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Bean sprouts (Bønnespirer)
Bean sprouts Bean sprouts
The product is examined within 2 hours after purchase.

The product is manufactured in close contact with drinking water and the flora is thus characterized of both the water content of the bacteria and the bacteria that has survived on seeds and propagation of these. The typical flora is a gram-negative mixture flora. This consists of pektinolytiske species Pseudomonas, Pantoea (Erwinia) and Xanthomonas. The latter two are yellow pigmented and Pseudomonas fluorescence produces a water-soluble yellow-green pigment.		 Phase contrast microscopy of a 10-1 dilution of the product.

A little below the middle to the left is a rod-shaped bacterium that is partially out of focus. The content of the micro-organisms is approx. 107 per g
© Department of Veterinary Disease Biology 2011
Faculty of Health and Medical Sciences - University of Copenhagen
Denmark
Bean sprouts - Plate Count Agar
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Plate Count agar plates were incubated aerobically at 25° C for three days. The top row shows the plates in light from above and the bottom row is transilluminated.

The plates show a gram-negative mixed flora, which has a large tendency to break through to the surface of the agar. Several of the colonies are yellow pigmented. Part of the yellow pigmented colonies form a water-soluble yellow-green pigment (presumably Pseudomonas fluorescens), which is spreading in the agar. Pantoea agglomerans, which is part of the normal flora, will on testing for coliform bacteria show a positive reaction.
© Department of Veterinary Disease Biology 2011
Faculty of Health and Medical Sciences - University of Copenhagen
Denmark
Bean sprouts - Plate Count Agar closeup
Bean sprouts Bean sprouts
10-5 10-6
The water-soluble yellowish-green pigment is evident. The colonies are located on the surface is round, while the colonies lying down in the agar is lenticular.
 Not all of the yellow pigmented colonies are forming water-soluble pigment. Note the lenticular colonies in the depth.
© Department of Veterinary Disease Biology 2011
Faculty of Health and Medical Sciences - University of Copenhagen
Denmark