Abstract:

This study aimed to study the effects of yeast mannan on postharvest storage of tomato fruit. Firmness, soluble
solid contents (SSC), color, ethylene release rate, respiration rate, β-galactosidase activity and wounded inoculation with
Alternaria alternata of tomato fruit infiltrated with different concentrations (0, 1.0, and 10.0 g/L) of yeast mannan were
investigated during storage. Results showed that yeast mannan could delay the decline of fruit firmness, retard the changes
of SSC, reduce the ethylene release and respiration rate, and delay the color change of tomato fruit during storage. Thereby,
the yeast mannan treatments delayed the progress of ripening and softening in tomato fruit and improved its storability.
The concentration of 1.0 g/L proved to be more effective. In addition, yeast mannan treatments inhibited the activity of
β-galactosidase in the fruit during storage and delayed the degradation of the cell wall. In the case of wounded inoculation
with Alternaria alternate, yeast mannan treatments could significantly inhibit the lesion area of the black rot on the fruit
caused by the pathogen and reduce the disease incidence during incubation.

Key words: tomato fruit, yeast mannan, storage quality, β-galactosidase, Alternaria alternata