Pressure Tester of Fruit Maturity 7 



the softening of the fruit and that the tests with the skin intact 

 portray the actual condition of the flesh much less accurately than 

 those with the skin removed. 



Table 1. — Comparison of testing, with and without peel removal, the maturity 



of apples 





Test of pressure applied to fruit (poimds) 



Variety 



At time of picking 



When in prime eating 

 condition 





Peel 

 removed 



Peel not 

 removed 



Differ- 

 ence 



Peel 

 removed 



Peel not 

 removed 



Differ- 

 ence 



Mcintosh 



13.5 

 17.9 

 15.8 

 16.2 

 17.4 

 18.0 

 18.1 

 19.0 

 20.1 

 19.9 

 23.0 



18.2 

 19.5 

 18.3 

 19.4 

 20.5 

 19.3 



4.7 

 1.6 

 2.5 

 3.2 

 3.1 

 1.3 



8.1 

 9.3 

 9.9 

 9.8 

 11.2 

 10.4 

 9.8 

 11.6 

 10.1 

 »15.8 

 12.8 



12.8 

 11.8 

 16.7 

 18.1 

 16.9 

 13.3 

 16.5 

 17.5 

 18.6 

 27.6 

 21.0 



4.7 



Grimes Golden - 



2.5 



Delicious .. 



6.8 



Stayman Winesap 



8.3 



Rome Beauty 



5.7 



"Kirig David _ . _ 



2.9 



Baldwin 



19.2 1.1 

 22.2 3.2 

 24.4 4.3 

 28.8 ; 8.9 

 27.2 ; 4.2 



6.7 



Ben Davis 



5.9 



Winesap .. 



8.5 



Yellow Newtown.- 



11.8 



Ai^asisas (Mammoth Black Twig) 



8.2 











» Not quite prime eating condition. 



INFLUENCE OF RATE OF APPLICATION OF PRESSURE ON 

 PRESSURE-TEST RESULTS 



It is realized that in the hands of various individuals the rate 

 of application of pressure in testing fruit will vary somewhat. To 

 determine what the effect of this would be upon the readings, a 

 series of tests was made in which the pressure was applied so rapidly 

 that it was impossible to read the scale with entire accuracy. On 

 the same apples another series of tests was made in which the pres- 

 sure was applied very slowly. The results of these tests are reported 

 in Table 2. 



Table 2.- 



-Influence of sloiv and rapid application of pressure on results secured 

 with the tester in determining the firmness of apples 



Variety 



Pressure in pounds 



«S^ siowtest wa- 



Winesap. 16.0 15.8 0.2 



Stajrman Winesap .. ... ... 12.1 11.6 .5 



Ben Davis 13.9 13.3 .6 



It is apparent that there is some difference due to the rate of appli- 

 cation of the pressure. Ben Davis showed the greatest difference 

 (six-tenths of a pound) as the average on a lot of 25 apples. Since 

 these figures represent the greatest possible extremes, the rate of 

 application of the pressure is apparently a less important factor 

 than might be supposed. So long as the pressure is applied at a rate 

 sufficiently slow to be read accurately little variation due to this 

 cause will be found. 



