GLOBULIN. ALBUMINATES. 133 



then extracted with 10 P- C - chloride of sodium for 24 to 48 hours in 

 a cool place, is strained through muslin, and a second time through 

 a plug of tow placed at the bottom of a funnel. 



A globulin may be obtained by the same method from pea meal, 

 but the reactions are not so pronounced. 



1. The solution of rayosin is slightly opalescent. 



2. Perform the reactions for proteids and note carefully any 



difference in the reactions where any occur. 



3. Saturate 7 cc of the solution in a tube with MgSO 4 , filter 



into another tube and test the nitrate for the presence 

 of a coagulable proteid, by acidification and boiling, 

 there will probably be none. 



4. Pour some of the solution by drops into a tube nearly full 



of water. A cloud will form in the track of each. 

 Explain how this occurs. 



Albuminates or Derived albumins. 



Alkali albumin. Form alkali albumin by adding drops of caustic 

 alkali solution (NaOH or KOH) to 5 cm of pure egg white in a tube. 

 The previously fluid albumin will soon turn into a clear jelly, adhering 

 to the tube when inverted. Fill the tube with water and stir up the 

 jelly with a glass rod until most of it is dissolved. 



1. Alkali albumin is soluble in a weak alkali but is 



precipitated on neutralisation. Add litmus solution to 

 a distinct tint and neutralise with dilute acetic acid. 

 The fluid becomes turbid. On the further addition of 

 acid the turbidity disappears. It reappears on neutrali- 

 sation. 



2. Boil some of the solution, it does not coagulate. 



3. Sulphur is liberated in the formation of alkali albumin. 



To 2 cm egg white add 3 volumes NaOH solution. Mix 



