not washed WB /■ o Yo nrrTuwrm J. 6 % 
28 BULLETIN 63, U. S. DEPARTMENT OF AGRICULTURE. 
wholly to those received in the commercial field-handling operations the decay was 
practically the same as in the case of lots where injuries were confined to those received 
in the washing and drying operations. From this the assumption may be drawn that 
the bad effects following washing are due not so much to actual injuries made in 
passing the fruit through the machine as to the inoculation of injured and bruised 
spots through the agency of dirty, infected water. There seems to be a definite 
relationship between the type of field handling and the occurrence of decay following 
washing. Injuries made in the grove, punctures from long stems, or other damage 
received as the oranges pass through the machinery are aggravated by the addition of 
moisture, especially when the water is not clean. On the other hand, the quality of 
work performed by the machinery is largely dependent upon the manner in which 
the fruit is handled in the grove, and this consideration emphasizes the necessity of 
careful and systematic methods, especially where washing must be employed. Fruit 
which is handled in groves and packing houses with sufficient care to insure its packing 
without injury usually shows much less decay after washing than the same or similar 
fruit which has been treated less carefully. 
Fruit which is covered with sooty mold must be thoroughly soaked before it is in 
proper condition for washing. This introduces a prolific source of infection — the 
soaking tank. Unless the water in the soaking tank is kept sanitary by being fre- 
quently changed, it soon becomes heavily charged with blue-mold spores, and is 
then one of the most dangerous features of the washing operations. As yet, no disinfect- 
ant has been found which 
CAREFUL COMMERCIAL 
p/ck and pack p/ck and pack proves effective against 
-"*» blue mold. Extensive in- 
vestigation of this phase of 
washed WEtHB&i-./v* HB^m^HH /a^ °/. the subject has shown the 
spores to be so resistant 
Fig lO.-Diagram illustrating the percentage of blue-mold decay ^ ^ d 
after holding oranges, washed and not washed, for two weeks m J 
a packing house; summary of all experiments, 1910-11. destroy them must be of 
sufficient strength to injure 
the surface of the fruit. The importance of maintaining the soaking tank in a sanitary 
condition is therefore fundamental. It should be emptied frequently, and sprays of 
fresh water should be directed against the fruit as it passes through the washing 
machine. 
RESULTS OF WASHING EXPERIMENTS. 
Tables IX, X, and XI, and figures 10, 11, and 12 show the results obtained during the 
season of 1910-11, when the washing experiments of the bureau were carried on in a 
comprehensive and systematic manner, giving the average percentages of decay found 
in carefully and commercially handled fruit, washed and not washed, respectively. 
The fruit was packed as if for shipment, but instead was held for two weeks in the 
packing houses and the percentages of decay determined by actual count. Table IX 
and its accompanying diagram (fig. 10) present a summary of all the washing experi- 
ments carried on during the season, including the work of 13 different types of ma- 
chines, operated in 32 packing houses. The figures show the relative increase in 
decay due to the washing operations alone in the case of the carefully handled fruit 
and to the combination of causes in the case of the commercially handled fruit. The 
carefully handled oranges, not washed, showed 1 per cent of decay after two weeks; 
the washed, 4.1 per cent. In the commercially handled lots, the fruit not washed 
showed 3.6 per cent of decay and the washed fruit 10.2 per cent. The figures 
include the results of work done in many different ways, and while they summarize 
the general effects of washing, some analysis of the data is necessary in order to bring 
out the points of fundamental importance. 
