. Chemical testing of milk and cream . rt of condenser. The type of condenserknown as the globe condenser is very sat-isfactory for this purpose. Some ovensare constructed with a constant-level at-tachment. Balance.—Nice weighings are requiredin the determination of total solids in milk, and it is nec-essary to use the type of balance known as the analyticalbalance (fig. 26), the cream-test balance not being sensi-tive enough for this purpose. On the other hand, theanalytical balance can not be used with advantage inweighing cream charges. Both balances are required. Ananalytical balance sensi
. Chemical testing of milk and cream . rt of condenser. The type of condenserknown as the globe condenser is very sat-isfactory for this purpose. Some ovensare constructed with a constant-level at-tachment. Balance.—Nice weighings are requiredin the determination of total solids in milk, and it is nec-essary to use the type of balance known as the analyticalbalance (fig. 26), the cream-test balance not being sensi-tive enough for this purpose. On the other hand, theanalytical balance can not be used with advantage inweighing cream charges. Both balances are required. Ananalytical balance sensitive enough for the purpose can bepurchased for from $30 to $40. A set of accurate analyticalweights will also be required. Space does not permit di-rections for using the analytical balance. If the operatoris not familiar with its use, he is advised to consult someelementary treatise on quantitative chemical analysis. Itmust be borne in mind that the analytical balance is a verydelicate instrument and should be treated Fig. 24. — Jarwith per-forated coverfor use inemptying testbottles. 24 Desiccators.—Dishes that are warm can not be accuratelyweighed on the balance because air currents are createdwhich will buoy up the scale pan sufficiently to make theobject appear Lighter than it really is. Again, many sub-stances can not be exposed to the air without absorbingatmospheric moisture and in this way introducing an errorinto the weighing. For these reasons it is customaryalways to cool the dishes in a device known as a desiccator(fig. 27) before weighing them. A desiccator is a specially
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