For this study five probiotic drink supplements were compared. Specifically, for each drink, bacteria were isolated, identified, and quantified to determine if the product contained the bacteria specified by the manufacturer. The products examined were Danone Actimel, Optimil, Muller Vitality, Nestle Munch Bunch, and Yakult light. Methods included gram staining, bacterial culture on selective media, bacterial population assessment, determination of a raised overnight temperature on bacterial population, and photography. Results were that: Each sample contained lactobacilli; Danone contained diplococci and gram positive rods; Optimil, Nestle, and Yakult contained gram positive rods and gram positive cocci; and Muller contained gram positive cocci; all bacteria except one found in the Muller sample, were able to utilize the Lactose which indicated the presence of lactose fermenters; there were differences in the number of viable bacteria that were able to thrive on the three media under anaerobic conditions; each sample grew on each medium but with differences in numbers present; and colony counts were higher in the Danone, Optimil, and Muller sample and they decreased in the Nestle and Yakut sample due to refrigeration time.
The following discussion presents a summary of the results, how they relate to the study introduction and rationale as well as previous research, and how findings add knowledge to existing research. This is followed by a critique of the methodology, with conclusions and recommendations for future research.
In summary, results were that each sample contained lactobacilli: Danone contained diplococci and gram positive rods; Optimil, Nestle, and Yakult contained gram positive rods and gram positive cocci; and Muller contained gram positive cocci. All bacteria except one found in the Muller sample, were able to utilize the Lactose, which indicated the presence of lactose fermenters. There were differenc...