Animal fats and oils, their practical production, properties, falsification and examination / by Louis Edgar Andés. Tr. from the German by Charles Salter.

  • Andés, Louis Edgar, 1848-1925.
Date:
1904
Catalogue details

Licence: In copyright

Credit: Animal fats and oils, their practical production, properties, falsification and examination / by Louis Edgar Andés. Tr. from the German by Charles Salter. Source: Wellcome Collection.

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    underlying- water as possible. The aqueous residue is then evaporated in the beaker at ioo° C., and the whole of the remaining substance is placed in the desiccator and weighed, dried, cooled and re-weighed until the weight is constant or varies by not more than I m.grm. The loss in weight sus- tained by the fat—the weight of the beaker being known at the outset—gives the amount of water therein. The average amount of water in butter ranges from 13 of 15 per cent.; butters with a water content as low as 9 have been met with, while the maximum amount has been 20 per cent. Salt butters, especially those mixed with brine, gener- ally contain 18 per cent, of water. Of late butters blended with milk have been sold, these contain as much as 22 to 23 per cent, of water. 2. Estimation of Fat.—The residue in the beaker is loosened as well as possible from the bottom by means of a glass rod and washed with water-free ether on to the filter, which has been placed in a funnel in the mouth of the flask holding the bulk of the fat, the beaker and rod being rinsed and the filter and contents washed with ether until a test drop on a watch glass shows that all the fat is removed. The ether is then distilled off and the fat dried in the air oven at ioo° C., cooled in a desiccator and weighed when cold, the operations being continued until the weight is constant. The amount of fat ranges from 82*5 to 86'5 per cent. 3. Determination of Ash.—The residue collected on the filter and the filter itself are carbonised in a platinum cru- cible at a moderate heat and, after extracting several times with distilled water and filtering, calcined thoroughly. The filtrate is then poured by degrees into the ash in the cooled crucible and the whole dried in the water bath, incinerated with the used filter in the (covered) crucible, cooled and weighed, the weight of the two filters being deducted from the result. In the case of salted butter, only the total amount