Cereal Chem 55:332 - 340.  |  VIEW ARTICLE
Microbiological Study of Exported Soybeans.

C. W. Hesseltine, R. F. Rogers, and R. J. Bothast. Copyright 1978 by the American Association of Cereal Chemists, Inc. 

An overseas shipment of bulk soybeans was studied microbiologically both before and after shipment. Samples were collected at four levels (0-3, 3-6, 6-9, 9-12 ft) in three holds of the ship. Each sample was analyzed microbiologically as the original sample, as whole intact beans, and as splits. Bacterial counts on the surface of intact beans did not change generally during shipment. Counts per gram of splits or damaged beans, however, increased from 6,400 to 170,000 before shipment to 36,000 to 2,100,000 after shipment. Fungal counts were generally higher on yeast extract agar than on Czapek's agar. No apparent increase in fungi on sound beans was observed; counts were much higher on the splits, ranging from 17 to 13,000 per gram, but did not increase after shipment. A small but rather uniform actinomycetous flora was found. A variety of fungi was encountered, the two most common forms on the surfaces of the beans were members of the Aspergillus glaucus group and species of penicillium. Soybean germination was reduced during shipment except for those held at the lower level. Contamination of the beans by fungi increased markedly at the top three levels but not at the lowest level. The splits from all lots were heavily contaminated (66- 98%), and the infection rate went up during shipment at all levels except the lowest. The fungi isolated from the soybeans were represented by many genera, with A. glaucus and Penicillium species being the ones most often encountered. A. glaucus infected whole beans, and splits were about equal. Penicillium species occurred three times more often in splits than in whole beans.