Determining Firmness of Test Apples 



Firmness of the test apples was deter- 

 mined by a Magness -Taylor pressure gauge 

 (fig. 8). With this device, a plunger with 

 a diameter of 7/16-inch was inserted into 

 the flesh of an apple where the peel had 

 first been removed. The resistence of the 

 apple, measured in pounds, registered on a 

 scale in the handle of the tester. The 

 harder the fruit, the greater its resistence, 

 and the more pounds it registered on the firm- 

 ness scale. Firmness of the fruit was prob- 

 ably the most important single factor in 

 determining the amount and severity of bruis- 

 ing that an apple incurred in the packing 

 operation. The evidence indicates a firmness 

 index--around 10 or 11 pounds--below which 

 apples cannot safely be handled mechanically. 

 In fact, it is questionable if such soft 

 apples can be safely handled by any means. 



Criteria for Evaluating Bruise Damage 



Bruises were classified as either slight, 

 moderate, or severe. This permitted the 

 extent of each bruise as well as the number 

 of bruises to be tabulated. A definition 

 of each bruise classification as used in 

 this study appears below: 



BN-7506 



Figure 7. --Test fruit was 

 selected by careful exami- 

 nation of each apple to 

 assure that it was free of 

 bruise. 



Slight Bruising - (Applies to U. S. Extra-Fancy Grade) 



a. Bruises of slight depth with a single bruise exceeding 

 1/2" in diameter or an aggregate area of bruises exceeding 

 3/4" in diameter. 



b. Bruises of lesser area more than slight depth or soft. 

 (Slight depth means not over 1/8") 



Moderate Bruising - (Applies to U. S. Fancy and U. S. No. 1 Grades) 



a. Bruises of moderate depth with a single bruise exceeding 

 3/4" in diameter or an aggregate area of bruises exceeding 

 1" in diameter. 



b. Bruises of lesser area more than moderate depth or soft. 

 (Moderate depth means not over 1/4") 



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