CHAPTER XIV. 

 EXAMINATION OF ADIPOSE TISSUE. 



I. Separation of Fat and Connective Tissue. 

 II. Decomposition of Fat into Fatty Acids and Glycerin. 



I. SEPARATION OF FAT AND CONNECTIVE TISSUE. 



Cut into fine pieces with a knife or a pair of shears 10 g. 

 of adipose tissue, 1 grind as finely as possible in a mortar, 

 place in a flask, and heat to boiling on a water-bath with 

 40 cc. of absolute alcohol. The fat dissolves, leaving the 

 connective tissue behind. Filter, wash, first with alcohol, 

 then once or twice with ether, press the residue on the filter 

 between filter-paper, and allow the ether still adhering to 

 evaporate by letting it lie in the air: fibrous mass consisting 

 of fat-cells and connective tissue. Show the presence of albu- 

 min in the residue by heating with nitric acid and then add- 

 ing sodium hydroxide solution (xanthoproteic reaction), and 

 also by boiling some of the substance with water and adding 

 a few drops of Millon's reagent. The conversion of the con- 

 nective tissue into gelatin cannot be brought about by simply 

 boiling with water as in the case of ossein. A higher tem- 

 perature (boiling under pressure) or very long-continued boil- 

 ing is required to accomplish this. 



1 Preferably unsmoked hog-fat. 



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