Bacterial Contamination of Carrots and Edible Burdock Using “Takikomi Gohan”

Abstract

  Carrots and edible burdock are frequently used when making “takikomi gohan”. Bacteria populations such as standard plate counts, coliform bacteria counts, Escherichia coli counts and Bacillus spp. counts in carrot and edible burdock samples were examined. No E. coli was isolated from all samples in this study. Indicator organisms as standard plate counts of the “washing-peel” carrot samples, and the “washing-peel-washing” edible burdock samples were low. After heat treatment (98℃ for 20 min) of the “washing-peel” carrot and all processed edible burdock samples, standard plate counts were also low. Coliform bacteria counts and Bacillus spp. counts in samples before and after processing had no statistical difference. Enterotoxin-positive B. cereus was isolated from the “washing-not peel” carrot sample. Our study suggests that washing and peeling of carrots, and washing, peeling and washing of edible burdock, followed by heating, are effective to reduce standard plate count bacteria contamination. B. cereus is a spore forming bacteria. B. cereus on carrots and edible burdock is a food poisoning risk in “takikomi gohan”.