Effect of Drying Methods of Rice Flour on Growth Properties of Bacillus cereus and Enterobacter sakazakii

쌀가루의 건조방법에 따른 Bacillus cereus와 Enterobacter sakazakii 생육 억제 특성

  • Published : 2007.06.30

Abstract

In order to sterilize Bacillus cereus and Enterobacter sakazakii in rice flour, hot-air drying ($65^{\circ}C$/15 min, HT) and microwave drying (700 watt/30 sec, MT) treatments were evaluated and a storage study performed. Color changes (${\Delta}E$) appeared to be less in the MT rice flour than in HT treated rice flour. The effectiveness of the MT treatment showed reduced growth rates for B. cereus (0.54 log CFU/g) and E. sakazakii (1.45 log CFU/g). The populations of B. cereus in the control (NT) rice flour greatly increased during storage at 4, 10 and $20^{\circ}C$ as storage times increased. However, the growth of B. cereus was minimized in the MT rice flour. In conclusion, MT treatment is considered to be a good drying method when substituted for HT treatment to assure microbial safety in rice flour.

Keywords

Bacillus cereus;Enterobacter sakazakii;rice flour;microwave

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