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



times serve as a quick, rough method of arriving at a knowledge of 

 the character of the stock. 



The data obtained show that on unsorted stock the percentage by 

 number of tomatoes with rotten spots is approximately six times 

 as great as the percentage by weight of decayed material. In seek- 

 ing to estimate the proportion of decay in this manner, however, in 

 the practical testing of stock the results can be regarded only as a 

 rough approximation, since the variation in individual cases is very 

 wide, ranging from a ratio of about 2 in some cases to 15, and in a 

 few instances even higher than this. If this method is to be used in 

 a practical way it should be used only where the percentage by num- 

 ber of decayed tomatoes does not exceed about 15, since even in that 

 event it would indicate very roughly 2^ per cent of rot by weight. 

 The factor, as a rule, becomes smaller as the percentages increase, 

 i) wing to the relatively higher proportion of tomatoes with large - 

 spots. In the samples of sorted stock the average ratio of percentage 

 of spotted tomatoes by number to percentage of rot by weight was 

 about 10 to 1. 



These relationships indicate that the rotten or spotted condition 

 in unsorted stock averaged one-sixth of the mass of the tomato in 

 which found, while in the sorted stock it averaged about one-tenth 

 of the mass. 



COST OF SORTING. 



The question of the cost of sorting is important to the manufac- 

 turer. The wage commonly paid for this type of labor is about 15 

 cents per hour. The output by the table system of sorting ranges 

 from 5 to 8 bushels per sorter-hour. Hence, the minimum cost by 

 this system is about 2 to 3 cents per bushel. The investment for 

 sorting equipment in this system is practically nothing. 



By the apron system, good effective sorting can be made at the 

 rate of 20 bushels per sorter-hour, thus reducing the labor cost to 

 about three-fourths of a cent per bushel. This is simply for the 

 removal of the tomatoes that are more or less decayed and that must 

 be trimmed if any part is to be retained for use. The trimming 

 process itself is believed to be usually a self-paying proposition. 



TRIMMING. 



Some packers have been observed to discard the whole of any 

 tomato that showed a decayed spot. Tests made under factory con- 

 ditions, however, prove that this is a wasteful practice, since the 

 average amount of decay on unsorted stock is only about one-sixth 

 of the whole tomato. Hence, to remove absolutely all traces of decay 

 from each tomato, usually less than one-third of the tomato would 

 need to be cut out. The remainder of the tomato would be entirely 



