REMOVAL OF '-SPRAY RESIDUE FROM APPLES AND PEARS 17 



punctures and cuts, to infections at the calyx following arsenical 

 injury, or to infections at the core following penetration of the clean- 

 ing solution. 



Anything which can be done on a commercial scale to reduce to 

 a minimum these chances for trouble will make for improved wash- 

 ing conditions and satisfactory results. 



CONCLUSIONS AND SUGGESTIONS 



The following conclusions and suggestions have been obtained 

 from the results of the experimental work as well as from practical 

 experience with the commercial operation of washing equipment 

 during the packing season. 



It is not safe to assume that any washing method will satisfac- 

 torily clean all fruit, regardless of its antecedent history, both as to 

 spraying practices and method of harvesting. There are limitations 

 to every cleaning method. The choice of materials for spraying as 

 weU as the manner of spraying the fruit in the orchard may materi- 

 ally modify the facility with which any method will remove spray 

 residue. In other words, the spraying practices should be chosen 

 with the purpose of making the cleaning of the fruit as easy as 

 possible. 



With proper operation of suitable equipment both apples and pears 

 can be satisfactorily cleaned without serious injury to the fruit. 

 Careless cleaning methods, hoAvever, may result in arsenical injury 

 at the calyx or stem, hydrochloric-acid burning, or chemical injury 

 at the core. Any of these injuries may open the way for storage rots. 



The sooner the fruit is cleaned after it is picked the more easily the 

 cleaning can be clone and the less risk of damage there is to the fruit. 

 In any event, fruit should be cleaned before it has passed the firm 

 stage of maturity. 



No matter what washing treatment is used, every precaution 

 should be taken to keep decayed fruit out of the cleaning equipment. 

 The sorting out of undesirable fruit generally requires additional 

 sorters at the dumping table and should not be left for the dumper 

 to attend to. 



Any washing method which applies the solvent solution to the 

 fruit by diffused spray, flood wash, flotation, or a combination of 

 these should give satisfactory results for ordinary cleaning require- 

 ments. This statement presupposes that all desirable precautions in 

 regard to proper washing have been taken. 



The ultimate choice of any of these machines by a fruit packer will 

 generally be influenced by such items as the initial cost of the equip- 

 ment and its capacity, the cost of operation per box of fruit, the 

 suitability for local requirements, the adaptability to the space avail- 

 able, and the general mechanical as well as cleaning efficiency of the 

 machine. 



Methods employing relatively deep submersion, especially when 

 the fruit is in constant turning motion and the exposure is prolonged, 

 should be avoided, especially with varieties frequently having open 

 calyx tubes. The latter include particularly Jonathan, Gravenstein, 

 Esopus Spitzenburg, Stayman Winesap, Ortley, White Pearmain, 

 and sometimes Delicious. The large-sized apples of any variety may 

 at times show this condition. 



