36 



(6) It has beeu seen that the age of the tray does not greatly affect 

 the quantity of zinc which is contained in evaporated apples. 



(7) Experiments have shown that pure aluminium wire may be used 

 for making the netting on which the apples are dried, and it is probable 

 that perforated sheet aluminium may also be found useful for this pur- 

 pose. l>y the use of pure aluminium the presence of zinc could be 

 entirely excluded from the evaporated fruits, and thus all hygienic 

 objections to their use would fall. The presence of the minute amount 

 of alumina which would be introduced into the evaporated fruit would 

 be of no consequence, inasmuch as alumina is a natural constituent of 

 nearly all food products. Well-tinned iron wire would also make an 

 acceptable substitute for the wire covered with zinc now in use. 



(8) The manufacturers of evaporated apples in this country should 

 at once rigidly exclude all galvanized iron utensils from their factories 

 and substitute therefor drying trays composed of aluminium, tin, or 

 some other substance which will not permit ot any objectionable ingre- 

 dient entering the finished product. The use of bronze cutting instru- 

 ments should also be excluded and steel substituted. 



(9) The physiological eftects of the organic salts of zinc are not well 

 understood. The inorganic salts of zinc taken in large quantities act 

 as irritant poisons. Small quantities of zinc salts are constantly 

 administered in the practice of medicine, producing tonic and astrin- 

 gent effects. The continued use of small quantities of zinc for a long 

 period of time has not been known to produce any serious results. 

 Experience has shown that zinc is distinctly less poisonous than copper 

 or lead. 



(10) The normal quantity of zinc in the form of oxid found in Amer- 

 ican evaporated apples which have been dried on galvanized iron trays 

 is about 10 milligrams for every 100 grams of the fruit, or a little less 

 than 50 milligrams per pound. One grain, druggists' weight, is equiva- 

 lent to 65 milligrams. The quantity of zinc, therefore, in 1 pound of 

 evaporated apples dried on galvanized iron trays is only about two- 

 thirds of a grain. The quantity of zinc which would be taken by any 

 one person in an ordinary meal at which dried apples were served 

 would probably in no case ever exceed two-fifths of a grain. It is not 

 possible to regard this quantity as in any way prejudicial to health. 



(11) The continued use of bodies which are not distinctly poisonous, 

 but which are foreign to the natural constituents of the system, may 

 iinally produce derangement of health, and for this reason the manu- 

 facturers of evaporated fruits in this country should pursue such 

 processes as would exclude even the traces of zinc above mentioned. 



(12) American dried apples contain nearly one quarter of their weight 

 as water and ash, the mean percentage of water in the samples exam- 

 ined being nearly 24 and of ash nearly 1.25. The extreme variations in 

 moisture from the mean were found to be about 8 per cent. 



