The gene expression and regulation associated with the initial stage of rind peeling of the satsuma mandarin (Citrus unshiu cv. 'Miyagawa-wase') was characterized through the generation of 626 expressed sequence tags (ESTs) derived from a cDNA library prepared from albedo tissues collected 60 days after anthesis. A Total of 451 ESTs was found to have significant similarity to the known sequences. Using our inhouse database, a catalogue of 222 ESTs annotated with their putative functions was prepared and compared to the previously prepared catalogue of 442 ESTs derived from mature albedo tissues. In consequence, gene homologues associated with cell wall events were preferably found in this library.