Root beer as 7th grade science lab...wisdom?

**TimBrewz** · 01-16-2009, 06:29 PM

I am a 7th grade science teacher who just happens to brew....I want to make root beer with my students and I think I have most of the lab planned.I am using Gnome extract and following the recipe from the Gnome website, just scaling it down to a 2L (1/2 gal) size for each group of kids.

The plan is:

Put kids in groups of 4

Each group get one clean 2 liter bottle, .4 oz Gnome Root Beer extract, 8 oz sugar, 1500 ml water, 1 2000 ml beaker, 1Hot plate.

1.Students heat 1500 ml water to 130f, add .4 oz extract and 8 oz sugar.
2. Stir to solution.
3. Remove beaker from heat, cool in cold water bath in lab sink to 80f.
4. Add chilled extract solution to 2 liter bottle, top off with water. Put cap on tightly and shake to mix new water well.
5. Bring bottle(labeled with sharpie) to walk in fridge in cafeteria.
6. Let root beer chill overnight to 40f and force carbonate at 40 psi. I plan to hook up each bottle to a Carbonator at 40 psi and shake hard for about 1 minute, then let rest again in fridge overnight.
6. Day 3 -enjoy!

My real question is: Will the force carbonating method work if I just hook up each bottle for a minute or so and shake it until I hear no more CO2 entering the rootbeer? I am I right that root beer is usually served around 3.0 volumes? ( I will try this at home first-but won't be able to do so for a while.)

Does anyone see any errors in my plan? Any wisdom?

By the way, the lesson does target National Science Standards: concentrations, dilution, solubility, solutions, solutes, pressure, energy, applied lab skills. It is also fun and yummy, which is huge for 12 year olds (and 38 year olds!)I just had to throw that in, as my principal was on my case

Thanks, Tim

The Blow Leprechaun · 01-16-2009, 09:15 PM

You don't want them to use yeast as well?

**TimBrewz** · 01-16-2009, 10:12 PM

No, I can't use yeast.(though I would rather do it that way) There is a zero alcohol policy in Public Schools, so even the trace amounts of alcohol created by bottle conditioning is not allowed. So force carbonating is the only method I can use.

k1v1116 · 01-16-2009, 10:49 PM

I dont have much experience with force carbing but soda is very highly carbonated so I think it would need more time. if you want to play around with fermentation you could try making some old fashion pickles or sauerkraut, no alcohol but lots of fermentation although I doubt it would interest the students as much.
Slightly off topic, my high school had a similar policy (****ing bureaucrats) but we learned about yeast in anaerobic respiration in 9th grade bio and thats what got me into brewing. they wouldn't let us play with yeast in class but if you explain fermentation to them in class some will be inspired to go home and experiment themselves.

**Yooper** · 01-16-2009, 11:00 PM

It takes a little while to force carb a 2 L bottle at 40 psi. Chill it first, then add it to the gas and shake as you described. Do that several times over the next 24 hours. Not just once, though- it'll need it a couple of times. My ginger ale was done this way, and took closer to 48 hours to be nicely carbed.

You don't have to chill the extract/sugar mixture. Just add it to the water in the soda bottle, and top up to the top with more cool water. Actually, you don't have to heat the water at all. You can just add the sugar and extract to the water and shake the heck out of it.

**TimBrewz** · 01-19-2009, 01:53 PM

Thanks the response Yooper. That helps a lot!

monty73741 · 01-19-2009, 04:20 PM

Yeah IT suks u cant use yeast, It would be the kids would actually learn something about chemisty & biology. LOL You should see if the cafeteria is selling anything naturally carbonated LOL

**conpewter** · 01-19-2009, 04:39 PM

So how is the science budget looking for 7 carbonator caps and a 7 outlet Co2 manifold? I imagine while it is not in use in the classroom it could be put to use elsewhere....

**TimBrewz** · 01-19-2009, 10:54 PM

Actually the budget is not good right now- I had to present this idea from a very oblique angle with my principal. Lucky the supplies are just about 50 cents per student and the kids did some PR for me by telling everyone that we ARE making root beer

Just 2 carbonator caps and one double CO2 outlet. So I will be a busy guy trying to carbonate 25 bottles of root beer.

**Moonshae** · 01-20-2009, 12:18 AM

What if the class blended their individual samples in a keg (or few) and you force carbed them? If you've got a counter pressure filler, you could fill their bottles back up once carbed, and it might be a lot easier on you. Except, of course, you've got a whole bunch of root beer kegs to clean.