In order to establish a rapid screening method for yeast and mold in food, the PCR-based QUALIBAXTM System (BAX Method) was compared to a conventional culture method using Potato Dextrose Agar (PDA Method) for detecting yeast and mold in margarine, filling and frozen dough. A spiked study on margarine used known strains of organisms often detected in the target food types: C. parapsilosis, C. sphaerospermum, P. aurantiogriseum, Mucor spp., A. versicolor and W. sebi. The correlation between 5-day results for the samples plated onto PDA and 48-hour results for the samples processed by the BAX Method was very high. Both methods demonstrated lower sensitivity for W. sebi. To improve the detection of W. sebi, the enrichment medium was modified by adding glycerol, glucose or sodium chloride to the broth. Results showed improved sensitivity rates for W. sebi when glycerol or glucose was added. An additional study compared the BAX Method with standard enrichment to the PDA Method on 110 unspiked samples: 75 were naturally contaminated and 35 were artificially contaminated through exposure to highly contaminated environments. Both methods demonstrated the same high levels of sensitivity in detecting yeast and mold. These studies suggest that the BAX Method can be used by food processors for rapid and highly sensitive screening when investigating yeast and mold contamination.

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手指衛生管理において，消毒が適正であるかどうかは非常に重要な事項である．本研究では，手洗い時のエタノール消毒効果をより確実に発現させる条件はいかなるものかを中心に検討した．石けんで手洗いを行い，ペーパータオルで水分をふき取った後には手洗い前に比べて手指の細菌数は減少したが，除菌効果は十分とはいえなかった．これにつづいてエタノール消毒(両手掌に噴霧し，擦り合わせながら乾燥)をした場合，80%, 99.5% エタノールでは十分な消毒効果がみられたが，70% では効果が発現しなかった．一方，手洗い後に手指を十分に風乾してエタノール消毒をすると，いずれの濃度でも十分な効果が認められた．そして，これらの条件での手洗い前後の手指水分量を調べてみると，手洗い後にペーパータオルでふき取った場合，手洗い前よりも水分量が依然として高かったのに対し，十分に風乾した場合，手洗い前とほぼ同等になった．以上から，エタノールによる手指消毒では手指を十分乾燥させることが極めて重要で，使用するエタノール濃度は 80% 以上が望ましい．

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