XIV. CANNED VEGETABLES. 



1 PHYSICAL EXAMINATIONS-TENTATIVE. 



Note carefully the external appearance of the packages to detect the presence of 

 "leakers", "swells" or "springers". In general the ends of sound tins of canned 

 vegetables are slightly concave. On opening the package note the relative pro- 

 portion of solid and liquid contents and the level of the solids and of the total con- 

 tents in the tin. Note the general appearance, odor, flavor, color and size of the 

 vegetables; appearance of the liquor or brine, whether clear or turbid, and the con- 

 dition of the inner walls of the container, especially as to blackening and corrosion. 

 In all instances the analyst should familiarize himself with the normal appearance, 

 odor, color, flavor and other properties of the product under examination. Care- 

 ful macroscopic or microscopic examination should be made for worm infestation, 

 mold, dirt, or other evidence of decomposition or filth. 



2 PREPARATION OF SAMPLE.— TENTATIVE. 



The preparation of the sample for analysis depends upon the character of the 

 product and the determinations to be made. Samples in which only the solid or 

 liquid portion is required should be treated as follows: Weigh the full can, open, 

 pour off the liquid, allow the solid portion to drain for a minute, re-weigh the can 

 and drained vegetables, then remove the solid portion and weigh the dry, empty 

 can. The method selected for draining the vegetables is dependent upon the nature 

 and condition of the sample. In most cases it is sufficient to cut around the cover 

 and before turning it back allow the liquor to drain through the slit. Whenever a 

 portion of the solid material would escape with the liquor by this procedure, drain 

 upon a piece of cheese-cloth. From the weights thus obtained determine the per- 

 centage of liquid and solid contents. If only the solid portion is required, separate 

 in a similar manner and grind thoroughly the drained vegetables in a mortar or 

 food chopper. If a composite of the solid and liquid portion is required, grind 

 thoroughly the contents of the can in a mortar or food chopper. In all cases mix 

 thoroughly the portion used and preserve the balance in glass-stoppered containers. 

 Unless the analysis is to be completed in a reasonably short time, determine the 

 moisture in a portion of the sample prepared as above and, in order to prevent decom- 

 position, dry the remainder and then expose to air until it becomes air-dry, grind, mix 

 thoroughly and preserve in glass-stoppered containers. A second moisture determi- 

 nation is required in this procedure. 



3 MOISTURE.-TENTATTVE. 



Dry a quantity of the sample, representing about 2 grams of dry material, as 

 directed in EX, 2. 



4 ASH.-OFFICIAL, 



Determine total ash as directed in VIII, 4. 



5 SALT.-OFFICIAL. 



Determine chlorin as directed under HI, 1 5, and express the result in terms of 

 sodium chlorid. 



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