PROBLEM TO BE SOLVED: To provide a method of processing vegetable to produce frozen vegetable from chlorophyll-containing vegetable, which can suppress the deterioration of firmness, etc. caused by softening of vegetable tissue and also can suppress the discoloration and the deterioration of flavor upon preservation as the frozen vegetable even if the processing time of a blanching process is increased to deactivate an enzyme included in the vegetable.SOLUTION: The method of processing the chlorophyll-containing vegetable includes (A) a process for immersing the vegetable such as string beans in a ferulic acid-containing aqueous solution, (B) a process for immersing the vegetable obtained by the process (A) in a calcium-containing aqueous solution, (C) a process for blanching the vegetable obtained by the process (C), and (D) a process for freezing the vegetable obtained by the process (C) to obtain the frozen vegetable.
