Tuesday, January 15, 2013

We're Making Whiskey! Organic Chemistry

First Organic Chemistry lab was today.

The teacher has us making Rum! The purpose of todays lab was to teach us the process of distillation in a hands-on way. Distillation is one of several ways to purify organic compounds (crystallization was another method we discussed).

To do this experiment we took the following steps:


 1. We added 200 ml of diluted molasses (diluted with water and sugar) to a large Erlenmeyer flask,

Note: the instructor did not tell us how much he diluted the molasses, but that won't matter as you'll see how to calibrate your molasses and water using a hydrometer.
I recommend adding 1 ounce of molasses, 1.5 ounces of sugar (about one tenth of a pound), and 200 ml of distilled (bottled) water as a base solution.


2. Then we added 50 ml of yeast nutrient (to help the yeast grow and maintain).














3. We used a device called a Hydrometer at this point to see what our percent alcohol would be. This is a very simple device that works off of gravity.

  - To use one, you fill up a graduated cylinder (or any very skinny and tall container) with the solution.
  - You drop the hydrometer in and it will float. Wait for it to settle down and then you read where the water mark is on the hydrometer. Where the water mark is, is your percent alcohol potential.
  - This device works based on how much the device should float for every unit/volume of molasses or sugar added.

We had to ensure that our expected percent alcohol was between 10 and 16 percent.

4. Next, in a separate container, we soaked 5 grams of brewer's yeast in about 50 ml of tap water for 15 minutes.


5. After the soak time we dumped the yeast into the flask, put a rubber stopper in it, and shook everything up vigorously.

Note: The Rubber stopper had a hole in the middle.


 The hole is designed for an Airlock to be inserted into it, which keeps oxygen out (yeast make alcohol under anaerobic conditions). It not only keeps oxygen out, but it also allows carbon dioxide to escape (so too much pressure doesn't build up). Yeast produce carbon dioxide as a waist product while fermenting the sugars. The airlock looked like this one

NOTE: a poor boy airlock can be made by putting the mouth of a balloon over your bottle. The balloon needs to be able to expand quite a bit without bursting or releasing from the bottle.

7. We filled the airlock slightly over half way with water and then inserted the airlock into the rubber stopper

8. Now, we wait for about two weeks.

A few notes:
A. Light kills yeast so keep the yeast closed up until you're ready to use it
B. Place the bottle in a cold, dark, dry area
C. The instructor told us that our 16% alcohol would be distilled down to 50%. it would have a volume of about "1 shot," he told us. And we would then distill it again to about half of that volume and it would be approximately 190 proof (95%).
D. The lab stated that making the solution just "slightly" acidic would help prevent bacterial growth. The bottom line is, use clean equipment. And if you're on the cautious side, a few drops of lemon juice, orange juice, or vinegar will not hurt at all.
-- A few drops does not mean teaspoons. It means drops

E. I'll post another blog later for poor boy distilling as well as instructions on how we actually go about distilling our brew.

This blog has an excellent idea for a homemade still!


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