10 BULLETIN 569, U. S. DEPARTMENT OF AGRICULTURE. 



are carried out they pass under water sprays which give them a final 

 rinsing. 



(/) The air-blast or geyser washer works on the same general 

 principle as the preceding type, but produces the agitation by blasts 

 of air entering the tank at or near the bottom. 



(g) In the cascade washer the tomatoes are carried up a tight- 

 bottomed conveyor inclined at an angle of 30° to 50°. Near the 

 top are the inlets for water which emit a sufficient amount to produce 

 a vigorous flow down over the ascending stream of tomatoes. Al- 

 though it is a good rinser, it is not sufficient alone to remove 

 thoroughly the sticky soil from the fruit. 



SORTING. 



ITS IMPORTANCE. 



A careful consideration of the causes of failure in making clean, 

 sound, sanitary tomato products shows clearly that more difficulty is 

 experienced in effecting satisfactory washing, prompt handling, and 

 efficient sorting than in any of the other phases of the manufactur- 

 ing process. Sorting is the most important of these operations, in 

 which the judgment of the workman plays a considerable part. 

 Satisfactory washing is largely a question of proper operation of a 

 mechanical device. This may be said also of many of the other 

 operations about the factory, but so far no mechanical contrivance 

 for separating the decayed from the good parts of the tomatoes has 

 been placed upon the market. This operation must still be performed 

 principally by hand. Although some washers, if properly con- 

 structed and operated, will assist in removing the badly soft-rotted 

 tomatoes, efficient hand sorting must be employed if a uniformly 

 good, sound product is to be obtained. 



Experience has shown that in factories where the tomatoes are 

 used only for peeling stock and where all the trimmings are thrown 

 away sorting is an unnecessary expense. In the making of pulp of 

 any kind, however, efficient sorting is absolutely necessary. Other- 

 wise there can be no assurance of producing a uniformly sound 

 product with low counts of microorganisms. 



The conditions observed and the results obtained in various fac- 

 tories show that there is little, if any, choice between sorting the 

 tomatoes before and after washing. Some of the best, as well as some 

 of the poorest, results were obtained in factories where one or the 

 other of these methods was employed. Approximately two-thirds 

 of the plants visited during the seasons of 1915 and 1916 that did 

 any sorting at all were using the wet method, and one-third the dry 

 method. In order to remove clinging pieces of partially decayed 

 tomatoes, the tomatoes always should be subjected to a washing or 



