Marissa Salinas really likes hamburgers. In fact she calls them her weakness. But, what she doesn’t like in her hamburgers is E. coli bacteria.
Salinas, and her science project that measured how different spices affected bacteria levels in hamburger meat, was just one of the many students and science projects on hand Tuesday at the California State Science Fair at the California ScienCenter in Los Angeles.
Salinas, a ninth-grade student at Sanger High School in Northern California, said she squeezed into the state fair as an alternate and had spent about three months working on her project.
Mixing various solutions of hamburger meat with different spices, then freezing and incubating parts of the solutions, she concluded that oregano helped reduce bacteria levels better than garlic.
"Not only do spices make it healthier – it makes it taste a lot better,” Salinas said.
Science interests her because it allows people to methodically prove they are correct, adding that she is "really good at proving what I think is correct."
This year's science fair had over 900 students participating in 24 categories, such as structural engineering, aerodynamics and zoology. Over 300 academic and professional scientists and engineers volunteered to judge the students' projects, said a ScienCenter spokeswoman. A combined total of $50,000 was being awarded, with the senior with the science project of the year taking home a $10,000 prize.
St. Francis High School junior Alexander Sercel said his science project about how plant transpiration is affected by carbon dioxide levels in the atmosphere probably wouldn't win the fair's top honors.
A little known fact, Sercel said, is that water vapor is the most powerful greenhouse gas on the planet. Through experiments he was able to observe how transpiration, akin to a plant sweating, slows down when there's less water vapor in the atmosphere – meaning that global warming and thermal blanketing are probably slowing down when there’s more CO2, Sercel said.
“So you get this negative feedback mechanism of transpiration that helps keeps the planet in balance.”
Sercel, of La Canada, said he originally had a science partner who left him in the lurch, and estimates he had spent over 100 hours working on his project since January.
Volunteer judge and microbial ecologist Dr. Rocco Mancinelli said students' science projects often reflect what they see at home and how they are intrigued by certain aspects of their environment.
Most young children have a natural inquisitiveness about their environment and surroundings, and it is early on in a child’s education when they get the “itch to develop that first spark of interest” in science and scientific creativity, Mancinelli said.
Being able to develop that potential doesn't happen solely by reading and memorizing textbooks, but rather comes from hands-on experience and asking questions, he said. Science curricula should build upon inquisitiveness and not “try to squelch it intentionally or unintentionally.”
Volunteering for his third straight year, Mancinelli said students' science projects often range from those conducted in university settings or government laboratories to others that are interesting and original and done in houses, garages and kitchens.
The daughter of an UC Riverside entomologist, Caitlin Redak said she had access to a UC Riverside lab while studying black widows' webs. The ninth-grader at John W. North High School in Riverside said fair officials prohibited her from using the poisonous spiders in her display out of safety concerns.
Redak said her love of science and spiders led her to research the strength and elasticity of spider webs. She said scientific advancements in the manufacture of suspension bridges, bulletproof vests and fishing lines all owe some degree of success to spider webs.
One of the discoveries Redak made while conducting her experiments: "The bigger the spider, the stronger the web."