SIST EN ISO 6800:1998

Animal and vegetable fats and oils - Determination of the composition of fatty acids in the 2-position of the triglycerides molecules (ISO 6800:1997)

Specifies the method for tensile testing of thin film materials with length and width under 1 mm and thickness under 10  m, which are main structural materials for micro-electromechanical systems (MEMS), micromachines and similar devices.
The main structural materials for MEMS, micromachines and similar devices have special features such as typical dimensions in the order of a few microns, a material fabrication by deposition, and a test piece fabrication by non-mechanical machining using etching and photolithography. This International Standard specifies the testing method, which enables a guarantee of accuracy corresponding to the special features.

Tierische und pflanzliche Fette und Öle - Bestimmung der Zusammensetzung von Fettsäuren in der 2-Stellung von Triglyceridmolekülen (ISO 6800:1997)

Diese Internationale Norm legt ein Verfahren zur Bestimmung der Zusammensetzung von Fettsäuren fest, die in 2-Stellung (beta-oder Innenstellung) der Triglyceridmoleküle in tierischen und pflanzlichen Fetten und Ölen verestert sind. Wegen der Wirkung der Pankreaslipase ist das Verfahren nur auf Fette und Öle mit einem Schmelzpunkt unter 45°C anwendbar.

Corps gras d'origines animale et végétale - Détermination de la composition des acides gras en position 2 dans les triglycérides (ISO 6800:1997)

La présente Norme internationale spécifie une méthode de détermination dans les corps gras d'origines animale et végétale de la composition de la fraction des acides gras estérifiés en position 2 (position β ou position interne) dans les triglycérides. En raison des particularités d'action de la lipase pancréatique, la méthode s'applique seulement aux corps gras ayant un point de fusion inférieur à 45 °C. Elle n'est pas applicable sans restrictions à tous les corps gras, en particulier à ceux renfermant des quantités importantes -- soit d'acides gras ayant 12 atomes de carbone ou moins (par exemple huiles de coprah et de palmiste, matières grasses butyriques du beurre); -- soit d'acides gras ayant 20 atomes de carbone et plus et d'insaturation élevée (plus de quatre doubles liaisons) (par exemple huiles de poissons et d'animaux marins); -- soit d'acides gras possédant des fonctions oxygénées secondaires.  
NOTE -- Les acides gras avec doubles liens en position (n-16) à (n-11) (par exemple acide pétrosélinique) ne sont convertis que très lentement par lipase pancréatique, ce qui pourrait donner des résultats erronés.

Živalske in rastlinske maščobe in olja - Določevanje sestave maščobnih kislin na drugem ogljikovem položaju molekul triglicerida (ISO 6800:1997)

General Information

• Status: Published
• Publication Date: 31-Oct-1998
• ICS: 67.200.10 - Animal and vegetable fats and oils
• Technical Committee: KŽP - Agricultural food products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Nov-1998
• Due Date: 01-Nov-1998
• Completion Date: 01-Nov-1998
• Ref Project: EN ISO 6800:1997 - Animal and vegetable fats and oils - Determination of the composition of fatty acids in the 2-position of the triglycerides molecules (ISO 6800:1997)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 6800:1998
01-november-1998
äLYDOVNHLQUDVWOLQVNHPDãþREHLQROMD'RORþHYDQMHVHVWDYHPDãþREQLKNLVOLQQD
GUXJHPRJOMLNRYHPSRORåDMXPROHNXOWULJOLFHULGD,62
Animal and vegetable fats and oils - Determination of the composition of fatty acids in the
2-position of the triglycerides molecules (ISO 6800:1997)
Tierische und pflanzliche Fette und Öle - Bestimmung der Zusammensetzung von
Fettsäuren in der 2-Stellung von Triglyceridmolekülen (ISO 6800:1997)
Corps gras d'origines animale et végétale - Détermination de la composition des acides
gras en position 2 dans les triglycérides (ISO 6800:1997)
Ta slovenski standard je istoveten z: EN ISO 6800:1997
ICS:
67.200.10 5DVWOLQVNHLQåLYDOVNH Animal and vegetable fats
PDãþREHLQROMD and oils
SIST EN ISO 6800:1998 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 6800:1998

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SIST EN ISO 6800:1998

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SIST EN ISO 6800:1998

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SIST EN ISO 6800:1998

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SIST EN ISO 6800:1998

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SIST EN ISO 6800:1998
INTERNATIONAL ISO
STANDARD 6800
Second edition
1997-12-15
Animal and vegetable fats and oils —
Determination of the composition of fatty
acids in the 2-position of the triglyceride
molecules
Corps gras d'origines animale et végétale — Détermination de la
composition des acides gras en position 2 dans les triglycérides
A
Reference number
ISO 6800:1997(E)

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SIST EN ISO 6800:1998
ISO 6800:1997(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national standards bodies (ISO member bodies). The work of
preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which
a technical committee has been established has the right to be represented
on that committee. International organizations, governmental and non-
governmental, in liaison with ISO, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 6800 was prepared by Technical Committee
ISO/TC 34, Agricultural food products, Subcommittee SC 11, Animal and
vegetable fats and oils.
This second edition cancels and replaces the first edition (ISO 6800:1985),
which has been technically revised.
Annexes A to C of this International Standard are for information only.
©  ISO 1997
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii

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SIST EN ISO 6800:1998
©
INTERNATIONAL STANDARD  ISO ISO 6800:1997(E)
Animal and vegetable fats and oils — Determination of the
composition of fatty acids in the 2-position of the triglyceride
molecules
1 Scope
This International Standard specifies a method for the determination of the composition of fatty acids
which are esterified in the 2-position (ß or internal position) of the triglyceride molecules in animal and
vegetable fats and oils.
Because of the nature of pancreatic lipase action, the method is applicable only to fats and oils with a
melting point below 45 °C.
The method is not unreservedly applicable to all fats and oils, particularly those containing substantial
amounts of
- fatty acids with 12 or fewer carbon atoms (e.g. copra oil, palm kernel oil, butyric butter fats);
- fatty acids with 20 and more carbon atoms and of a high degree of unsaturation (more than four
double bonds) (e.g. fish oil and marine animal oil);
- fatty acids which have secondary groups containing oxygen.
NOTE — Fatty acids with double bonds in the (n-16) to (n-11) position (e.g. petroselinic acid) are converted only
very slowly by pancreatic lipase. This may lead to wrong results.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of
this International Standard. At the time of publication, the editions indicated were valid. All standards are
subject to revision, and parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the standards indicated below.
Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 660:1996, Animal and vegetable fats and oils – Determination of acid value and of acidity.
ISO 661:1989, Animal and vegetable fats and oils – Preparation of test sample.
ISO 3696:1987, Water for analytical laboratory use – Specification and test methods.
ISO 5508:1990, Animal and vegetable fats and oils – Analysis by gas chromatography of methyl esters
of fatty acids.
1

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SIST EN ISO 6800:1998
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ISO
ISO 6800:1997(E)
1)
ISO 5509:— Animal and vegetable fats and oils – Preparation of methyl esters of fatty acids.
3 Principle
After neutralization, where necessary, of any free fatty acids, purification of the test portion by column
chromatography. Partial enzymatic hydrolysis of the glycerides to yield 2-monoglycerides. Separation of
the monoglycerides by thin-layer chromatography (TLC) and determination of their fatty acid
composition by gas chromatography.
4 Reagents
Use only reagents of recognized analytical grade and water in accordance with grade 2 of ISO 3696.
4.1 Reagents for the purification of the test portion
4.1.1 2-Propanol, or ethanol, 95 % (V/V).
4.1.2 Hexane (if available) or light petroleum (boiling range 30 °C to 60 °C).
4.1.3 2-Propanol, 50 % (V/V), or ethanol, 50 % (V/V).
4.1.4 Sodium hydroxide, 0,5 mol/l solution.
4.1.5 Phenolphthalein solution, 1 g per 100 ml of ethanol, 95 % (V/V).
4.1.6 Activated neutral alumina, for chromatography, Brockmann activity l, recently activated for 2 h
at 260 °C and kept in a desiccator.
4.1.7 Nitrogen.
4.2 Reagents for hydrolysis of the triglycerides
4.2.1 Diethyl ether, free from peroxides.
4.2.2. Hydrochloric acid, 6 mol/l solution.
4.2.3 Sodium cholate, 1 g/l solution of enzymatic quality.
4.2.4 Calcium chloride, 220 g/l solution.
2)
, 2-amino-2-(hydroxymethyl)propan-1,3-diol , 1 mol/l, adjusted to pH 8 with
4.2.5 Buffer solution
hydrochloric acid (4.2.2) using a pH-meter.
Store this solution at between 0 °C and 4 °C and use within 14 days.

1) To be published. (Revision of ISO 5509:1978)
2) Alternative names are: tris(hydroxymethyl)methylamine; tris(hydroxymethyl)aminomethane.
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SIST EN ISO 6800:1998
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ISO 6800:1997(E)
4.2.6 Pancreatic lipase, with an activity of between 8 and 20 units/mg.
Store dry in a refrigerator. Before use, bring a portion of the powder to ambient temperature.
NOTE — Lipase of suitable activity is available commercially. If preferred, the lipase may be prepared and assayed
in accordance with the procedure described in annex A.
4.3 Reagents for the isolation of the 2-monoglycerides
4.3.1 Ethanol, 95 % (V/V).
4.3.2 Hexane (if available) or light petroleum, boiling range 30 °C to 60 °C.
4.3.3 Acetone.
4.3.4 Silica powder, with binder, for thin-layer chromatography.
4.3.5 Developing solvent, prepared as follows:
hexane (if available) or light petroleum: 70 ml
diethyl ether: 30 ml
formic acid, 98 % ( ) min.: 1 ml
V/V
, indicator solution, 2 g/l in ethanol, rendered slightly alkaline by
4.3.6 2',7'-Dichlorofluorescein
addition of a drop of 1 mol/l sodium hydroxide per 100 ml of the solution.
4.4 Reagents for the analysis of the 2-monoglycerides by gas chromatography
See ISO 5508 and ISO 5509.
5 Apparatus
Usual laboratoy equipment and, in particular, the following.
5.1 Apparatus for the purification of the test portion
5.1.1 Water bath, thermostatically controlled, and capable of being maintained at 30 °C to 40 °C.
5.1.2 Glass column, for chromatography, 13 mm internal diameter and 400 mm in length, equipped
with a sintered glass plate and a tap.
5.1.3 Rotary evaporator, with 250 ml flask.
, for bubbling nitrogen.
5.1.4 Tubing
, of 500 ml capacity.
5.1.5 Separating funnel
5.1.6 Round-bottom flask, of 100 ml capacity.
3

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ISO 6800:1997(E)
5.2 Apparatus for the hydrolysis of the triglycerides
5.2.1 Centrifuge.
5.2.2 Centrifuge tube, glass, of 10 ml capacity, with ground stopper.
5.2.3 Vibrating electric shaker, for vigorous agitation of the centrifuge tube.
5.2.4 Water bath, thermostatically controlled, and capable of being maintained at 40 °C ± 0,5 °C.
5.2.5 Hypodermic syringe, of 1 ml capacity, with thin needle.
5.2.6 Stopwatch.
5.3 Apparatus for the isolation of the 2-monoglycerides
5.3.1 Developing tank, for thin-layer chromatography, with ground glass lid, suitable for containing
glass plates 200 mm x 200 mm.
, for preparation of the plates.
5.3.2 Spreader and rack
, 200 mm x 200 mm.
5.3.3 Glass plates
5.3.4 Microsyringe, capable of dispensing drops of 3 μl to 4 μl.
5.3.5 Apparatus for spraying the indicator solution onto the plates
5.3.6 Microspatula.
5.3.7 Oven, capable of being maintained at 103 °C ± 2 °C.
5.3.8 Ultraviolet lamp, for examining chromatographic plates, for example with a wavelength of
254 nm.
, of 25 ml capacity, with of approximately 1 m length, with
5.3.9 Round-bottom flask air condenser
ground joint.
5.3.10 Conical flask, of 250 ml capacity, with ground stopper.
5.3.11 Conical flask, of 50 ml capacity (if necessary).
5.3.12 Filter, of sintered glass, porosity P 40 (16 μm to 40 μm) (if necessary).
5.3.13 Desiccator, containing an efficient desiccant.
5.4 Apparatus for the analysis of the 2-monoglycerides by gas chromatography
See ISO 5508 and ISO 5509.
6 Sampling
It is important that the laboratory receive a sample which is truly representative and has not been
damaged or changed during transport and storage.
4

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SIST EN ISO 6800:1998
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ISO 6800:1997(E)
Sampling is not part of the method specified in this International Standard. A recommended sampling
[1]
method is given in ISO 5555 .
7 Preparation of test sample
Prepare the test sample from the laboratory sample in accordance with ISO 661.
8 Procedure
NOTE — If it is required to check whether the repeatability requirement (see 10.2) is met, carry out two single
determinations in accordance with 8.1 to 8.6.
8.1 Determination of the acidity of the test sample
Determine the acidity of the test sample in accordance with ISO 660.
If the acidity is below 3 % (m/m), purify the sample through alumina in accordance with 8.3.
If the acidity exceeds 3 % (m/m), first neutralize the sample with sodium hydroxide in the presence of
solvent in accordance with 8.2 then purify through alumina in accordance with 8.3.
8.2 Neutralization with sodium hydroxide
Dissolve about 10 g of the test sample in 100 ml of hexane (if available) or light petroleum (4.1.2) and
transfer the solution to the separating funnel (5.1.5). Add 50 ml of 2-propanol or ethanol (4.1.1), a few
drops of phenolphthalein solution (4.1.5) and a volume of sodium hydroxide solution (4.1.4) equivalent
to the free acidity of the fat or oil, with an excess of 0,5 %. Shake vigorously for 1 min, add 50 ml of
water, shake again and allow to stand. When separated, run off the lower layer containing the soap and
any intermediate layers (mucilages and insoluble substances). Wash the hexane or light petroleum
solution of the neutralized oil with successive 25 ml or 30 ml portions of a solution of 2-propanol or
ethanol (4.1.3) until the pink colour of the phenolphthalein disappears.
Transfer the solution to the rotary evaporator flask (5.1.3) and remove most of the solvent by
evaporating under reduced pressure. Dry the oil at 30 °C to 40 °C under reduced pressure using a
nitrogen stream (4.1.7) until the solvent is completely removed.
8.3 Purification of the test portion through alumina
Prepare a suspension of 15 g of activated alumina (4.1.6) in 50 ml of hexane (if available) or light
petroleum (4.1.2) and pour, while shaking, into a glass column for chromatography (5.1.2). Ensure that
the alumina settles evenly and allow the solvent level to fall to 1 mm to 2 mm above the upper level of
the adsorbent. Carefully pour into the column a solution prepared by dissolving a test portion of 5 g,
neutralized if necessary, in 25 ml of hexane (if available) or light petroleum (4.1.2) and collect all the
liquid which elutes from the column in a 100 ml round-bottom flask (5.1.6).
Remove most of the solvent by evaporation under reduced pressure, then dry the oil at 30 °C to 40 °C
using a nitrogen stream (4.1.7) until the solvent is completely removed.
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8.4 Hydrolysis of the triglycerides
8.4.1 Weigh approximately 0,1 g of the purified test portion (8.3) in a 10 ml centrifuge tube (5
...