The Effect of Heat and Growth on the Survival of Bacteria free essay sample

Aims The purpose of the two experiments was to determine the fundamental effects that temperature has on the growth and survival of bacteria. During the first experiment five different bacterial broth cultures of Escherichia coli, Pseudomonas fluorescens, Enterococcus faecalis, Bacillus subtilis and Bacillus stearothermophilus were individually incubated at temperatures of 5, 25, 37, 45 and 55Â °C for one week in an aim to distinguish the effect temperature has on growth and survival of the five different species. After one week they were observed for distinguishable changes by the turbidity showing an indication of bacterial growth, or the clarity an indication of no survival. The second part of the experiment was to examine the effect temperature had on the survival ability of the five bacteria mentioned above. One of the five bacterial species were allocated per work bench for individuals to create broth culture with and expose to temperatures of 40, 60, 80 and 100Â °C for 2, 5, 30 and 90 minutes.