BENSON — Yui Salazar will be heading to the YES (Youth, Engineering and Science) Fair later this month with her scientific investigation that delves into the “five-second rule.”
The Benson Middle School eighth-grader recently designed and conducted an experiment using the scientific method to test bacteria growth on food that hits the floor.
“Many people believe that if you drop food on the floor and pick it up in less than five seconds, it’s not contaminated by bacteria and it’s still safe to eat,” Salazar said, while standing next to her display board that showcased the procedures she used for her experiment and its outcome.
“I questioned whether food that is dropped is still safe to eat and conducted experiments using apple slices for the food source,” she said.
Salazar used equal sized slices and dropped them on the floor using different time increments.
“One slice was on the floor for one second, one for three and one for five,” she said. “I also had one slice that was not dropped.”
Interestingly, the apple slice that did not come in contact with the floor grew the most bacteria, Salazar noted in her experiment. But the bacteria on the dropped, or “contaminated” slices was much brighter in color than what was growing on the slice that had not been dropped.
“The brighter colored bacteria is more dangerous if consumed,” Salazar said. “Through my experiment, I discovered that food that is dropped on the floor is unsafe to eat, even if it’s less than five seconds. But food that sits around grows bacteria as well,” Salazar said of her investigation and subsequent results.
Every year, Benson Middle School students design and conduct an experiment using the scientific method as they search for answers. The students come up with a scientific project, test a question and then reveal their observations and data in a step-by-step process.
Another Benson eighth-grader, Lydia Marks, won “Best of Show” for her project, “I set fire to the wood!”
Using four types of wood, she wanted to see which one would raise the temperature of water the most while burning.
“I tested oak, mesquite, maple and pine,” Marks said. “My hypothesis was that the denser the wood, the higher it would raise the water temperature, but the results for my experiment didn’t work out that way. Of the four different types of wood that I used, oak was the denest, but the least dense wood, which was pine, raised the water temperature the most.”
Marks said she’s excited about taking her experiment to the YES Fair this year and seeing how it does against all the other projects at the event.
For his project, Nathan Miles, also an eighth-grader, wanted to know how oxidation affects the pH of water by dropping a nail in water and testing the pH level.
The students’ investigations were showcased and judged at Benson Middle School’s recent science fair, with the top few projects in each grade awarded ribbons. The winning projects will be entered in the annual YES Fair at the Windemere Hotel and Conference Center, 2047 S. Highway 92 in Sierra Vista, with this year’s event scheduled from Feb. 25 through 27.
Every year, the YES Fair draws hundreds of science-minded middle and high school students from all over Cochise County for the judged competition where they win ribbons, certificates and money for top projects.
Sponsored by Sulphur Springs Valley Electric Co-op, fifth- through twelfth-grade students who live in SSVEC’s service area, as well as students from schools in Bisbee, Douglas, Nogales and Tombstone are eligible to enter science projects in the event.
Throughout the competition, display boards fill the Windemere halls and conference rooms with projects that explore all areas of science, engineering, math and technology.
Every year, two high school projects are selected as grand prize winners to compete in an annual Intel International Science and Engineering Fair — representing the world’s largest pre-college science competition — with this year’s event scheduled from May 10 through 15 in Anaheim, California.