Development and Application of Medium for Tobacco Mold Counting Test

In order to develop a medium suitable for testing the amount of mold, eight molds common in tobacco and tobacco products were chosen (including Aspergillus flavus, A. niger ATCC16404, A. restrictus CGMCC 3.3973, Penicillium citrinum, P. chrysogenum, Mucor racemosus CGMCC 3.206, Rhizopus stolonifer CGMCC 3.2045 and Trichoderma viride), five common mold media (Rose Bengal agar, Czapek agar, High salt Czapek agar, hypertonic Czapek agar containing 20% sucrose, and Potato dextrose agar) and four pilot media were tested via primary and secondary screening. The results showed that comparing with other media, the improved medium, potato dextrose agar No. 1 (potato 200 g, glucose 20.0 g, NaCl 30.0 g, agar 16.0 g, chloramphenicol 0.1 g and distilled water 1000 mL), was more suitable for tobacco mold counting test due to its coverage of microflora and accurate counting results.