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Science Rocks!

Yeast, Part II


your results

Sent in by:
Cara of MD

Feed the yeast!

Materials Needed

  • 3 packages of yeast
  • warm water
  • 3 clear, 16 ounce, plastic water or soda bottles
  • funnel
  • 3 balloons
  • rubber bands
  • various sugary liquids, like cola, apple or orange juice, and corn syrup



  1. Check with a grown-up before you begin.
  2. Cara of Maryland sent us the idea to do an experiment to see which liquids yeast like the best. When Matt and Estuardo did this on the show, their hypothesis was that the more sugar a liquid has, the more the yeast will eat it, and the more carbon dioxide it will produce. Here's how you can test it out.
  3. Add 1 package of yeast to each bottle.
  4. Fill each bottle 1/4 full with warm water.
  5. Fill the first bottle half way full with one of your sugary liquids, like cola.
  6. Fill the second and third bottles with different sugary liquids. Make sure you add the same amount of liquid to each bottle.
  7. Put a balloon over the opening of each bottle. The balloon that inflates the most will show which liquid produces the most carbon dioxide.

Which of your liquids do you think will produce the most carbon dioxide? Make a prediction, and then test it out. Be sure to send your discoveries to ZOOM!

Some of your Results

Tia, age 12 of Lawton, OK wrote:
it blew carbon dioxide in the balloon it was kool!

Elizabeth, age 8 of St. Louis, MO wrote:
I thought the cola was going to win. But the OJ won.

Shweta, age 10 of South Bend, IN wrote:
i used corn syrup, orange juice, and apple juice the biggest was corn syrup the 2nd biggest was apple juice and the smallest was orange juice.

Fanta, age 13 of New York, NY wrote:
when I did it cola was the one with the most codon dioxide.

Dustin, age 4 of Pauls, OK wrote:
it was cool. iliked it it blew up I liked it

Mohogany, age 10 of Missouri, TX wrote:
when me and my sister did it we discovered the cola gave off the most carbon dioxide. while the others produce less carbon dioxide, it was great for my science project thanks ZOOM!!!

2nd Grade of Germantown, TN wrote:
We did this experiment for our school science fair. We tested 5 liquids (vitamin water, orange juice, coke, kool aid, and corn syrup). We had a strange result. The coke had the most sugar but not the biggest balloon. We think it was because the yeast had TOO MUCH sugar to eat. We also noticed that the coke bubbles overflowed and went into the balloon. Next time, we might want to use a taller bottle and see what happens.

Alexis, age 10 of San Antonio, TX wrote:
The cola was in 1st place 2nd was a tie between orange and apple juice.

Danielle of Capitol Heights, MD wrote:
Cola gave more

Ali, age 12 of SK wrote:
It was really cool the balloons popped up and some were bigger than others! I did it for my science project last year!

Domanik, age 12 of Austin, TX wrote:
I used coke, oj maple syrup. The coke was in lead at first. but the oj was first. coke was 2nd maple syrup was 3rd.

Yolanda, age 10 of Chicago, IL wrote:
When I did it cola was the one with the most codon dioxide.

Dasia, age 10 of Calumet City, IL wrote:
first my ballon did not blow up. next I tried to do it agin and it blow up then it popped and yeast got everywhere. last my ballon blow up and stayed over night.

Alina, age 13 of St. Croix, VI wrote:
at first all the ballons were the same size but after awhile the orange juice ballon got realy big I was suprised cause orange juice is sour

Jillian, age 11 of Langley, BC wrote:
I did this for a Science fair progect. It took a long time for the balloons to blow up. You have to be very pacient

Elaine, age 12 of Boston, MA wrote:
Well... I did this project with class during science one day and we tried many liquids, some of them were in room temp and some of them were cold. The room temp. liquid fed the yeast better than the ones that were not in room temp. But as the day went on the teacher tested more liquids and the most sugary liquid fed the yeast the most and it inflated the balloon the most.

Ali, age 13 of GA wrote:
I did this many times and each time I got different results! What's wrong with that?

Madeline, age 8 of Fresno wrote:
I used apple juice, OJ, and Hawaiian Punch. At first, Hawaiian Punch blew up. But then OJ started to blow up. Then apple juice started to blow up. OJ turned out to be the winner. Apple juice was second place. Hawian Punch was last place. You have to be patient and wait.

Nisreen, age 11 of Brooklyn, NY wrote:
I did this project in 3rd grade and it was so cool the orange juice blew up the most.

Autumn, age 10 of CA wrote:
Cola got the biggest balloon.

Pat, age 9 of San Deigo, CA wrote:
I did it and grape worked the best.

Jordan, age 12 of Brooklyn, NY wrote:
I did this experiment with apple juice, raspberry iced tea n pepsi. Surprisingly da pepsi ate the most yeast instead of da apple juice. But the apple juice n pepsi was very close and the balloons blew up to be very big but the iced tea hardly did anything.

Vianni, age 13 of New York, NY wrote:
I did it with pepsi, sunny D, and Corn syrup. The pepsi was the biggest then Sunny D and last was the Corn Syrup.

Shantell, age 12 of San Jose, CA wrote:
I used apple juice, V8 vegetable juice, and berry flavored Gatorade! At first the V8 started out as the fastest, but then the apple juice beat it! The Gatorade was in last place, but an hour later it beat the V8. So, the apple juice was first, the Gatorade, and last was V8!

Sankavi, age 8 of Beaverton, OR wrote:
I did it with OJ, coke & water. I thought the coke would win but the Oj won.

Natasha, age 10 of Syracuse, NY wrote:
When I did this project I used RootBeer, Green Tea, and SunnyD. The RootBeer produced the most carbordioxide, Green Tea produced the secont most, and SunnyD. produced the least.

Ta'Cara, age 11 of Lancaster, SC wrote:
At first, the pepsi was the biggest, then it went down and the apple juice and the corn syrup blew up and stayed up.

Maya, age 9 of Alexandria, VA wrote:
I used OJ, apple cider, coke, diet coke, corn syrup. Diet coke went up first but, OJ won.( 16. 5 in. in diemeter)

Daniella, age 9 of Hazlet, NJ wrote:
The coke and the corn syrup worked the best. The apple juice didn't work at all.

not yet implemented