Inhibition of Mold Growth on Raspberries, What Works Best?
Brandon Krezeski, Jack McColl
Point Grey Secondary
Floor Location : J 135 R

We conducted this experiment in order to test which treatments worked better in inhibiting the growth of mold on raspberries. Of the many treatments currently in use, we chose thermotherapy, oven treatment, and vinegar treatment. We compared the efficacy of these treatments to each other, as well as to a control in which the raspberries remained untreated. Our hypothesis for the experiment was that if heating and dehydrating are two different ways of inhibiting mold growth, then the oven treatment would preserve the berries for the longest time. Further, we predicted that the vinegar treatment would be second best in terms of mold inhibition, followed by the thermotherapy. We also presumed that the control would confirm that no treatment led to the fastest raspberry decay.

We conducted our experiment by using six trials to confirm our results. For each trial, we used three raspberries for each of our 10 treatments (including the control): thermotherapy (3 treatments differing in time spent in water--1 minute, 30 seconds and 10 seconds), oven (3 treatments differing in time spent in the oven--25 minutes, 20 minutes, and 15 minutes), and vinegar treatment (3 treatments differing in the concentration of vinegar solution--3 parts water to 1 part vinegar, 2 parts water to 1 part vinegar, and 1 part water to 1 part vinegar), and finally the control, which was no treatment.

Our experiment proved that treatments for inhibiting mold on raspberries vary in effectiveness when directly compared. The vinegar treatment, specifically the 1 part vinegar to 1 part water solution, prevents mold the best, and almost just as successful is the thermotherapy for one minute, proving our hypotheses about the effectiveness of types of treatments wrong. Even though some treatments were not as successful as others, this experiment still proved that all of the treatments inhibited mold on raspberries better than no treatment at all which affirmed our hypothesis regarding the control. We were limited in this experiment by not being able to see microscopic mold and bacteria spoilage on raspberries because we lacked the proper equipment and microbiology knowledge, however due to our research indicating that raspberries have a low pH, which naturally inhibits most bacterial growth, we decided to limit the scope of our experiment to visible mold growth.

Our project has produced data and information that will provide people with knowledge of how to inexpensively and naturally prolong the shelf life of raspberries the most effectively. For example, the most effective treatments of vinegar solution of concentration 1 part water to 1 part vinegar, and thermotherapy for 1 minute achieve their purpose both naturally and relatively easily. Prolonging the shelf life of raspberries will reduce food wastage, allowing people to take more time to consume the raspberries, making food production more efficient.