- Flesh firmness and background skin colour are generally accepted as reliable methods to determine maturity.
- Start monitoring the fruit in the orchard at least one week prior to the expected harvest date as the correlation between flesh firmness and skin colour may vary from orchard to orchard and year to year.
- Fruit sampling should be throughout the orchard in a W-fashion.
- Fruit should be sampled in the top, middle and bottom of the tree as well as on the inside and outside of the trees. It is important to sample from different positions within the tree, and the fruit from different positions should be kept separate to enable determination of the ripening pattern within the tree and the orchard.
- Maturity samples must be taken at the same time of the day, preferably in the mornings, to ensure accurate flesh firmness readings.
- Remove a thin slice of peel from opposite sides on the centre of the cheek of each fruit.
- Hold the fruit firmly in one hand and rest your hand on a rigid surface.
- Zero the penetrometer and place the plunger head of 11 mm in diameter on the spot where the skin was removed.
- Apply steady downward pressure on the penetrometer until the plunger has penetrated the flesh of the plum up to the depth mark of the plunger.
- Remove the plunger and note the reading on the penetrometer, to one decimal.
- Repeat the process on the opposite side of the same fruit after zeroing the penetrometer.
- Determine the average of the two firmness readings for each fruit.
Peach
PE1 - Flesh Firmness