Laboratory catalogue

When the liquids are mixed, a considerable amount of
heat is given off. The gas built up in this way can cause the
stopper to shoot out, or the butyrometer may even break.
The butyrometer casing is intended merely as a safety
precaution. Instead of using a butyrometer casing, the
butyrometer can be wrapped in a cloth.
Too lax shaking of the butyrometer or unnecessarily
holding it in a slewed position inhibits quick mixing
and therefore also the rapid oxidation of the whole of
the liquid and can thus ruin the careful work done trying
to get the layering right.
Fig. 4
The centrifuge must be fitted withan interlocking lid.
After the time set for the centrifuge has been reached,
the rotor brake is automatically applied.
Fig. 3
The butyrometer in the casing is shaken. (Protective goggles and rubber
gloves must be worn)
6. Immediately after the mixture has been shaken
and turned upside down a few times, the butyrometers,
still hot and with the stoppers pointing
downwards, are placed in bushings inside the
heated Gerber centrifuge, whereby the butyrometers
must be placed exactly opposite one another
Beforehand, the stopper should be turned to set
the column of fat at the height of the expected
level of fat.
After setting the time on the centrifuge, the centrifuge
is started. The corresponding speed of
(1100 ± 50) rpm, which is reached after 1 min. as a
rule, should be maintained for 4 minutes after
attaining a centrifugal force of (350 ± 50) g.
Fig. 5
The butyrometers are brought to the exact reading temperature in a water
bath
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