Barnyard science: Check out this fowl research
PITTSBURGH, Pa. — People eat a lot of chicken. In fact, there are more chickens on Earth than any other bird. People around the world rely on chicken and their eggs for protein. And of course, these birds are pretty tasty. But they aren’t just about food. Chickens can also provide the basis for a good science fair project, as four teens showed last month.
An Australian girl tested how best to store eggs so that they remain tasty and healthy. Another pair of teens from Malaysia showed why ground-up eggshells might provide more fire-resistant surfaces. A fourth teen, from Egypt, investigated the insulating potential of chicken feathers.
All four described their projects at the Intel International Science and Engineering Fair. This competition was created by and run by Society for Science & the Public. It is sponsored by Intel. The fair brings together nearly 1,800 students from 81 countries to share their research. (The Society also publishes Science News for Students and this blog.)
The chicken projects showcased at this year’s Intel ISEF promote safety and find new uses for what might otherwise be wasted. They show how young scientists can use local resources to answer questions and solve problems.
Science on the half-shell
Chickens have always been a part of life for Emma Serisier. “I live on a farm back home in Australia,” explains the 16-year-old junior from Bishop Druitt College in North Boambee Valley, Australia.
The 100 chickens on her family’s farm produce 20 to 30 eggs each day. “There’s a worldwide debate about where to store eggs,” she notes. “Back home in Australia they can be stored on the shelf. Sometimes they’re sold that way.” In contrast, she notes, here in [the United States] all eggs are stored in the fridge.” Why? Farmers wash U.S. eggs to get them clean. But that also wipes off a protective coating — one that prevents germs from getting in. So these now-unprotected eggs must be kept cool to slow the growth of bacteria. In contrast, unwashed eggs can go from the chicken straight to the store, protective coatings intact.
Emma’s family had never worried about a need to keep their stored eggs cold. But did storing them at room temperature compromise their flavor? “I wanted to find out,” the teen says. And with that, a science-fair project was born.
Eggshells are full of holes, known as pores. “Eggs have up to 17,000 pores,” Emma notes. These let oxygen in, and water and carbon dioxide out. The temperature at which eggs are stored might affect how much water and carbon dioxide leave them. And that might change how long the eggs would be safe to eat.
Emma's Araucana hens lay eggs with light green shells. The teen collected 12 eggs from her hens, then chilled three in the fridge at 5° Celsius (41° Fahrenheit). Three more sat on a shelf at room temperature (24 °C or 75 °F). She stored another three under a heat lamp for two weeks. (“I wanted to mimic eggs in a hot car,” she explains.) The final three eggs sat outdoors, exposed to wind and weather.
Every day for 16 days, Emma measured each egg’s mass. She also put a flashlight up against each. to look at air pockets inside the shells. This offered one gauge of how much water might be entering or leaving each egg. On the last day she cracked each egg open.
Those that had been stored on the shelf or in the fridge only lost about two percent of their mass to evaporation. Their yolks and whites looked fine, just like a healthy (if slightly old) egg. The eggs under the heat lamp, though? “They were so gross. The yolks had coagulated,” Emma says. “I would not eat them!”
The only thing grosser were the eggs that had been stored outside. It had rained on four of the test days, and some of that water slipped through the pores and into the eggs. These had “sort of scrambled. They didn’t have a yolk — it was just a liquid mixture,” she says. And, well, “they smelled like rotten eggs.”
Emma concluded that high temperatures (like a heat lamp) and fluctuating conditions (like sitting outdoors on warm or rainy days) can make eggs suffer. She now concludes that a cool, dry place makes for good eggs — on the shelf or in the fridge.
Firing up the shells
For Emma, what’s inside the shell matters most. In fact, those shells will become trash once a cook cracks one open to make a cake or omelet. Nur Helmi Arwizar and Muhammad Shazwan Sobri, both 17, want to turn that waste into a resource — one to “save lives.”
The two seniors attend MARA Science Junior College in Nibong Tebal, Malaysia. It’s a common thing for us to hear about fires that cause death,” says Helmi. The teens reasoned that powdered eggshells might slow down house fires. Slower fires would give people more time to escape.
But why eggshells? It has to do with their chemistry. Calcium carbonate gives those shells their strength. The same chemical is an ingredient of many rocks, such as limestone. As it burns, calcium carbonate releases carbon dioxide. Being heavier than oxygen, that carbon dioxide stays close to the ground or to some burning surface. This keeps oxygen from fueling the fire. Indeed, that carbon dioxide release should actually slow a fire’s spread. Or that’s what the teens hypothesized.
To test that, Helmi and Shazwan collected the shells of eggs that had been used by their school’s cafeteria. After grinding them into a powder, they mixed the shells into house paint. The teens tried different ratios of shell powder to paint — from 0 to 80 grams (0 to 2.8 ounces) in every 50 milliliters (1.6 ounces) of paint. They used both latex (water-based) and oil-based paints. Then, the pair painted wood blocks with each recipe.
Later, Helmi and Shazwan held the dried blocks close to a flame and measured how long each took to ignite. Those coated with shell-free paints caught fire in about 30 seconds. Paint having the most shell in it didn’t catch fire for more than 6.5 minutes.
Both water- and oil-based shell-treated paints took longer to burn. But the oil-based paint is thicker, Helmi says, so the ground eggshell spread more evenly within it.
“We want to collaborate with a university,” Shazwan says, to refine this product and spread the word of its life-saving potential.
Feather your nest
Shells aren’t the only part of a chicken that normally goes to waste. So will its feathers. “Because we consume so many chickens around the world, we have huge amounts of chicken feathers left over,” observes Amira Abdelazim, 17. Some of that gets ground up and fed back to other chickens as feed. The rest will be thrown away or burned. Amira, a junior at El Menia Preparatory Secondary School for Girls in New Menia, Egypt, found a better use for this resource: “as a green organic insulation.”
Insulation is material used to keep heat from moving into or out of buildings. This will help keep people warmer in winter and cooler in summer.
To figure out what chicken feathers are made from, Amira turned to a spectroscope. This device measures light bouncing off of a surface. The colors given off will correspond to the chemicals in it.
The chemical makeup of chicken feathers turned out to be very similar to the fiberglass widely used as insulation today. These data seemed to confirm chicken feathers might make good insulation.
Now came the test. Amira took an insulated metal bottle and replaced its original insulation with ground up chicken feathers. Then she poured in a boiling liquid. She measured its temperature over time to see how quickly it cooled. She did the same thing to the liquid that she poured into a metal bottle with no lining and to one with a vacuum-lined jacket (known to keep liquids very hot for a long time). She checked the temperature inside each bottle after 24 hours.
Liquid in the unlined bottle had cooled to room temperature — 24 °C (75 °F) — by the next day. But the drink in the vacuum-lined bottle was still a toasty 57 °C (134 °F). The chicken-feather insulation allowed the liquid to cool to around 31 °C (87 °F).
Clearly, the chicken feathers didn’t work as well as the vacuum lining. Still, Amira concludes, feathers might find use insulating buildings. They “are much, much cheaper” than conventional building insulation, she notes. “One ton of chicken feathers would cost $8,” she says. An equivalent amount of synthetic fiber, she says, costs $1,200.
Amira isn’t the only researcher looking to use chicken feathers for this purpose. A company in England is working to transform chicken feathers into a range of products — including insulation. Amira has similar goals. She says “I hope to turn my project into a factory to make thermal products from chicken feathers.”
(for more about Power Words, click here)
bacteria (singular: bacterium) Single-celled organisms. These dwell nearly everywhere on Earth, from the bottom of the sea to inside other living organisms (such as plants and animals).
blog Short for web log, these internet posts can take the form of news reports, topical discussions, opinionated rants, diaries or photo galleries.
calcium carbonate The main chemical compound in limestone, a rock made from the tiny shells of ancient marine organisms. Its formula is CaCO3 (meaning it contains one calcium atom, one carbon atom and three oxygen atoms). It’s also the active ingredient in some antacid medicines (ones used to neutralize stomach acids).
carbonate A group of minerals, including those that make up limestone, which contains carbon and oxygen.
carbon dioxide (or CO2) A colorless, odorless gas produced by all animals when the oxygen they inhale reacts with the carbon-rich foods that they’ve eaten. Carbon dioxide also is released when organic matter burns (including fossil fuels like oil or gas). Carbon dioxide acts as a greenhouse gas, trapping heat in Earth’s atmosphere. Plants convert carbon dioxide into oxygen during photosynthesis, the process they use to make their own food.
chemical A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.
chemistry The field of science that deals with the composition, structure and properties of substances and how they interact. Scientists use this knowledge to study unfamiliar substances, to reproduce large quantities of useful substances or to design and create new and useful substances. (about compounds) Chemistry also is used as a term to refer to the recipe of a compound, the way it’s produced or some of its properties. People who work in this field are known as chemists.
compound (often used as a synonym for chemical) A compound is a substance formed when two or more chemical elements unite (bond) in fixed proportions. For example, water is a compound made of two hydrogen atoms bonded to one oxygen atom. Its chemical symbol is H2O.
fiber Something whose shape resembles a thread or filament.
fiberglass A material made of glass strands.
gauge A device to measure the size or volume of something. For instance, tide gauges track the ever-changing height of coastal water levels throughout the day. Or any system or event that can be used to estimate the size or magnitude of something else. (v. to gauge) The act of measuring or estimating the size of something.
green (in chemistry and environmental science) An adjective to describe products and processes that will pose little or no harm to living things or the environment.
hypothesis (v. hypothesize) A proposed explanation for a phenomenon. In science, a hypothesis is an idea that must be rigorously tested before it is accepted or rejected.
ignition (in chemistry) The act of igniting a fuel in combustion, such as natural gas or gasoline. (v. ignite)
Intel International Science and Engineering Fair (Intel ISEF) Initially launched in 1950, this competition is one of three created (and still run) by the Society for Science & the Public. Each year now, approximately 1,800 high school students from more than 80 countries, regions, and territories are awarded the opportunity to showcase their independent research at Intel ISEF and compete for an average of almost $5 million in prizes.
limestone A natural rock formed by the accumulation of calcium carbonate over time, then compressed under great pressure. Most of the starting calcium carbonate came from the shells of sea animals after they died. However, that chemical also can settle out of water, especially after carbon dioxide is removed (by plants, for instance).
mass A number that shows how much an object resists speeding up and slowing down — basically a measure of how much matter that object is made from.
model A simulation of a real-world event (usually using a computer) that has been developed to predict one or more likely outcomes. Or an individual that is meant to display how something would work in or look on others.
organic (in chemistry) An adjective that indicates something is carbon-containing; a term that relates to the chemicals that make up living organisms. (in agriculture) Farm products grown without the use of non-natural and potentially toxic chemicals, such as pesticides.
oxygen A gas that makes up about 21 percent of Earth's atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism).
pore A tiny hole in a surface. On the skin, substances such as oil, water and sweat pass through these openings.
protein A compound made from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. Among the better-known, stand-alone proteins are the hemoglobin (in blood) and the antibodies (also in blood) that attempt to fight infections. Medicines frequently work by latching onto proteins.
ratio The relationship between two numbers or amounts. When written out, the numbers usually are separated by a colon, such as a 50:50. That would mean that for every 50 units of one thing (on the left) there would also be 50 units of another thing (represented by the number on the right).
Society for Science and the Public A nonprofit organization created in 1921 and based in Washington, D.C. Since its founding, the Society has been promoting not only public engagement in scientific research but also the public understanding of science. It created and continues to run three renowned science competitions: the Regeneron Science Talent Search (begun in 1942), the Intel International Science and Engineering Fair (initially launched in 1950) and Broadcom MASTERS (created in 2010). The Society also publishes award-winning journalism: in Science News (launched in 1922) and Science News for Students (created in 2003). Those magazines also host a series of blogs (including Eureka! Lab).
spectroscope An instrument to used to measure wavelengths of light or other types of radiation and their intensity. When used to observe a gas, it can serve as an indicator of the atoms or molecules making up that gas.
synthetic An adjective that describes something that did not arise naturally, but was instead created by people. Many synthetic materials have been developed to stand in for natural materials, such as synthetic rubber, synthetic diamond or a synthetic hormone. Some may even have a chemical makeup and structure identical to the original.
thermal Of or relating to heat. (in meteorology) A relatively small-scale, rising air current produced when Earth’s surface is heated. Thermals are a common source of low level turbulence for aircraft.
vacuum Space with little or no matter in it. Laboratories or manufacturing plants may use vacuum equipment to pump out air, creating an area known as a vacuum chamber.
waste Any materials that are left over from biological or other systems that have no value, so they can be disposed of as trash or recycled for some new use.