OCR Text |
Show Use Of Microscope in Unique Test Tho United States bureau or chomlBtry has round that tho mlcroscopo may bo used to excellent excel-lent advantage In tho oxamlnntlon of food and drug products for tho discovery of adultorants. This Is a now Idea nnd a largo amount of work hus been done In the application of tho mlcroscopo mlcro-scopo to annlytlcal work, but thoro aro cortaln cor-taln parts of tho Held as yet untouched. Microscopic Mi-croscopic tests havo bocomo an Important adjunct ad-junct to tho tcat-tubo nnd blast-lamp methods of annlytlcal work. As an esumplo ot tho uso of tho microscope, n enso recently brought to tho nttcnllon ot tho bureau or chemistry was a sample or celery seed adulterated with nearly 40 per cent, of powdered rock. This adulteration wns of such a character as would easily escape tho notice or tho ordinary buyer. Tho usefulness of tho simple magulfler In examining rood nnd drug materials, howover, Is limited and rccourso must bo had to tho compound mlcroscopo tor tho examination ot the piodu'ctB which aro mado up or small articles. Commercial starches can bo identified with consldorablo accuracy by means of the mlcroscopo. ml-croscopo. Tho examination of spIceB forms another an-other Interesting application of this method of rood analysis. In coffee nnd chocolnto preparations prep-arations roasted chicory, coreals, and peas In tho caso of tho former and starchy materials and cocoa shells In tho caso of tho latter, can bo detected by means or tho microscope. Thickeners used In tho production of artificial ar-tificial Jollies, Jams, and other confections, can bo moro or less easily detected by microscopic tests. Tho thickener materials nro gelatin, starch, agar-agar, gum tragacanth and gum arable. Another example of microscopic examination ex-amination Is tho detection of flowers of which honey Is mado. This Is of practical value In tho annlysls of honoys purporting to bo from certain flowers. A detailed description of how tho mlcroscopo comes to the aid of tho chemist when ho endeavors to dotqet fraud In food and food products Is given In tho year book of the department of agriculture |