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Basic Internet Glaze Course

By Lili Krakowski


There is nothing difficult about glaze calculation.   Some people want to
make it appear mysterious and special for their own advantage.  As I have no
patience with this attitude,  I wrote this simple course.
You will need:
1. A pencil, paper, preferably with little squares on it.
2. A  calculator.
3. Several cans or packages of food with the contents and calories printed
on them.
4. A book which lists all the materials and their ingredients and their
atomic and molecular weights.  Lists are found in Rhodes, Fraser, several of
Emmanuel Cooper's books, and Michael Bailey's. I do not lug my books around,  just photocopy the pages I need and keep them by my side.
 5. A table to sit at, a good light, the phone on the answering machine, and
coffee or tea at your elbow.
Look at the food ingredient labels.  What do you see?
You see that foods are made up of carbohydrates, fats, proteins, and some
ancillary goodies.
We will discard the ancillary goodies and treat them as we do colorants.
But the carbs, fats, and proteins, are analogous to the melters, (fluxes)
stickers (primarily alumina) and glass formers (primarily silica).
Consider  a perfect diet for yourself the equivalent of a glaze.  One person
is still growing; one is pregnant, one wants to gain weight (there ARE
people like that) one person wants to lose weight.
What would they do?

Each would look at the carbs and proteins (4 calories per gram) and at the
fats (9 calories per gram)  and say "I should have X calories a day."
When you start on a glaze you look at the ingredients and say:  I want a c.6
shiny transparent glaze.  (Equivalent to saying "I need to lose 10 pounds")
You are setting a goal.  You are designing a diet or a glaze to achieve a
specific result.
With your diet,  you would study some charts and figure out that the
recommendation is  X, and that you should have A % carbs. B% fat, and C%
This was not handed down to Moses on Sinai.  This was achieved by study     and "research"  by nutritionists.  And glaze limit formulas were achieved by
glaze study and research.  (Limit formulas are the parameters within which
glazes of particular types fall.  For a particular type of glaze at a
specific temp the limit formula indicates just about how much you want of
specific ingredients. (Analogous to the cookbooks telling you what
proportion of different starches are used to thicken X amount of liquid.)
Not all books carry limit formulas and but by looking at glaze formulas  you
get a general picture.
Now I went and got some food packages:

Chick peas:   130 calories per serving 22 gms carb. 6 gms protein   9 gms
Colby cheese 110 calories per serving (ps)    0 carbs,  7 gms protein   9
gms fat
Lt cream cheese     70 cals ps  2gms carb    2 gms protein   4 gms fat
Sardines      190 cals ps   2gms carb  18 gms protein  12 gms fat
Soup      100 cals ps   17gms carb  7gms protein  1.5 gms fat
Let us go on and assume that for your diet you want 1200 calories per day,
and do not care how you get them.
You simply add up all the calories in the foods, which gives you 600
calories.  You then eat two servings of each item.
But that is not what you want.  Calories alone don't do it.  Your
nutritionist will tell you ok,  in your 1200 calorie diet-AND THIS IS ONLY
SOMETHING I MADE UP AS ANALOGY-you want 700 calories of carbs, 100 of fat,  and 400 of protein.

Very good.
You look at the foods above and say ok:  17 gms of carbs in the soup give me
68 calories.  Nor very much. You look at the chick peas.  22 gms gives you
88 calories.  Well,  if you had 4 servings of soup and 5 of chick peas you
would be just about right.
However what about the protein?  The chick peas give you 120, and the soup
112 calories.  So you are short 168 calories of protein.
The sardines give you 18 gms which is 72 calories, and 2.2 is 158.4. Close
But wait:  You are getting  405 calories of fat with the chickpeas, and 54
calories of fat with the soup...
All of this is the same dilemma as you get with glaze materials.  That is
why in "satisfying a recipe"  you meet the need of the most difficult to
satisfy part FIRST.  And that frequently is boron, which does not come
"alone"  and whose partners generally are available in pure form.


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Originally written for Clay Art Listserv and reprinted here by kind permission of Lili Krakowski.