CANNED VEGETABLES. bo 



Precipitate lend with potassium ehromate in an acetic acid solution; and 

 weigh upon a tared filter as lead chromate. 



Evaporate the filtrate from the hydrogen sulphid precipitate to about 60 cc; 

 add bromiii water to oxidize the iron salts and any remaining hydrogen sulphid. 

 Boil off the excess of bromin and, unless the solution is distinctly yellow, add 



few drops of concentrated solution of ferric chlorid to make it so. Nearly 

 neutralize the mineral acid with ammonium hydroxid, and add ammonium 

 acetate to precipitate iron phosphate and excess of iron. Filter and thoroughly 

 wash the precipitate. To the filtrate, made distinctly acid with acetic acid and 

 boiled, add hydrogen sulphid to precipitate zinc. Unless the zinc sulphid comes 

 down white, it should be dissolved, again treated with ammonium acetate to 

 remove traces of iron, and reprecipitated as sulphid. Finally collect the zinc 

 sulphid upon an ashless filter, ignite, and weigh as zinc oxid. 



8. Soaked Vegetables. 



A class of canned vegetables commercially known as "soaked." goods is 

 frequently found upon the market and constitutes the cheapest grade of vege- 

 tables sold. Peas, beans, and corn, or combinations of these three, are most 

 often found in this class. The materials used for " soaked " products are the 

 ordinary matured peas and beans, such as are used for seed or are sold dried 

 upon the market, and corn that has passed the stage at which it can be supplied 

 for the green market. 



The composition of soaked vegetables probably varies but little from that of 

 the younger products, yet they do not possess an equal value as a relish. In 

 the mature vegetables the percentage of total solids is much higher than in the 

 young and more succulent vegetables, and this condition holds true in the 

 canned goods if only the solid contents of the can are considered. 



Soaked peas and beans have the general appearance of the well-matured 

 product. The cotyledons are well formed, firm, and mealy. With the pea the 

 caulicle is particularly prominent, the process of soaking having started its 

 development. In the case of corn, the kernel is plump and hard and less milky 

 than the younger kernels. The succulence so characteristic of the green pea, 

 bean, and corn is entirely lacking. From their nature it is difficult to apply 

 specific tests to this class of goods, but a little practice will enable the analyst 

 to detect them with reasonable certainty by inspection of their appearance and 

 by the sense of taste. 



