Morphological and Physio-chemical Characterization of Dyospiros digina (Black Sapote) at the Subtropical Horticulture Research Station in Miami, Florida

The black sapote is a globe-shaped berry, with a persistent calyx with a diameter of 7 to 12 cm; the skin is bright green at physiological ripeness and is adhered to the pulp; the pulp is brown to black, very abundant and sweet, containing 6 to 10 seeds per fruit .

Fruit of several black sapote trees were evaluated and characterized at the Subtropical horticulture Research Station in Miami, Florida.

Thirty fruits were harvested from accessions  in 2012 and allowed to ripen at room temperature.

Parameters measured were fruit and seed length, diameter, and weight and number of seeds; color and Brix, pH, and acidity.

Maturation time ranged from 4-7.  The mean fruit weight for  large fruits was 358.39 g; 250.0 for medium size and 140.0 grams for the small. The medium size fruit showed the highest weight loss of 6.67 g, followed by the small size fruit with 4.98 grams, large fruits showed an average of 3.42 % weight loss.

 Mean fruit length and diameter was significantly lower for ‘the small fruits with 67.10 and 68.3 mm respectively.

Brix content for large, and medium fruits was 20.36, 17.33 ^OBrix respectively. The smaller fruits showed the lowest 16.53 ^OBrix. The medium size fruits had an average of 7.22 seeds per fruit significantly higher than all but the large (5.22). Seed weight, length and width were the smaller on the large fruits (10.99 g; 22.1 mm, and 14.45 mm) followed by the medium size (14.66 g; 20.66 mm; and 14.0 mm). The small size fruits (14.33 g; and 11.2 mm).

Citric, tartaric and malic acid content was the highest in the small fruits (0.33; 0.38; and 0.35) followed by the medium size fruits (0.32; 0.37; and 0.34) and the lowest in the large fruits (0.31; 0.36; and 0.32).

Fresh dry weight ratio loss was the highest in the small fruits with 28.0%, followed by the large fruits 25.0% and the lowest in the medium size fruits (22%).

 Color of the ripe and unripe fruit skin was L=63.44; a*=-10.29; b*=28.19; C= 30.54 and h= 110, L=51.27; a*=-3.31; b*=12.26; C= 12.65 and h= 104 respectively. Whereas the color of the seeds was L=39.44; a*=13.70; b*=12.63; C= 17.23 and h= 20.70

The ripened flesh of most fruits was considerably moist, very sweet, and had good flavor.

This research could further assist users in improving their production and handling through their breeding and advertising programs.