62 specimens of deteriorated rice which were collected all over Korea, were classified according to their color outlooks, and the causitive microorganisms were isolated and identified.
The following results were observed;
1. 62 specimens of deteriorated rice were classified according to color outlooks into 7 types; reddish yellow, light reddish yellow, light gray yellow, light reddish yellow, light gray yellow, light red, ligt gray, dark gray and rice weevil type.
2. The isolated microorganisms from 62 specimens of deteriorated rice were 44 species, 5 genera of molds, 1 species of yeast, and 14 species, 4 genera of bacteria.
3. The frequently observed microorganisms which caused the deterioration were Asp. glaucus group, Asp. oryzae, Asp. candidus, and Asp. versicolor. Among bacteria, Bacillus was dominant.
4. The relationship between color outlook types and the deterioration causing microrrganisms was not definite, but Pen. islandicum from reddish yellow, Asp. candidus and Asp. clavatus from light reddish yellow, Asp. glaucus group, Asp. candidus, Asp. versicolor and Asp. fumigatus from light red, Asp. oryzae from light gray yellow, and Asp. glaucus group and Pencillium species from light gray and dark gray were chiefly isolated.
5. As mycotoxin producing fungi, Asp. fumigatus, Pen. citrinum, Pen. islandicum, Asp. flavus, and Asp. ochraceus were detected, but their growth frequencies were not very high to be problems except Pen, islandicum which infected an imported rice sample heavily.
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