‘Spartan’ apples were dipped in 4% CaCl2 solution after harvest. One week after treatment, the Ca concentration was 19 ppm higher at the 0–2.5 mm depth in the flesh of the dipped fruit. After 2 weeks, Ca was 41 ppm higher at the 0–2.5 mm depth and 26 ppm higher at the 2.5–5.0 mm depth. After 4 weeks, Ca was 36 ppm higher at the 2.5–5.0 mm depth, 25 ppm higher at the 2.5–5.0 mm depth and 16 ppm higher at the 5.0–7.5 mm depth. After 8 weeks, Ca was 68, 49, 43, 36, 30, 24, 27 and 27 ppm higher at 8 successive 2.5 mm depths. After 32 weeks, Ca was 84, 70, 62, 62, 61, 58, 62 and 62 ppm higher at the 8 successive depths in the dipped fruit.

The concentration of Ca in the flesh was closely related to the amount of breakdown in individual apples in 5 lots of ‘Spartan’ apple (Malus sylvestris Mill.) collected over 2 years. Correlation coefficients of 0.9 were obtained using log Ca and linear breakdown or log Ca and log breakdown. The amount of breakdown calculated for the 5 lots by the 2 equations was 100 percent at 70 ppm Ca, from 46 to 100 percent at 100 ppm Ca, from 3 to 12 percent at 150 ppm Ca and less than 2 percent at 200 ppm.

Fruits of ‘Spartan’ apple were dipped in solutions of commercial CaCl2 after harvest to increase their Ca concentration. Fruits were stored until the following June, then the flesh was analyzed for Ca. Undipped fruit contained 203 ppm Ca and fruit dipped in 4% CaCl2 (wt/vol) contained 278 ppm Ca, dry weight basis. When surfactants were added to the CaCl2 solution, the Ca concentration in dipped fruit was 230 to 250 ppm. When thickeners and surfactants were added, the Ca concentration in dipped fruit was 373 to 825 ppm. These results indicate that surfactants reduce the uptake of Ca by fruit from dips but thickners with surfactants increase it

‘Spartan’ apples from 29 orchards were dipped in 4% calcium chloride Solution at harvest Senescent breakdown was reduced from an average of 8.3% in the undipped fruit to 2.7% in the dipped fruit Firmness was increased by 0.38 kg (0.84 lb.) and Ca concentration in the fruit flesh by 76 ppm by the dip.