Winemaking

In the world of home winemaking there are those content with following a set of instructions and using only simple means to assess the production. You can make great wine with only a hyrdometer and a good palate. I, however, have more fun in trying to make my own testing equipment and coming up with different ways to make and test the wine. This is the reason I developed the BarrelBung. (I should say that after working on the BarrelBung project for a few months I found an old U.S. patent that was pretty much exactly what I came up with. This didn't really bother me, it was and still is fun to work on, even though someone else had the idea first - I still came up with it on my own.)


Aeration-oxidation test kit

Siphon method

Aeration-oxidation test kit

(SCROLL DOWN FOR DETAILED PICTURES!)

Monitoring the free and bound SO2 levels in wine is important, especially if you want to do MLF (as you need to keep SO2 low enough for MLF but not so low as to leave the wine totally unprotected). I looker around at different free So2 measuring methods and found that the cheapest and easiest method, titrets (named after titration), can have an error of up to 10 ppm. In the literature you will hear about two common methods: 1. aeration-oxidation and 2. ripper (what the titrets product is based on). It seems that the aeration-oxidation method is the way to go if one is going to be serious about accurate free and bound SO2 levels. The only problem is that this method is more complicated than the ripper based methods and requires one to either 1. go buy a test kit which can run from $100 (home winemaker cheap end) to $6,500 (idiot proof industry model that can test free SO2, pH, TA, volatile acidity...) or 2. make your own. I went the second route. I based my design of plans for the cheap home winemaker model. I needed to buy the following parts and or chemicals:

1.Generic medical tubing (the amount depends on how you want to set up your test... what kind of pump you use, what kind of vessels you are using...) (I found some old garbade tubing in a lab at work)
2. Reaction vessels (can be different sizes, need to hold at least ~50 ml but I would suggest using 125 ml flasks) (I garbage picked these from a elementary school)
3. two hole rubber stopper (2 of them sized to fit in the reaction vessels) (I bought mine for $0.62 each OnlineScienceMall)
4. air pump of some kind ( I used a "filter pump apsirator" that runs of water b/c it was the cheapest ($10.95 OnlineScienceMall). You can actually buy a small vacum pump or even use a fish tank air pump.)
5. 10 ml pipette ( you can get away with just one, but believe me you dont want to be cleaning it a bunch of times during the test) (you will need to use the pipette multiple times during the test so it is best to have a few laying around - one for each chemical)
6. pipette bulb (easy to use --> google pipette bulb and idiot proof direction will come up, cost me $5.95 OnlineScienceMall)
7. 3% Hydrogen Peroxide Solution (pharmacy generic brand is fine) 8. Phosphoric acid 10% (Northwestern Extract Co. $3.95 from local wine/beer making shop) (The plans I based my test off say to use 25%, I could not get that strength and I do not see any reason why 10% would not work. this acid is being used to drive out the SO2 from the wine sample, I therefore assume that if I used a lower strength the rate of the SO2 leaving my sample would be decreased so I simply ran my test for longer than required for 25% solution)
9. Sodium Hydroxide Solution 0.2 N (National Biochemicals $3.95 from local wine/beer making shop) (same as used for TA testing --> you need to cut this down to strength though for this test from 0.2 N to 0.01 N) 10. SO2 indicator (MT111 bought from MoreWine! online)
11. distilled water (buy it at your local food store)
12. silicone (for connecting the tubing to the two hole stoppers)
13. syringes (not really required but Ifind them useful to have around)
All of the parts pretty much go together without much explanation, see the pictures below. I will however comment on the glass bending. I first tried using my electric range - this did not work - I just eneded up snapping my first glass rod in half. So I lit a candle and this method seemed to work fine in getting the glass up to melting temps. From there all I can say is buy triple the amount of glass you need and practice a few times or elese you will end up with the ugly result I got (it works though!). My advice would be as follow for bending the glass: 1. remember that the glass is very hot and will burn your fingers 2. keep the glass moving so you dont get hot spots (these spots will tend to bend a lot leaving the finished result looking all lumpy) 3. the glass will cool and become hard very fast (this is where the trial and error comes in --> trying to get a nice uniform heat and bend job before the glass you just heated cools).
I should also mention that cutting 0.2 N Sodium Hydroxide down to 0.01 N is not easy if you try to only make a small amount (it is hard to accurately measure very small volumes). therefore I would recommend making 50 ml or so and saving it for future tests.

To avoid simply duplicating other's information on this test here, I will not comment on how the test can be actually carried out. See the instructions and videos provided on MoreWine!. In stead, I will show my set up in action and how the above peices fit together.

In stead of buying a ring stand to hold the aspirator, I simply used a rubber band and attached it to my distilled water jug.

Here you can see how the "plumbing" is conected. I had to buy a small fitting for my sink so I could attache the tubing into the sink's water supply.

The wine sample is on the right and the reaction vessel is on the left. During the test the color of the reaction vessel changes and you then know the test is working!

fancy looking peice of glass that is crucial for providing the vacuum I used to run the test.

My not so nice glass bendingattempts. It works - thats really all that matters. If I did it again it would look better. I finally got the hang of it by the last piece of glass.

I use the small syringe to titrate using the 0.01 N Sodium Hydroxide. It has very small volume markings on it that are easy to read.

Siphon method

Ever tried getting a liquid from one container to another using the siphon method? The first time I made up a wine kit I was at a loss as to how to start the siphon without my mouth touching the end of the tubing. (obviously you do not want your mouth in contact in the wine this early! It needs to sleep for a long time without the little bad guys that live in your mouth growing in it) I thought of priming the siphon line by pouring some wine into the end of the siphon hose using a measuring cup or perhaps my wine thief. This basically takes a long time and one will probably always have a spill. Another method would be to push the tubing down into the wine and then put your thumb over the end and lift the tubing out (this will pull up wine out of the carboy inside the tube --> works just like a wine thief) EXCEPT you then have put your potentially dirty tubing inside your wine and you now have a tubing coated in wine which will attract bugs and will drip wine all over the place. My solution --> push the end of the wine thief into the hose to be used for sihponing and put your mouth on the wine thief in order to draw the wine into the siphon hose. This lets you use your mouth to start the siphon with having your mouth coming into contact with the wine.