Terminology:
Fruit firmness (P) refers to the ratio of fruit unit area (S) to the pressure (N) of the pressure spring under test.
P=N/S
PδΈFruit hardness (10^5 Pa or kg/cmΒ²)
NδΈForce exerted by a force-measuring spring on the fruit surface(N or kg)
SδΈ Fruit area of thrust surface (cmΒ²)
