326 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



The work was planned along lines similar to those followed in the 

 earlier investigations, which included a determination of the percent- 

 ages of mechanical injuries made in preparing the fruit for ship- 

 ment, together Avith a study of the relation of these injuries to blue- 

 mold decay and the effect of various packing-house handling methods 

 (washing, brushing, and packing without any special cleaning treat- 

 ment), all furnishing data for a comparison of the behavior of fruit 

 very carefully handled by the bureau investigators with fruit from 

 the same groves picked and handled under ordinary commercial con- 

 ditions. 



A very large increase in the percentage of mechanically injured 

 fruit in packing houses and groves which previously had been doing 

 exceptionally good work indicated a serious letting down in the 

 standard of handling. The average percentages of injury in the 

 different houses and groves examined ranged frorn 4.8 to as high as 

 53.6 per cent. The injuries made by individual pickers ran as high 

 as 85 per cent. Most of the injuries consisted of clipper cuts, but 

 abrasions of various kinds, gravel punctures, scratches, etc., were 

 present in large numbers. 



Handling and packing experiments designed to give a direct coni- 

 parison of fruit very carefully handled with the same type of fruit 

 handled under ordinary commercial conditions, carried on in 25 dif- 

 ferent packing houses and including 49 experimental series of fruit, 

 showed a very definite relation to exist between the type of handling 

 given the fruit and the occurrence of the decay. Though the condi- 

 tions for handling and marketing were very unfavorable, the fruit 

 carefully picked and handled by the bureau investigators averaged 

 less than 2.8 per cent of decay after being held for two weeks, while 

 fruit from the same groves given the ordinary commercial treatment 

 showed 14.9 per cent after the same length of time. The work 

 showed conclusively that brushing and washing very materially 

 increased the decay losses. 



The work of the present season corroborates the results of the 

 earlier bureau investigations in every respect and indicates that the 

 proper solution of the decay difficulty rests mainly with the packing- 

 house management. 



Precooling INVESTIGATIONS. — At Lodi, Cal., 12 full carloads of 

 grapes were precooled and a number of special experiments with 

 smaller lots were run in connection with the handling and shipping 

 investigations in September and October, 1910. An average reduc- 

 tion of 22.05° F. in the temperature of the fruit in the cars was 

 accomplished, after an average of 7 hours and 22 minutes, by forcing 

 about 6,000 cubic feet of air per minute through the cars at tem- 

 peratures ranging from 26° to 37° F. In the two seasons during 

 which the precooling investigations of grapes were carried on the 

 results of the work are rather indeterminate so far as the effect on 

 the occurrence of decay in transit and on the market is concerned. 

 No marked reductions in decay have resulted from the precooling 

 treatment, and in some instances negative results were obtained. 

 The indications are that some problems connected with the rapid 

 reduction of the temperature of this very perishable fruit after 

 loading in cars are not yet fully understood. 



