Metrohm 892 Professional Rancimat, Руководство пользователя

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4.3 Determinations
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892 Professional Rancimat
NOTICE
If the isolated oil/fat samples are not immediately analyzed, you
have to store the samples
in a cool place and protected from
light ; for storing the samples, you should cover them in their ves-
sels with a nitrogen layer. This type of storage does not provide
complete protection against unintended and uncontrolled changes
in the oxidation stability, but it represents a useful preservation in
many cases.
You can find further information on the treatment of oil and fat samples in
Rancidity in Foods , Allen J.C., Hamilton R.J., Applied Science Publishers ,
London and New York, 1983.
Preparing emulsion fats
You can use emulsion fats like pure substances and prepare them as fol-
lows:
1 Weighing in the sample
￭
Weigh in the sample.
NOTICE
As the water evaporates right at the beginning of the analysis and
is carried away by the air blown through, you have to use corre-
spondingly more sample material.
2 Mounting the foam barrier
￭
Mount the foam barrier ( see figure 9, page 17 ), as the samples
can foam heavily .
NOTICE
If the emulsion fat samples are not immediately analyzed, you
need to store the samples
in a cool place and protected from
light ; for storing the samples, you should cover them in their ves-
sels with a nitrogen layer. This type of storage does not provide
complete protection against unintended and uncontrolled changes
in the oxidation stability, but it provides useful preservation in
many cases.