Chemie a potravinářství

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 275 (Food analysis - Horizontal methods)
Původce: CEN
K připomínkám do: 25.09.2018
Zobraz více Zobraz méně
 

This document describes a procedure for the determination of nivalenol (NIV), deoxynivalenol (DON) and its acetyl derivatives (3-acetyl-DON and 15-acetyl-DON), HT-2 and T-2 toxins (HT-2, T-2) and zearalenone (ZEA) in cereals and cereal products by high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS/MS) after cleanup by solid phase extraction (SPE).

The method has been validated with both contaminated and spiked samples of wheat, wheat flour, and wheat crackers.

Validation levels for NIV ranged from 27,7μg/kg to 377,8 μg/kg.

Validation levels for DON ranged from 233,9μg/kg to 2420,0 μg/kg.

Validation levels for 3-acetyl-DON ranged from 18,5μg/kg to 136,5 μg/kg.

Validation levels for 15-acetyl-DON ranged from 11,4μg/kg to 141,8 μg/kg.

Validation levels for HT-2 ranged from 6,6 μg/kg to 133,8 μg/kg.

Validation levels for T-2 ranged from 2,1 μg/kg to 37,6 μg/kg.

Validation levels for ZEA ranged from 31,6μg/kg to 229,7 μg/kg

Laboratory experiences have shown that this method is also applicable to barley and oat flour, and rye based crackers [5], however, this has not been validated in a collaborative study.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 25.09.2018
Zobraz více Zobraz méně
 

This document specifies a method for determining the flow time of paints, varnishes and related products that can be used to control consistency.

1.2     Four flow cups of similar dimensions, but having orifice diameters of 3 mm, 4 mm, 5 mm and 6 mm, are specified. Two methods for checking the flow cups for wear and tear are given (see Annex A).

Flow cups with a replaceable jet are not covered by this International Standard as the close tolerances on the supply of the material under test to the jet are not met.

Commonly used dipping flow cups are also not covered by this International Standard. In general, the fabrication tolerances for such flow cups are greater than those of the flow cups specified in this International Standard. Therefore flow time determinations with dipping flow cups give a precision which is lower than that obtained with the flow cups specified in this International Standard (see Clause 9).

1.3     The method is limited to testing materials for which the breakpoint of the flow from the orifice of the flow cup can be determined with certainty. This point is difficult to determine and reproduce for materials with flow times near the upper limit of the measurement range (100 s) due to slowing-down effects.

1.4     Flow times are reproducible only for products of Newtonian or near-Newtonian flow properties. This effectively limits their practical use. Nevertheless, for checking purposes, these flow cups do serve a useful purpose. Furthermore, the measurement of flow time is often used to confirm the application consistency.

Paints often contain flow-arresting agents to confer increased viscosity. Such paints exhibit non-Newtonian flow properties. Their viscosity during application can only be properly assessed using viscometers such as that described in ISO 3219.

Resins and varnishes can exhibit Newtonian or near-Newtonian flow at much higher viscosities than most paints and, where this applies, flow cups can provide a useful means of controlling the consistency. To meet this requirement, this International Standard provides flow cups suitable for viscosities up to about 700 mm2/s.

With thixotropic materials, stirring or other such mechanical disturbance immediately before testing will reduce the flow time compared with that for an unstirred sample. With such materials, uncertain and variable flow time values are obtained with all the flow cups. The repeatability and reproducibility limits given in Clause 9 cannot be achieved in the determination of the flow time of such materials.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 25.09.2018
Zobraz více Zobraz méně
 

This part of ISO 1518 specifies a test method for determining under defined conditions the resistance of a single coating or a multi-coat system of paint, varnish or related product to penetration by scratching with a scratch stylus loaded with a specified load. Penetration of the stylus is to the substrate, except in the case of a multi-coat system, in which case the stylus can penetrate either to the substrate or to an intermediate coat.

The method specified can be carried out

a)     either as a “pass/fail” test, by testing with a single specified load applied to the stylus to assess compliance with a particular specification;

b)    or as an assessment test by applying increasing loads to the stylus to determine the minimum load at which the coating is penetrated.

Neither this part of ISO 1518 nor ISO 1518‑2 specifies a method using a curved stylus, which is specified in ISO 12137. The choice between the three methods will depend on the particular practical problém.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 25.09.2018
Zobraz více Zobraz méně
 

This part of ISO 1518 specifies a method for determining, using a pointed stylus loaded with a continuously increasing load, the scratch resistance of a single coating of a paint, varnish or related product, or the upper layer of a multicoat system.

This test has been found to be useful in comparing the scratch resistance of different coatings. It is most useful in providing relative ratings for a series of coated panels exhibiting significant differences in scratch resistance.

Neither this part of ISO 1518 nor ISO 1518‑1 specifies a method using a curved stylus, which is specified in ISO 12137. The choice between the three methods will depend on the particular practical problém.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 275 (Food analysis - Horizontal methods)
Původce: CEN
K připomínkám do: 26.09.2018
Zobraz více Zobraz méně
 

This document describes a screening method for the determination of aflatoxin B1, deoxynivalenol, fumonisin B1 and B2, ochratoxin A, HT-2 and T-2 toxins, and zearalenone in foodstuffs by high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS/MS).

The aim of the screening method is to test compliance of foodstuff with regulatory limits or to determine whether a certain pre-defined level (the screening target concentration, STC) is exceeded or not. The result of the screening is either “negative” or “suspect”. “Negative” (screen negative) means that the targeted mycotoxins are not detected or potentially present but below the STC. “Suspect” (screen positive) means that the established cut-off level is exceeded and the sample can contain one or more mycotoxins at a level higher than the STC.

For full identification and accurate quantification a second confirmatory quantitative analysis method is required which is outside the scope of this document.

The method is suitable for various types of foodstuff and has been validated for representative matrices from four commodity groups:

—   high starch and/or protein content and low water and fat content: wheat, cereal mixture, wheat flour and cornflakes;

—   high oil content: peanuts;

—   high sugar low water content: figs;

—   high water content: grape juice.

During validation, cut-off levels were established for the following screening target concentrations:

—   aflatoxin B1: 2 µg/kg to 5 µg/kg;

—   deoxynivalenol: 250 µg/kg to 865 µg/kg;

—   fumonisin B1: 200 µg/kg to 790 µg/kg;

—   fumonisin B2: 110 µg/kg to 230 µg/kg;

—   ochratoxin A: 4 µg/kg to 9 µg/kg;

—   T-2 toxin: 25 µg/kg;

—   HT-2 toxin: 25 µg/kg to 50 µg/kg;

—   zearalenone: 30 µg/kg to 100 µg/kg.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 1.10.2018
Zobraz více Zobraz méně
 

This document specifies a gas chromatographic method with electron capture detection (ECD) for the determination of organochlorine pesticides (OCP’s) in animal feeding stuffs.

The method is applicable to animal feeding stuffs with a water content up to about 20 % by weight and oil/fatty samples containing residues of one or more of the following OCP’s, toxaphene and some of their isomers and degradation products:

—    aldrin;

—    dieldrin;

—    chlordane (as the sum of chlordane isomers and oxychlordane);

—    dichlorodiphenyltrichloroethane (DDT) (as the sum of isomers op'-DDT, pp'-DDT, pp'-TDE (pp'-DDD), and pp'-DDE);

—    endosulfan (as the sum of α-/β-isomers and endosulfan-sulphate);

—    endrin (sum of endrin and delta-keto-endrin);

—    heptachlor (as the sum of heptachlor and heptachlor epoxide);

—    hexachlorobenzene (HCB);

—    hexachlorocyclohexane isomers α-HCH (α-BHC), β-HCH (β-BHC), γ-HCH (γ-BHC or lindane);

—    photo heptachlor;

—    cis- and trans-nonachlor;

A limit of quantification (LOQ) for the mentioned OCPs of 5 ng/g is intended to be obtained. However, 10 ng/g applies for heptachlor, aldrin, endrin, dieldrin, and endosulfan (α-/β– and sulphate). Individual laboratories are responsible for ensuring that the equipment that they use, achieves these limits of quantifications. The LOQs apply to the individual OCPs.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 1.10.2018
Zobraz více Zobraz méně
 

This document specifies a gas chromatographic mass spectrometric (GC-MS) method for the determination of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in animal feeding stuffs and oil.

The method is applicable to animal feeding stuffs consisting of less than 20 % by mass and oil/fatty samples containing residues of one or more of the following OCPs and PCBs and some of their isomers and degradation products:

—    aldrin;

—    dieldrin;

—    chlordane, as the sum of chlordane isomers and oxychlordane;

—    dichlorodiphenyltrichloroethane (DDT), as the sum of isomers op'-DDT, pp'-DDT, pp'-TDE (pp'-DDD), and pp'-DDE;

—    endosulfan, as the sum of α-/β-isomers and endosulfan-sulphate;

—    endrin, as the sum of endrin and delta-keto-endrin;

—    heptachlor, as the sum of heptachlor and heptachlor epoxide;

—    hexachlorobenzene (HCB);

—    hexachlorocyclohexane isomers α-HCH (α-BHC), β-HCH (β-BHC), γ-HCH (γ-BHC or lindane);

—    photo heptachlor;

—    cis- and trans-nonachlor;

—    non dioxin-like PCBs (ndl-PCBs), as the sum of PCB 28, 52, 101, 138, 153 and 180.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 1.10.2018
Zobraz více Zobraz méně
 

This document method is applicable for the determination of theobromine in compound feed by liquid chromatography with UV detection in the tested range of 27 mg/kg to 307 mg/kg. This method has been validated using complementary compound feed for adult dogs and complementary compound feedstuff for horses. The actual working range can extend beyond the tested range. Alternative chromatography conditions using liquid chromatography tandem mass spectrometry (LC-MS/MS) are also provided for the validated range of 49 mg/kg to 307 mg/kg. This method has also been shown to be fit for purpose for the determination of theobromine in baking chocolate by both HPLC-UV and LC-MS/MS.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 1.10.2018
Zobraz více Zobraz méně
 

This part of ISO 8504 describes the general principles for the selection of methods for the preparation of steel surfaces before application of paints and related products. It also contains information on features that must be taken into account before certain surface preparation methods and preparation grades are selected and specified.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 8.10.2018
Zobraz více Zobraz méně
 

This document specifies a high performance liquid chromatographic – tandem mass spectrometry (LC-MS/MS) method for the simultaneous screening and/or determination of the eleven authorized coccidiostats (halofuginone, robenidine hydrochloride, nicarbazin, diclazuril, decoquinate, monensin sodium, salinomycin sodium, narasin, lasalocid sodium, semduramicin sodium and maduramicin ammonium alpha) contents in poultry, cattle and pig feed at additive and cross-contamination levels and of five non-registered coccidiostats (ethopabate, clopidol, ronidazole, dimetridazole and amprolium) at sub-additive levels and for the screening of the prohibited furazolidone antibiotic at sub-additive level, in the same matrices.

The range of application of the method is fit for the purpose of the screening and determination of all eleven coccidiostats at the values set by European legislation, of the non-registered coccidiostats and of the screening of the banned antibiotic.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 8.10.2018
Zobraz více Zobraz méně
 

This document specifies a method for the determination of organic acids in animal feeding stuffs by Ion Chromatography with conductivity detection (IC-CD).

The method is intended to be used for the determination of formic acid, lactic acid, propionic acid, citric acid, fumaric acid and malic acid as active substances in feed additives, premixtures, compound feed and water and for screening of acetic acid in the same matrices. This method determines the total extractable concentration of the above mentioned organic acids and their salts.

It is advisable that the user of this standar determine the working range of the method for each organic acid. The lower limit of the working range depends on the matrix and the interferences encountered. A working range between 10 [mg/l] and 100 [mg/l] should be achievable.

The method was successfully tested in an inter-laboratory study in concentrations between 0,02 % up to 27 % of the above mentioned organic acids.

NOTE          Limitation occurs during simultaneous determination of high concentration of lactic acid and low concentration of acetic acid. If the ratio of concentration of lactic acid to acetic acid exceeds factor 20, the determination of acetic acid is not guaranteed.

On the basis of the referred working range, sample weight and extraction volume, limits of quantification (LOQ), as calculated (Table 1) should be achievable.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 327 (Animal feeding stuffs: Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 8.10.2018
Zobraz více Zobraz méně
 

This document specifies a method for the determination of benzoic acid and sorbic acid in animal feeding stuffs by high-performance liquid chromatography method with ultraviolet detection (HPLC-UV).

The method is intended to be used for the determination of benzoic acid and sorbic acid as active substances in feed additives, premixtures and compound feed and for benzoic acid in water. This method determines the total extractable concentration of these organic acids and their salts.

It is advisable that the working range of the method is determined for each organic acid by the user of this standard. The lower limit of the working range depends on the matrix and the interferences encountered. It is advisable that a working range between 5 mg/l and 100 mg/l is accessible.

The method was successfully tested in an inter-laboratory study in concentrations between 0,02 % up to 9,0 %.

On the basis of the referred working range, sample weigh and extraction volume, limits of quantification (LOQ), as calculated (Table 1) on the basis of a wavelength of 230 nm, can be achievable.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 15.10.2018
Zobraz více Zobraz méně
 

This document describes methods of scribing coated steel or test-pieces for corrosion tests, where the coating system is applied at dry film thicknesses of less than 500 μm. It is intended as a guideline only, being based on the results of a collaborative trial with no subsequent corrosion testing having been carried out to determine the suitability of the introduced scribe marks for such tests.

This document covers the scribing of metallic panels or test pieces (chemically treated or not) made from:

—    steel,

—    galvanized steel,

—    aluminium alloys,

—    magnesium alloys.

It does not cover the scribing of electroplated metal or clad aluminium panels.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 307 (Oilseeds, vegetable and animal fats and oils and their by-products - Methods of sampling and analysis)
Původce: CEN
K připomínkám do: 20.10.2018
Zobraz více Zobraz méně
 

This International Standard specifies a rapid method for extraction of oil and for preparation of the methyl esters of fatty acids. The methyl esters thus obtained can be used for gas chromatography.

This International Standard is applicable to the following oilseeds: rape, sunflower, soya beans, mustard, linseed.

NOTE          Applying this rapid method to high erucic acid content rapeseed leads to an overestimation of erucic acid content by approximately a mass fraction of 1 %. This difference was observed in the study [6] and may be due to the partial extraction of the oil from the sample (yield around 70%). High content of erucic acid in triglycerides could increase their solubility in hexane because of the lipophilic effect of the carbon long-chain (C22). However, as this effect was not checked on a large set of high erucic rapeseed samples, it is not recommended to apply a correction factor to the erucic acid content when analysing high erucic acid rapeseed.

Oblast zaměření: Povrchově aktivní látky
Komise : CEN/TC 276 (Surface active agents)
Původce: CEN
K připomínkám do: 22.10.2018
Zobraz více Zobraz méně
 

This European Standard sets requirements for bio-based surfactants in terms of properties, limits, application classes and test methods. It lays down the characteristics and details for assessment of bio-based surfactants as to whether they:

—    are fit for purpose in terms of performance related properties;

—    comply with the requirements regarding the health, safety and environment which apply to general surfactants;

—    are derived from a certain minimum percentage of biomass; and

—    comply with at least similar sustainability criteria as comparable (non-bio-based) surfactants.

The criteria of the regulation on Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) [11] also apply to bio-based surfactants.

NOTE          EN 16575 defines the term “bio-based” as derived from biomass and clarifies that “bio-based” does not imply “biodegradable”. In addition, “biodegradable” does not necessarily imply the use of “bio-based” materiál.

Komise : CEN/TC 139 (Paints and varnishes)
Původce: CEN
K připomínkám do: 4.11.2018
Zobraz více Zobraz méně
 

This document (ISO 6504‑3) specifies methods for determining the hiding power given by paint coats of white or light colours of tristimulus values Y and Y10 greater than 25, applied to a black and white chart, or to a colourless transparent foil. In the latter case the tristimulus values Y and Y10 are measured over black and white panels. Subsequently, the hiding power is calculated from these tristimulus values.

This document specifies also a simple method for calculating the spreading rate for paints with a volatile matter content with low evaporation speed, e.g. coatings for interior walls and ceilings as specified in EN 13300.

Oblast zaměření: Potravinářské produkty
Komise : CEN/TC 307 (Oilseeds, vegetable and animal fats and oils and their by-products - Methods of sampling and analysis)
Původce:
K připomínkám do: 6.11.2018
Zobraz více Zobraz méně
 

The purpose of this document is to describe a procedure for the determination of the ester content in fatty acid methyl esters (FAME) intended for incorporation into diesel oil. It also allows determining the linolenic acid methyl ester content. It allows verifying that the ester content of FAME is greater than 90 % (m/m) and that the linolenic acid content is between 1 % (m/m) and 15 % (m/m).

This method is suitable for FAME which contains methyl esters between C6 and C24.

NOTE 1       For the purposes of this document, the terms “% (m/m)” and “% (v/v)” are used to represent respectively the mass and volume fractions.

NOTE 2       This method was elaborated for FAME samples from usual raw material. For FAME sample from unidentified raw material, a solution of the test sample is prepared without any internal standard addition, in order to verify the absence of natural nonadecanoic acid methyl ester.

NOTE 3       The distribution off fatty acid methyl esters is given in Annex C.

WARNING — The use of this method may involve hazardous equipment, materials and operations. This method does not purport to address to all of the safety problems associated with its use, but it is the responsibility of the user to search and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.