This is a record of past guidelines used for hosting Dr. Beer Seminars. Each is slightly different as we have tried to change the seminars in the never ending task of perfecting the substances and levels used. Comments are provided to help you and us gauge our success.
Non-drinkable samples were made with non-food grade chemicals. If you have access to FDA approved additives, these if added in appropriate quantities (we make no guarantee of the toxicity of the above specified levels, you'll have to check this out and take responsibility on your own) are probably drinkable.
You'll need one bottle of doctored beer for every few people (assume 2 to 3 oz per person). You'll need bottle caps to recap after adding substances. All substances should be added less than 24 hours before, except for skunky and oxidized which need advance prep as indicated. In addition to beers for doctoring you'll need 8 to 16 oz reference beer for each person.
Prepare samples as noted. The order listed is the serving order we've been using I believe. The idea is to do the strongest nastiest one toward the end. Splitting this into 2 sessions is not a bad idea as the palette can get saturated and tired. The full range of samples takes 2-3 hours. Be sure to have some type of plain munchy like French or Italian bread and water (hopefully not skanky water) for palette cleansing. Basically you can proceed similar to competitions or other tasting events.
It is a good idea to serve these blind. Let people try to guess what they are tasting then after a minute or two tell them. Many people will pick this up. Stress the fact that flavor perception is devoid of the additional cues like sight that allow perceptual recognition. The idea behind doing this is to train and refresh (strengthen) the cognitive association between sensing and being able to assign (correctly) a descriptor to that sensation.
Feedback is encouraged. It will help us revise this program. Good Luck.
- Jay Hersh, Steve Stroud
hersh@expo.lcs.mit.edu
STROUD%GAIA@leia.polaroid.com
snail Mail:
Jay Hersh
aka Dr. Beer
15 Dunbar Ave.
Medford, Ma. 02155
Flavor/Aroma Amount Drink? Comment
- ------------ ------ ------ -------
1) Alcohol 10ml pure ethanol Y could have used a little more,
perhaps 12-15 ml/bottle
2) Clove 10ul eugenol N too strong, cut in half?
3) Winey 30ml Chablis wine Y Fine
(make sure it is fresh)
4) Estery 2.8ul t-Amyl Acetate Y OK, maybe increase 50-75%
(banana) was borderline this time
previously used .028ml which
was much too strong
5) Nutty 5 drops Almond Extract Y OK
6) Phenolic 4mg Phenol N Slightly weak, some people
couldn't detect this.
7) Buttery 5 drops butter extract Y OK
(diacetyl)
8) Sulfury 30 mg Potassium N Good
Metabisulfite (K2S2O5)
9) Skunky Previously dark stored, Y Good
fresh Molson in sun 3 days
10) DMS 0.08ul (made by diluting N OK
50uL pure DMS to 50ml
w/ pure ethanol, then
adding 80ul of this to each bottle)
11) Stale open bottles to air, recap, Y very light, needs more time
heat to 100F for 10 days
12) Sour 10ml white wine vinegar Y Too sour, cut in half
ul - micro Liter ml - milli Liter
Comments:
All amounts for 16oz. bottles. We used a light relatively flavorless beer that was free of original defects. We chose Carling Black Label. It was cheap, and of the 8 or so comparable cheap beers (why trash good stuff) it was the most defect free. The importance of a fresh beer to doctor can not be stressed enough. Remember to keep undoctored reference samples for side-by-side comparison during the session.
Substitutes:
Cloves or allspice can be made into a liquid extract (don't add these spices directly to beer or it will cause it to gush heavily!) and added in place of Eugenol. 2g of allspice is recommended but I have no direct experience with this (it sounds like way too much).
Banana extract if you can find it will be made from food grade Amyl Acetate (just as butter extract is basically food grade diacetyl, and Almond extract is Benzaldehyde). You can add this instead. Quantity unknown though 4-5 drops is my guess.
Metabisulfite tablets (Camden tablets) from a homebrew supplier can be substituted for Potassium Metabisulfite. These are used by winemakers to kill yeast. Quantity unknown.
Flavor/Aroma Amount Drink? Comment
- ------------ ------ ------ -------
1) Alcohol 12ml pure ethanol Y good
2) estery 90ul banana extract Y still way too low
perhaps try corn spirits
next time
3) nutty 60ul almond extract Y too low (was fine in Carling)
4) diacetyl 75ul butter extract Y good
5) phenol 9mg N
6) clove 2 eyedropper drops Y good
clove extract
7) Stale open bottles to air, recap, Y good this time
heat to 100F for 10 days
8) Skunky Previously dark strored, Y Good
fresh Molson in sun 3 days
9) Sulfury 22.5 mg Potassium N only half got it
Metabisulfite (K2S2O5) could be bumped up
10)Lactic 380ul 85% DSP Lactic Acid Y good
(i.e. food grade!!!)
11) DMS 0.08ul (made by diluting N OK
50uL pure DMS to 50ml
w/ pure ethanol, then
adding 80ul of this to each bottle)
ul - micro Liter ml - milli Liter
Comments: George Fix suggested using Corn Spirits to replace Banana extract for the estery. He indicated that these contain 1000 times as much esters per unit volume as beer. Some scratch calculations indicate that if this is correct, to doctor a beer to raise the ester level to 2 to 3 times threshold level (as defined in George's book by the Flavor Unit terminology) one would use 1ml of Corn spirits. We have yet to try this, but plan to do so soon. Please let us know if you do try this.