffins migrating from these materials into fatty food simulants or certain simple foods. A normal-phase column operating at maximum column efficiency separates nonparaffinic and paraffinic materials without resolving the latter into individual components, and EMD is used to quantitate the paraffins. An on-line qualitative method that uses liquid chromatography/gas chromatography with flame ionization detection discriminates between paraffin waxes and oils in food contact materials, food simulants, and certain simple foods; a Fourier transform infrared spectrophotometric qualitative method also discriminates between waxes and oils, but is usually restricted to food contact materials that do not contain polyolefins and to migration experiments with organic solvents as fatty food simulants (with some other fatty food simulants, paraffin type must then be identified in the food contact material). Chemicals/CAS: Paraffin, 8002-74-2Chemicals/CAS: Paraffin, 8002-74-2

The well-known Kroller method for the determination of cyanide requires the use of the harmful chemicals benzidine (carcinogenic) and bromine (toxic) in the colorimetric part; the analytical result depends strongly on the conduct of the liberation procedure. The substitution of barbituric acid and N-chlorosuccinimide for benzidine and bromine has been investigated. The reproducibility of both colorimetric reactions is similar, but the sensitivity of the barbituric acid colorimetry is ???50% higher. A reproducible liberation yield can be obtained by a proper control of the heating programme. The detection limit for cyanide in a solution is ???10 ??g/l. ?? 1985 Springer-Verlag. Chemicals/CAS: cyanide, 57-12-5; Cyanides; Indicators and Reagents

Every other year scientists working in the field of residue analysis participate the "International Symposium on Hormone and Veterinary Drug Residue Analysis" and "Euroresidue" conferences. In each symposium a lot of innovative information is presented. In order to obtain a retrieval system for this growing amount of information, a database dedicated to these conferences was created. The main principles of the database were explained during the Fourth Euroresidue Conference (2000, Veldhoven), but it will be extended from subsequent conferences. It is not the aim to compete with other databases but only to have an easy-to-operate database containing information on hormone and veterinary drug residue analysis. In this second edition, the abstracts of all the proceedings have been added. Moreover, the database may be downloaded up-to-date from a website. © 2002 Elsevier Science B.V. All rights reserved.

A study was performed to provide data on the disposition, accumulation and toxicity of sodium iron EDTA in comparison with iron (II) sulfate in rats on administration via the diet for 31 and 61 days. Clinical signs, body weights, food consumption, food conversion efficiency, hematology, clinical chemistry and pathology of selected organs were used as criteria for disclosing possible harmful effects. Determination of iron and total iron binding capacity in blood plasma and non-heme iron analysis in liver, spleen and kidneys were used to assess the disposition and accumulation of iron originating from sodium iron EDTA or iron (II) sulfate. It was concluded that, under the conditions of the present study, iron is accumulated from the diet in liver, spleen and kidneys in a dose-dependent manner, and iron derived from FeEDTA is taken up and/or accumulated less efficiently in liver and spleen than iron from FeSO4. Moreover, feeding iron up to 11.5 and 11.2 mg/kg body weight/day, derived from FeSO4 and FeEDTA, respectively, did not result in tissue iron excess nor in any other toxicologically significant effects. © 2001 Elsevier Science Ltd. Chemicals/CAS: Coloring Agents; Edetic Acid, 60-00-4; Fe(III)-EDTA, 15275-07-7; Ferric Compounds; ferric sulfate, 10028-22-5; Iron, 7439-89-6; Nonheme Iron Proteins

Objective: To describe the rationale and methods for a European project (EFCOSUM) to develop a method for a European food consumption survey that delivers internationally comparable data on a set of policy-relevant nutritional indicators. Rationale and methods: Currently Member States are collecting data and information for use at national level. At an international level, such data are often of limited comparability and of varying quality. To promote the development and exchange of adequate, reliable and comparable indicators of public health, and the structures needed to exchange the relevant data, a programme of Community action on health monitoring was set up for the EU. The objective of the action programme is to contribute to the establishment of a Community Health Monitoring System. Data will be made available to all Member States via a telematic network, which is currently being developed for the Health Monitoring Programme. With regard to nutrition, there is a need for a limited set of policy-relevant dietary indicators that are comparable among EU Member States. In the field of nutrition, however, there is a regrettable lack of internationally comparable data. The project 'European Food Consumption Survey Method' (EFCOSUM) therefore aimed to define a (minimum) set of dietary components which are relevant determinants of health and to define a method for the monitoring of food consumption in nationally representative samples of all age-sex categories in Europe in a comparable way. The project was carried out by 14 Member States as well as nine other European countries. Activities of the project included plenary sessions, desk research, and working group activities, building on existing experience from such projects as DAFNE, EPIC, FLAIR Eurofoods-Enfant project, COST Action 99 and others. The proposed method may be used alone, or as a calibration method to accompany existing ongoing studies. Sponsorship: European Commission, DG SANCO F/3, Health Monitoring Programme. © 2002 Nature Publishing Group All rights reserved.

Objective: To harmonize food classification and food composition databases, allowing comparability of consumption at both food and nutrient levels in Europe. Design: To establish the level of comparability at the food level, the EFCOSUM group benefited from the work already carried out within other European projects, which established a Euro Food Groups (EFG) classification system. Four food groups, ie bread, vegetables (excluding potatoes), fruits (excluding fruit juice) and fish and seafood, were judged on their applicability for making food consumption data comparable across countries at the food level. Conclusions: It was concluded that the EFG system could be used but that still much work has to be done. For food consumption data to be collected in the future, the software that will be used should enable conversion of foods 'as consumed' to foods at the 'raw edible' level. With respect to comparability of nutrient intake estimations, EFCOSUM advises waiting for the European Nutrient Composition Database (ENDB) currently being prepared by the EPIC group. Until this is available, comparison of consumption data at the nutrient level cannot be carried out between countries. Sponsorship: European Commission, DG SANCO F/3, Health Monitoring Programme. © 2002 Nature Publishing Group All rights reserved.

During a period of 2 years, every 2 months 126 different food items forming a 'market basket' were purchased, prepared and divided into twelve food commodity groups. The 'market basket' was based on a study of the dietary pattern of 16- to 18-year-old male adolescents. In the (homogenized) food group various additives and components of nutritional importance were determined. From the concentrations of the additives and components in the food groups and the daily consumption of each food groups, a mean daily intake of all components analysed was calculated. The mean daily amounts of benzoic acid (34 mg), sorbic acid (6 mg), glutamic acid (660 mg) and sulphite (3 mg) were all far below the acceptable daily intake (ADI) value. Butylated hydroxytoluene and gallates were not detectable, while butylated hydroxyanisole (BHA) was found in only a few instances; the maximum amount of BHA was also very low (4 mg). The mean daily intakes of fluorine (0.8 mg), iodine (0.21 mg), phosphorus (1860 mg) and ??-tocopherol (9.4 mg) seem safe and adequate. Cholesterol intakes of 25% above the maximum of 300 mg/d, as advised by the Dutch Bureau for Nutrition Education, were found. The mean fat intake appeared to be 40% of total daily energy, protein content 13% of total energy and total energy and total (available) carbohydrate 46% of total energy. The daily dietary fibre content (18 mg) and the daily amount of linoleic+linolenic acid (6% of total energy) were considered too low. The daily level of sodium (4.2 g) was not considered too high. It is recommended that the study should be repeated regularly, e.g. every few years, in order to monitor trends in the concentrations of significant food components in total diets. Chemicals/CAS: Dietary Carbohydrates; Dietary Fats; Dietary Proteins; Food Additives

In 1989, the Community Bureau of Reference started a research program to improve the quality of vitamin analysis in food. To achieve this task, vitamin methodology was evaluated and tested by interlaboratory studies and the preparation of certified reference materials, which will be used for quality control of vitamin measurements. The main improvements in methodology were achieved by testing and standardizing the extraction condition and enzymatic hydrolysis procedures. Results for each individual material are derived from five replicate determinations using at least two independent methods: Liquid chromatography (HPLC) and microbiological assay for vitamins B1, B2, and B6; and radioprotein binding and microbiological assays for vitamin B12. The certificate of analysis for four reference materials gives mass fraction values for water-soluble vitamins. These certified values were based on the acceptable statistical agreement of results from collaborating laboratories. Certified values with uncertainties (mg/kg dry matter) for each CRM are as follows: 4.63 (0.20) and 4.10 (0.51) for vitamins B1 and B6, respectively, in CRM 121 (wholemeal flour); 6.51 (0.24), 14.54 (0.3), 6.66 (0.43), and 0.034 (0.003) for vitamins B1, B2, B6, and B12, respectively, in CRM 421 (milk powder); 3.07 (0.17) and 4.80 (0.40) for vitamins B1 and B6, respectively, in CRM 485 (lyophilized mixed vegetables), and 8.58 (0.55), 106.8 (2.8), 19.3 (1.5), and 1.12 (0.044) for vitamins B1, B2, B6, and B12, respectively, in CRM 487 (lyophilized pig liver).

An enzyme-linked immunosorbent assay for the detection of mustard protein was developed. The assay is based on a polyclonal antiserum directed against a mixture of mustard proteins raised in rabbits. The assay has a detection limit of 1.5 ppm (milligrams per kilogram) and is suitable for the detection of traces of mustard protein in mustard seed-derived flavoring ingredients. Limited cross-reactivity testing showed that no other plant proteins reacted significantly. From the animal proteins tested, only milk showed some cross-reactivity. With this sensitive assay, it was shown that refined mustard seed oil produced by steam distillation does not contain detectable amounts of mustard protein. Mustard seed oil is used as a flavoring in very low quantities, typically between 40 and 200 mg/kg. Thus, 100 g of a food product flavored with 200 mg of mustard seed oil per kg containing <1.5 mg of protein per kg would represent an amount of mustard seed protein of <30 ng. Taking into account the published literature on allergic reactions to the unintended ingestion of mustard, this conservatively low calculated level indicates that it is unlikely that food products containing mustard seed oil as a flavoring ingredient will elicit an allergic reaction in mustard-allergic individuals. Copyright ©, International Association for Food Protection.

JGZ

Several tests for the detection of soy proteins in foods have been described in the literature, and some are commercially available. This article gives an overview of these methods and discusses the advantages and disadvantages of each individual method. Based on the conclusions of this inventory, an experimental approach was designed to improve the sensitivity of measuring soy protein in processed foods. The aimed sensitivity is 10 ppm (10 μg soy protein in 1 g solid sample), which is over 100-fold lower than presently available tests. The aimed sensitivity is this low because levels of food allergens at 10 ppm and above may provoke reactions in food allergic persons. Native soybean meal, soy protein isolate, soy protein concentrate, and textured soy flakes were used as test materials. Several extraction procedures were compared and a new method using high pH was selected. Polyclonal antibodies were raised in rabbits and goats, and immunopurified antibodies were used in sandwich and inhibition enzyme-linked immunosorbent assay (ELISA). Extraction at pH 12 resulted in good yields for all tested samples, both quantitatively (Bradford) and qualitatively by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Immunopurified rabbit antibodies against this extract used in a competition ELISA format resulted in a sensitive test with a detection limit of 0.02 μg/mL, corresponding to 0.4 μg/g (0.4 ppm) in food samples. Cross-reactivity with some main food ingredients was measured and appeared to be negative in all cases. The presently developed test is applicable for soy ingredients and soy-containing foods that are processed in different ways. The limit of quantitation is 1 ppm, which is an enormous improvement over earlier described methods.

Objective: To examine the hypothesis that there is sufficient agreement between percentage of households purchasing selected foods using household budget surveys and percentage of individuals consuming these foods as determined in individual-based surveys to allow the former to act as a surrogate for the latter when estimating food chemical intakes using household budget data. Design: Database study. Setting: Databases from Sweden, The Netherlands, Ireland and the UK. Subjects: 319 foods (Sweden n = 60, The Netherlands n= 80, Ireland n=90, UK n=89). Results: Pearson correlations demonstrated a high degree of linear association between % households purchasing and % consumers (r=0.86). Regression analysis defined a close positive relationship between the two datasets (slope 0.95, intercept +2.74). Across countries, using the regression equation, the % households predicted % consumers to within 5% of the true value for between 33 and 48% of foods and to within 10% for between 53 and 78% of foods. Conclusions: Values for % households can be used as a crude surrogate for % consumers and can thus play a role in improving estimates of food additive intake.

Hazelnuts are widely used in the food industry owing to their nutritive value and taste. The amount of hazelnut present in a recipe is usually considered as a mark of quality. On the other hand, contamination of foods that normally do not contain hazelnuts is a threat for patients with a hazelnut allergy. For this reason, the availability of a method for the detection and quantification of hazelnuts in foods would be desirable. The objective of this study was to develop a method for the detection and quantification of minor amounts of hazelnut protein in food products that is potentially applicable for the food industry. Several immunochemical methods, e.g., immunoblotting and enzyme-linked immunosorbent assay (ELISA), were developed with antibodies from both hazelnut-sensitized patient sera and the sera of rabbits hyperimmunized with hazelnut protein. Immunoblotting appeared to be non-specific when the sera of patients were used as a source of antibodies. Using immunopurified antibodies from rabbits immunized with hazelnuts, immunoblotting became specific, but the sensitivity of this method was limited. Inhibition of IgE binding is a generally used test in clinical laboratories to establish contamination with hazelnuts. This approach is sensitive and specific, but not readily accessible for the food industry since patient serum is needed. Similar results in terms of sensitivity and specificity were obtained with a sandwich ELISA constructed with an immunopurified antibody from rabbits sensitized to hazelnuts. No substantial cross-reactivity with other nuts, legumes or other food constituents was observed, and concentrations as low as 5 ng/ml, corresponding to 1 ppm in food products, were detected. In a field test, several consumer products regarded to be free of hazelnuts were shown to contain traces of hazelnut. This sandwich ELISA constructed with immunopurified antibodies from rabbits sensitized with hazelnut protein is a sensitive and specific method to detect and quantify hazelnut and is useful in detecting trace contamination with hazelnut in various consumer products. Since this test does not require serum from patients, it is appropriate for use in the food industry. Copyright (C) 1999 Elsevier Science B.V.Chemicals/CAS: Allergens; Immunoglobulin E, 37341-29-0; Plant Proteins

A straightforward and efficient method was developed for the determination of intact daminozide in apples and apple leaves. After extraction with methanol and a clean-up step using a graphitized carbon cartridge, the extract was analysed by ion-trap liquid chromatography-tandem mass spectrometry (LC-MS-MS) using atmospheric pressure chemical ionisation in the positive ion mode. Recoveries for apple were 98-102% with a R.S.D.≤11% (n=6) and for leaves were 112-116% with a R.S.D.≤18% (n=6). The limits of detection were 0.008 and 0.02 mg/kg for apples and leaves, respectively. Copyright (C) 1999 Elsevier Science B.V.

An immunochemical biosensor assay for the detection of multiple mycotoxins in a sample is described.The inhibition assay is designed to measure four different mycotoxins in a single measurement, following extraction, sample clean-up and incubation with an appropriate cocktail of anti-mycotoxin antibodies.The different mycotoxins could be detected simultaneously in relevant concentrations within a time frame of 25 minutes, including the time needed for sensor regeneration.The application of the developed assay on presently available miniature SPR devices allows the development for low-cost instruments, which can be used in field measurements. © 2003 Elsevier Science Ltd. All rights reserved.

A storage study of orange juice packed in oxygen scavenging (OS) film and oxygen barrier film was conducted to determine the extent of ascorbic acid loss due to oxygen as a function of time and temperature. The initial concentration of ascorbic acid in the orange juice was 374 mg/l and this was found to decrease by 74 and 104 mg/l after 3 days of storage at 25°C in the OS and oxygen barrier film, respectively. This rapid loss in ascorbic acid correlated well with the amount of oxygen initially present in the headspace and that dissolved in the juice. The loss of ascorbic acid also correlated with an increase in the browning of the juice, where the extent of browning was found to be lower for the juice packed in the OS film than that packed in the oxygen barrier material. The rapid removal of oxygen was found to be an important factor in sustaining a higher concentration of ascorbic acid over long storage times. Crown Copyright © 2003 Published by Elsevier Science Ltd. All rights reserved.

A trained panel developed a set of sensory attributes describing flavor, odor, mouth feel and after feel sensations elicited by commercially available vanilla custard desserts. Two main sensory dimensions, one running from "melting" to "thick" and another one running from "rough" to "creamy-soft" could be recognized in the resulting sensory space. The commercial custard desserts were well distributed along the rough-creamy dimension but not along the melting-thick dimension. In a second study, model custards were used that varied in levels and type of thickener (carrageenan and starch) and fat content. This resulted in a better distribution of the custard desserts across the sensory space, and in a confirmation of the two main sensory dimensions. The melting-thick dimension was primarily related to thickener content and to the viscosity measured instrumentally. The rough-creamy/soft dimension was primarily related to fat content. High fat custards produced less sensations of dryness and roughness, more sensations of flavor, and more sensations of creamy and fatty mouth and after feel than their zero-fat containing counterparts. This was confirmed by PLS modeling that showed a good prediction of creamy/soft mouth feel sensations from a combination of flavor/taste sensations (creamy and fatty flavors and absence of bitter/chemical and sickly flavors), mouth feel sensations (thickness and fattiness) and after feel sensations (fatty coating and absence of roughness). It is argued that possible mechanisms by which fat affects the attributes that are part of this dimension include lubrication (friction) and flavor release. © 2003 Elsevier Science Ltd. All rights reserved. Chemicals/CAS: carrageenan, 9000-07-1, 9049-05-2, 9061-82-9, 9064-57-7; starch, 9005-25-8, 9005-84-9

This publication is the 12th in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. Since then, the number of flavoring substances has grown to more than 2200 chemically-defined substances. Elements that are fundamental to the safety evaluation of flavor ingredients include exposure, structural analogy, metabolism, toxicodynamics and toxicology. Scientific data relevant to the safety evaluation for the use of aliphatic, linear α,β-unsaturated aldehydes and structurally related substances as flavoring ingredients are evaluated. The group of substances was reaffirmed as GRAS (GRASr) based, in part, on their self-limiting properties as flavoring substances in food; their low level of flavor use; the rapid absorption and metabolism of low in vivo concentrations by well-recognized biochemical pathways; adequate metabolic detoxication at much higher levels of exposure in humans and animals; the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels determined from subchronic and chronic studies. While some of the compounds described here have exhibited positive in vitro genotoxicity results, evidence of in vivo genotoxicity and carcinogenicity occurs only under conditions in which animals are repeatedly and directly exposed to high irritating concentrations of the aldehyde. These conditions are not relevant to humans who consume α,β-unsaturated aldehydes as flavor ingredients at low concentrations distributed in a food or beverage matrix. © 2008 Elsevier Ltd. All rights reserved. Chemicals / CAS: 2 hexenal, 505-57-7; sorbic acid, 110-44-1, 22500-92-1; Aldehydes; Carcinogens; Flavoring Agents; Mutagens