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Tomato Paste

Four devices were delivered to HML by Victor De Franco Levi on May 4, 2010; as well as, several cans of Contadina tomato paste(Contadina Foods, inc. 6 oz) to be tested over a period of ninety-six hours for aerobic bacteria, yeast, and mold.

The four devices were prepared before testing following the procedure in the Engeenuity device handling instructions.

Two devices were placed in the first room greater than twenty feet apart from each other.

The remaining two devices and the control sample were all placed in separate rooms.

The canswere all opened, and all the cans other than the control were placed on the respective device.

A time zero control was taken from the control sample. The tomato paste cans remained on the devices for 96 hours with samples taken at forty-eight hours, seventy-two hours, and ninetysix hours for bacteria, yeast, and mold testing.

Aerobic bacteria samples were plated with an agar overlay, and incubated for forty-eight hours at 35oC.

The yeast and mold samples were also plated with an agar overlay, but were incubated at room temperature for five to seven days.

The 96 hour sample control was allowed to grow an additional 48 hours due to high amount of yeast and slower growing molds.

Based on the initial tests, it appears that the devices inhibited the growth of microbes to some extent, especially in regards to the yeast. The effectiveness of the devices appeared to diminish after the seventy-two hour mark with respect to the aerobic plate count. Growth from the samples were enumerated from aliquots that had been retrieved from the source placed on the devices; thus, it is possible that device may have maintained inhibition of microbial growth had the plated samples been left upon the devices and analyzed versus removed and allowed to grow in a separate location. For future testing, an experiment could be performed with the device placed in the incubator with a set of petri dishes comparing dishes without the device, and determine if any further reduction could be achieved.

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