Science-fair finding allows girl to sample a croissant | Science News for Students

Science-fair finding allows girl to sample a croissant

She tested if pills could break down proteins in bread that can make some people sick
May 16, 2018 — 11:47 am EST

Croissants used to be Cassandra’s favorite food. But they contain gluten, which can make her very sick. 


PITTSBURGH, Pa. — For people with celiac disease, a restaurant menu can be a minefield. It’s something Cassandra Dods,18, has learned the hard way. She can’t eat many popular foods without becoming sick. Some companies sell pills online that they claim can help. But Cassandra wasn’t sure they would work. So she decided to test them. In the end, she was so confident in her results that she tried one of the pills herself.

Cassandra, who recently graduated from Tinturn Grammar School in Melbourne, Australia, has celiac disease. It’s a disorder in which the intestines cannot tolerate gluten — a pair of molecules that give baked goods their delicious chewiness. Eating gluten can leave celiac patients with dire stomach upsets and worse. Cassandra can’t consume bread, pasta, pizza and many other foods. She can’t even eat her past favorite food  croissants.

Of course, people who can’t eat gluten can ask for gluten-free foods. But gluten has a way of getting into foods where people might least expect it. “It happens quite a bit,” Cassandra explains. “The other day I had a milkshake. I thought it was normal. In fact, “there were pretzels in it!” Those pretzels? They contain gluten. “Why are there pretzels in a milkshake?” she asks. “It makes no sense.”

Cassandra isn’t alone. Around one percent of people worldwide have celiac disease. Anytime they accidentally eat gluten, they can end up with nausea, cramps and other painful problems. Some people buy food supplements that are supposed to help. The pills are sold over the internet and contain enzymes — molecules that can break down certain chemicals. Those enzymes are supposed to get to the gluten and destroy it before it sickens someone. But do they work?

Cassandra wasn’t really sure if she should trust their claims. She decided to test two different products. One contained an enzyme called caricain (KAIR-ih-kayn). It’s derived from a papaya plant. It can break down many different molecules — including gluten. The other contains a mix of enzymes — but the company doesn’t identify precisely which ones.

Cassandra lab
Cassandra prepares her samples for testing.
C. Dods

To find out if either product really broke down gluten, Cassandra went to the lab of Gregory Tanner. He’s a botanist — someone who studies plants — at the University of Melbourne.  

In his lab, the teen ground up the two types of pills. She also prepared another enzyme called trypsin (TRIP-sin). Everyone has this enzyme, which can help digest a bit of gluten. She put the pills and the trypsin into liquids that were meant to mimic the stomach and small intestine. One liquid was very acidic, like the stomach. It had a pH of around 3. The other solution was more neutral, like the small intestine. It had a pH of around 7. Then she added gluten from barley.

After giving the enzymes time to work, Cassandra ran a test called an ELISA. This is a test that can detect very small quantities of chemicals. She also ran another test called a Western Blot. It can separate molecules by their size.

The pill with the enzyme from the papaya plant worked very well. By the time it was done, there was almost no gluten left. The papaya enzyme worked in both the acid and neutral environment. It even worked after being boiled.

The other pill broke down some gluten, but not all. And it didn’t stand up to being boiled. But both pills performed better than trypsin.

Cassandra presented her results here, this week, at the Intel International Science and Engineering Fair (ISEF). This annual science competition was created by Society for Science & the Public and is sponsored, this year, by Intel. The event brought together almost 1,800 finalists from 81 countries to present their science-fair projects to the public and to compete for almost $5 million in prizes. (SSP also publishes Science News for Students and this blog.)

But how pills work in a dish may not mimic how they could work in the body. Cassandra decided to try the more effective pill from her tests. “I had an obsession with croissants before I became gluten-free, so my parents tried to find me good gluten-free croissants. But they are shockingly bad,” she says. “I thought if I was going to test it, I was going to have a croissant.” That way, she explains, “I would be happy even if I have a reaction.” She popped the pill and ate the pastry.

It worked. “I didn’t react,” she says. “It was really good!”

Even though she tried it for a test, Cassandra is not giving up her gluten-free lifestyle. “We don’t know the long-term effects” of eating gluten with these supplements, she says. But the teen carries them with her to take when she’s not sure if her food is entirely gluten-free. If she ends up accidentally downing gluten, at least she has a backup plan.

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Power Words

(for more about Power Words, click here)

acidic     An adjective for materials that contain acid. These materials often are capable of eating away at some minerals such as carbonate, or preventing their formation in the first place.

blog     Short for web log, these internet posts can take the form of news reports, topical discussions, opinionated rants, diaries or photo galleries.

caricain      An enzyme derived from the papaya plant. This molecule breaks chemicals into smaller pieces. It is sometimes used in supplements for people with celiac disease to help them digest gluten.

celiac disease     (also known as sprue) A disorder in which the immune system attacks the small intestine after it encounters foods containing gluten, a wheat protein. People with this disease suffer from stomach pain, constipation, diarrhea and a constant feeling of fatigue. They must avoid gluten-containing products like bread, cake and cookies.

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.

digest     (noun: digestion) To break down food into simple compounds that the body can absorb and use for growth.

disorder     (in medicine) A condition where the body does not work appropriately, leading to what might be viewed as an illness. This term can sometimes be used interchangeably with disease.

ELISA     (or enzyme-linked immunosorbent assay) This is a test used to detect very small amounts of chemicals in a liquid.

engineering     The field of research that uses math and science to solve practical problems.

enzymes     Molecules made by living things to speed up chemical reactions.

gluten     A pair of proteins — gliadin and glutenin — joined together and found in wheat, rye, spelt and barley. The bound proteins give bread, cake and cookie doughs their elasticity and chewiness. Some people may not be able to comfortably tolerate gluten, however, because they have an allergy to it or suffer from celiac disease.

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 75 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. 

internet     An electronic communications network. It allows computers anywhere in the world to link into other networks to find information, download files and share data (including pictures).

liquid     A material that flows freely but keeps a constant volume, like water or oil.

molecule     An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).

nausea     The feeling of being sick to one's stomach, as though one could vomit.

obsession     A focus on certain thoughts, almost against your will. This intense focus can distract someone from the issues that he or she should be addressing.

online     (n.) On the internet. (adj.) A term for what can be found or accessed on the internet.

pH     A measure of a solution’s acidity or alkalinity. A pH of 7 is perfectly neutral. Acids have a pH lower than 7; the farther from 7, the stronger the acid. Alkaline solutions, called bases, have a pH higher than 7; again, the farther above 7, the stronger the base.

solution     A liquid in which one chemical has been dissolved into another.

SSP     Short for Society for Science & the Public. This nonprofit organization was created in 1921 and is based in Washington, D.C. Since its founding, SSP has been not only promoting 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). SSP 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).

supplement     (verb) To add to something. (in nutrition) Something taken in pill or liquid form — often a vitamin or mineral — to improve the diet. For instance, it may provide more of some nutrient that is believed to benefit health. It may also provide some substance to the diet that is claimed to promote health.

trypsin   An enzyme in the digestive tract of mammals that breaks down many different molecules in food.


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