24 



THE SALTING OF FISH. 



Table 2. — Retardation of Penetration of Salt into Fish " Due to 1 Per Cent 

 OF Magnesium Chloride Impurity, Expressed in Per Cent of Chlorine in 

 Dry Sample, at 68° F. 



a Inner section of fish, J to 1 cm. 



In this case, also, the chlorine content of the inner sections of fish 

 salte'd with pure salt is higher than that of similar sections of fish 

 salted with the salt containing 1 per cent of magnesium chloride. 



Table 3 shows that an increase in the amount of magnesium chlo- 

 ride to 4.7 per cent caused a further retardation. 



Table 3. — Retardation of Penetration of Salt into Fish Due to 4.7 Per 

 Cent of Magnesium Chloride Impurity, Expressed in Pek Cent of Chlorine 

 IN Dry Sample, at 68° F. 



Table 4 shows that the presence of the sulphate ion in solution 

 caused a greater retardation than the consequent lowering of the con- 

 centration of the chlorine ion should cause. 



Table 4. — Retardation of Penetration of Salt into Fish " Due to 10 Per 

 Cent of Sodium Sulphate Impurity, Expressed in Per Cent of Chlorine in 

 Dry Sample, at 68° F. 



a loner section of fish, i to 1 cm. 



Further than a retardation of the rate of penetration of the sodium 

 chloride, calcium chloride and magnesium chloride had noticeable 

 effects on the physical appearance of the salted fish. Both the cal- 

 cium chloride and magnesium chloride as impurities in salt made a 

 much harder fish than pure sodium chloride. Calcium chloride, ap- 

 parently, was most active in this regard. Pure sodium chloride, 

 when used dry for salting fish, produces a soft, yellow-meated fish 

 which will bend when held in the hand. Five per cent of calcium 



