INSTRUCTION FOR MAKING

ETHANOL FOR FUEL

---

CHAFTER THREE

Step-By-Step Instructions For Making Ethanol

Preparation

A lot of producers use wheat, corn and milo to make ethanol. The process for

making ethanol from other crops is the same except for preparation of the raw

material. Potatoes, for instance, would have to be sliced or chopped first. If
you

are using something besides grains, you will have to experiment a little as to
how

to prepare the feedstock.

If the raw material contains sugar, not starch, the batch does not have to be

treated with enzymes. The sugar, as in sugar cane, is ready to be changed to

alcohol by the yeast without pretreatment. The batch may need to be cooked

briefly to sterilize it before adding the yeast.

Crack wheat, corn, or milo with rollers or a hammer mill grinder. It.s best to
use

rollers because fines in the mash are harder to separate from the liquid. If
using

corn, it should be screened to separate any whole kernels that escaped cracking.

Whole corn kernels are likely to plug up columns.

Making The Mash

Materials Needed - Brewers yeast from the bakery; liquefying and

saccaharifying enzymes (See appendix for suppliers); sulfuric acid diluted half

and half with water (Caution: Always add the acid to the water, not the other
way

around); lime; a little sugar; plastic bag; thermometer to read up to 212
degrees

F; pH paper; triple scale wine hydrometer that reads sugar content, potential

alcohol, and specific gravity.

Batching

Start out using 10 gallons of water per bushel of grain. You will end up with 30

gallons of water per bushel of grain. The tank size varies depending on your

application. However, for illustration purposes, we use a 4000 gallon tank.

Into a 4,000 gallon tank equipped with cooling coils and stirrer, put 1,000
gallons

of hot water, then 100 bushels of ground grain. Inject live steam and bring to
212

degrees F. Calculate how much liquefying enzyme you need. Measure out the

entire amount needed.

Add 1/5 of the liquefying enzyme you have measured out.

Boil the batch 30 minutes with stirring.



Cool to 195 degrees F. Add the rest of the liquefying enzyme measured out, and

hold the batch at 195 degrees for one hour, with stirring.

Note: Follow the instructions of your enzyme manufacturer. Take a sample and

add a drop of iodine to it. If a blue to purple color forms, the starch has not
all

been broken down. If the sample containing iodine is colorless or red-brown, all

the starch has been broken down. It is possible to break down all the starch in

this step so that it gives a negative iodine reaction. Stirring is very
important to

bring the enzyme in contact with the starch. This is probably the most difficult

step in batching.

(If all the starch has not been broken down, the saccharifying enzyme will do
it, in

time, but you run the risk of not changing all the starch in the batch to
sugar.)

Cool quickly to 140 degrees F by adding cold water to the batch. Add sulfuric

acid, diluted half with water, to bring the pH to 4.2 when tested with pH paper.
(If

you overshoot with the acid, bring the pH back up with lime.) Add the

saccharifying enzyme. Maintain the batch at 140 degrees F for 30 minutes with

stirring.

Add cold water until the temperature is about 80 degrees F. Test with the triple

scale wine hydrometer. The specific gravity should be about 1.08. Record the

potential alcohol reading for later use. if the sugar content is above 20%, add

more water. Over 20% sugar will kill the yeast.

Fermentation

Add 2 to 21/2 pounds of brewers yeast for a 3,000 gallon batch. Crumble the

yeast up in a little warm water in a plastic bag. Sprinkle in a little sugar and
mix

the yeast with your hands on the outside of the bag. As soon as the mixture

starts to bubble, the yeast is growing and should be mixed in with the batch.
(You

can grow your own yeast in a super mash)

Maintain the batch at between 80 and 90 degrees F for 21/2 days with agitation.

The tank should be covered with a pressure cap or air lock to keep the air out
but

let the carbon dioxide gas out. The fermentation itself will produce some heat.

When the yeast is producing carbon dioxide, it is making alcohol.

You can use an augur pump to mix the batch. Any pump designed for high

volume, low pressure, would be ideal.

After 21/2 days, take the potential alcohol reading on the triple scale wine

hydrometer again. Subtract this figure from the first figure obtained before

fermentation. The difference is the amount of alcohol in the batch now. The mash

should contain between 8% and 10% alcohol. If it does not, either something was

wrong in the batching, or the fermentation is not complete. If fermentation

temperature was below 80 degrees F, the yeast probably needs more time to

work. If the temperature was above 90 degrees, the yeast has stopped making

alcohol. In that case, the temperature should be brought down, more yeast added,

and fermentation continued.



All the sugar should be gone from the batch when fermentation is complete. Dip

a glucose test strip in the mash to see if any sugar is still there.

It is important to keep the air out of the batch, change temperatures quickly,
and

be clean in handling the equipment and the mash. Also, it is possible, but not

probable, that your mash may turn .sour. or make vinegar instead of alcohol.

Distillation

The cold mash is put into the boiler. The alcohol vapors are stripped out of the

mixture and carried to the top of the column.

The water, since it vaporizes at a higher temperature, is not vaporized and

continues to fall to the bottom of the column. The alcohol vapors rise in the

column and more water falls out. The vapors exit the top of the column at 170 to

175 degrees F and 190 proof.

Drying The Alcohol

The highest concentration of alcohol obtainable from a still is about 195 proof.

The final fraction of water must be removed by other means, if this is deemed

necessary. Alcohol with water can be burned in engines as is, but most experts

claim all the water has to be removed if it is mixed with gasoline. There are

conflicting claims on this.

The alcohol need not be dried if it will be used straight in a vehicle, without

mixing it with gasoline, or if it will be injected into the carburetor.

Evidence indicates that when alcohol is burned straight in an engine, the water

serves a useful function. It changes to steam in the engine and gives extra

power, and is emitted as steam through the muffler. Those using straight alcohol

prefer about 160 proof. If the alcohol will be mixed with gasoline, the accepted

method is to dry it to about 197 proof. There is no specific recipe for doing
this,

but there are several possibilities.

The alcohol can be dried by running it over zeolite, aluminum oxide or lime. The

chemical takes up the water. After use, the chemical can be dried with heat and

used again.

Measurements and Calculations

---

CHAFTER TWO

MEASUREMENT AND CALCULATIONS

This chapter is not intended to scare anyone. It is, however, a necessary evil.

The tests described below are not hard to do - most are as simple as dipping a

strip of paper in liquid and looking at the color.

We suggest you read through it without trying to absorb all of it, then refer to
it

when the test is called for in the instructions. Temperature affects the test

results. The standard temperature is 60 degrees F., but room temperature is

close enough. pH is a measure of acidity of alkalinity on a scale of 0 to 14.
The

lower the pH number, the more acid the substance. The higher the pH, the more

alkaline the solution. pH is measured by dipping a strip of pH paper into the

liquid, then comparing the color with a standard color chart supplied with the

paper. Sugar content can be read on paper strips similar to pH paper, or tested

with tablets available at wine supply shops. In both tests, the color is matched
to

a standard and the concentration read. .Tes Tape and other strips like .Clinistix.

for detecting glucose in urine are available at any drug store. Since it only
reads

up to 2% glucose, a 1 to 10 dilution should be made of the mash before using the

low range paper. A one to ten dilution is made by mixing one drop of mash with 9

drops of water in a dry container and shaking. The strip is dipped, and the
sugar

concentration reading multiplied by 10 to get the concentration in your mash.

Starch can be detected with iodine. When starch is present, a drop of iodine

added to the solution will turn it blue. This test solution should always be

discarded after the iodine is added. If no starch is present, the solution will
be

reddish-brown. This test will show whether or not there are big clumps of starch

still present during cooking, and after liquefaction, if all the starch has been

changed to sugar. Ordinary tincture of iodine from the drug store works for this

test. A sample of the mash should be diluted for the test, and the sample

containing iodine should not be returned to the mash.

Alcohol proof is measured with a Proof and Tralle hydrometer, a glass device

with a long calibrated stem. The hydrometer floats at different levels in
liquid,

depending on the liquids specific gravity (weight relative to water). The more

alcohol is mixed with the water, the less the specific gravity will be. The
alcohol

proof is read on the marked stem where it emerges from the liquid.

Alcohol potential is read on a triple scale wine hydrometer that reads specific

gravity, sugar content by weight on the Balling or Brix scale, and potential
alcohol

by volume. To determine alcohol content of fermented mash, a reading must be

made on the alcohol scale before fermentation and after fermentation. The

second reading is subtracted from the first to give the alcohol content of the

fermented mash.

Proof test - Alcohol begins to burn at 100 proof. If a little alcohol in a spoon

burns when a lighted match is passed across it, it is at least 100 proof.
Caution:



take the sample away from the still before lighting the match. The blue flame is

hard to see in a well lighted area.

Most of the equipment mentioned can be purchased at our website or at

winemaking supply shops or ordered from a laboratory supply house. Your local

hospital, clinic, or any type of laboratory can put you in touch with a
laboratory

supply company.

Enzyme Calculations

The amount of enzyme needed may be calculated on a dry starch basis (DSB)

according to the concentration recommended by the manufacturer. One bushel

of corn (56 lbs) containing 60% starch would contain 33.6 lbs starch. If the

enzyme is needed in the concentration of .1%ofDSB, multiply.001 x 33.6 to

get.0336 lbs of enzyme. If the enzyme weighs 10 lbs/gallon, divide .0336 by 10
to

get .00336 gallons of enzyme. There are 128 ounces in a gallon. So .00336 x

128 gives .43 ounces, or just less than ½ ounce per bushel of corn.

Enzymes will have different brand names, depending on the manufacturer, and

may used at different concentrations and temperatures. The enzyme supplier

will furnish recommendations for the amount of enzyme needed and its

temperature requirements. See appendix for a list of enzyme suppliers. Some

farm alcohol makers use two to three times as much enzyme as recommended

by the supplier. Use the tests at the end of each step to see if the desired
results

have been obtained. If not, the enzyme concentrations may need to be

increased. There are other enzymes available to refine the process or for
special

cases. After you become familiar with the batching, consult your enzyme

supplier about any special applications or problems. The following information

shows enzyme concentration, sample costs per bushel, and yield of alcohol and

by products.

Yeast dosage 2 pounds per 1000 gallons of mash.

1 Bushel of grain equals 56 pounds of grain.

1 Bushel of grain equals 2.8 gallons of alcohol

1 Bushel of grain equals 17 pounds of feed stock

KNOWLEDGE OF ALCOHOL

FOR FUEL

---

CHAFTER ONE

Principles of Alcohol Production For Fuel

Two types of alcohol will work equally well for fuel.

They are ethanol and methanol. we refer to ethanol

when we speak of alcohol, unless we specifically say

methanol.

Alcohol content is measured in proof. The proof is

twice the percent. Thus 100 proof alcohol is 50% alcohol

and 50% water. 200 proof alcohol is 100% alcohol.

ETHANOL

Ethanol is also called ethyl alcohol or grain alcohol. All industrial ethanol
was produced

from grain fermentation until the industry discovered they could make it cheaper
from

petroleum. This was in pre-OPEC days.

The ethanol industry was geared to producing high-purity industrial alcohol or
drinkable

alcohol. For this reason, they were locked in to using stainless steel and
copper

equipment, and also to the process of distillation. Distillation served not only
to separate

the alcohol from the water, but to separate other impurities from the alcohol -
impurities

that might make a person sick if he drank it.

That is why the fuel alcohol industry started with technology developed for the
liquor and

industrial alcohol industry. That was all the technology there was. As more
people

experiment with making alcohol strictly for fuel, ways will quickly be found to
do

it cheaper when we get away from the traditional thinking of the old distillers.
Ethanol

can be made from anything containing starch or sugar. The higher the starch or
sugar

content, the higher is the alcohol potential of the crop.

Cellulose in stalks, wood or paper can also be used to make ethanol, but the
process is

expensive with present technology.

Starch is the most important storage form of carbohydrates in the plant kingdom.

However, another significant form is inulin. Artichokes, Dahlias and Dandelions
all store

carbohydrates as inulin. The inulin is made up of fructose molecules instead of
glucose,

as in starch.

It has been found that most of the carbohydrate is stored in the Jerusalem
artichoke

stem before the bulb starts to form. If it is stored as fructose, and if it does
not change to

inulin soon after harvesting, the fructose can be fermented as is. But if it is
inulin,

we know of no commercial, economical enzymes available to break down inulin.
(Bitter

almonds do contain inulinase.) The carbohydrate can be broken down with high
heat

and strong acid, but with a lot of energy input and 20% or more destruction of
the

sugar.

If the fructose in the stem is useable, the tops can be cut off and the bulb
left in the

ground to grow again.

FERMENTATION

Enzymes break down starch into simple sugars, and yeast ferments sugars into

ethanol, giving off carbon dioxide gas as a by product. The process has been

used since civilization began. Starch is made up of long chains of glucose

molecules coiled together. The starch must be broken down into sugars that are

only one or two molecules long for the yeast to feed on.

In the process described in this book, the liquefying enzyme breaks the chemical

bonds at random inside the chain, producing shorter chains, or dextrins, as they

are called.

The saccharifying enzyme works on the end of the chain only. It could take off

the glucose molecules one by one from the ends of the starch chains and

eventually would convert all the starch to sugar. The liquefying enzyme gives
the

saccharifying enzyme more ends to work on, however, and speeds up the

process considerably.

There are other monosaccharicles (one molecule only) besides glucose, but

glucose is the most common.

Disaccharides are two monosaccharicles joined together.

Table sugar (sucrose) is one glucose and one fructose molecule.

Milk sugar, or lactose, is one galactose and one glucose joined together.

Maltose is a disaccharide made up of two glucoses.

Yeast can ferment glucose, maltose, and sucrose rapidly, and galactose and

lactose slowly.

Enzymes are proteins that change a chemical entity, or molecule, of one

substance into a molecule of something else. The enzyme acts on the

substance, but is not used up. The enzyme changes one molecule, then

detaches from it and works on another molecule. A few molecules of enzyme will

eventually get around to all the molecules of whatever it works on, but the
right

amount of enzyme will do the job faster.

People have enzymes in their mouths that break down starch. If you hold a piece

of soda cracker in your mouth, it will begin to taste sweet. This is exactly the

process that takes place in the mash. Enzymes are highly specialized. Each one

does only one thing. In this process, one enzyme chops up the long chains of

starch into shorter chains. Another enzyme changes the short chains of starch

into sugar.

Enzymes, like humans, function within a fairly narrow range of physical

conditions. They must have a certain temperature and degree of acidity. They

can be rendered useless by chemical poisons, heavy metals, high heat, etc.

Each enzyme has a certain set of conditions under which it works best.

When grain sprouts, enzymes change the starch into sugar that the new plant

can use for food. Before enzymes were avail-able for purchase, grain was



sprouted, or .malted,. then dried, ground, and mixed with the rest of the grain
as

a source of enzymes.

This method can still be used, but it is quicker to use commercially available

enzymes. Starch can be broken down without enzymes with strong acid and high

heat. However, the process takes a lot of time and energy, and then the excess

acid has to be neutralized with alkali before fermentation can take place. After

the starch is changed to sugar by enzymes, yeast changes the sugar to alcohol

in the absence of air. The process is called fermentation, and it takes about
21/2

days.

Carbon dioxide gas is produced as the yeast changes sugar to Alcohol. A bushel

of grain yields by weight about 1/3 carbon dioxide, 1/3 ethanol, and 1/3
highprotein

residue. The carbon dioxide gas can be allowed to escape through an air

lock or a one-way vent valve, or it can be collected and used.

The fermented mash contains about 10% alcohol. At this concentration, the

alcohol begins to kill the yeast. The batching should be done so that all the
sugar

and starch in the mash will have been used up by the time this10%alcohol

content is reached. It takes 13 pounds of sugar to yield 1 gallon of 190 proof

ethanol. The amount of raw material in the mash will be determined by its starch

and sugar content. In order to get fuel alcohol, the alcohol content must be

increased from 10% to 90 - 95%. At present, the only workable way to do this is

to distill it. In the future, other ways may be discovered which take advantage
of

the different properties of alcohol and water.

Distillation

The temperature of the water-alcohol mixture is raised to above the boiling
point

of ethanol (173 degrees F at sea level) but below the boiling point of water
(212

degrees F). The alcohol changes to vapor and rises in the column, but some of

the water vaporizes with it.

In a simple still, like that used by the moon shiner, the distillate is about
half

water. If this is re-distilled, a higher concentration of alcohol can be
obtained, up

to about 195 proof. Further separation cannot be obtained by distillation
because

of a quirk in the chemistry of the mixture. (Water and alcohol form an azeotrope

at this point.) The final fraction of water must be removed by other methods, if

this is necessary.

Farm alcohol plants can produce 190 to 192 proof alcohol with one pass through

a still equipped with a reflux column, which is a device for making the mixture
of

liquids vaporize, condense, then re-vaporize over and over until the alcohol is

nearly free of water.

In summary, the starch is changed to sugar by enzymes. The yeast changes the

sugar to alcohol during fermentation, giving off carbon dioxide gas and leaving
a

high-protein residue in the mash. The mash contains about 10% alcohol after

fermentation. It is then distilled to make a fuel alcohol that is 160 to 190
proof, or

80 to 95% alcohol.



After the mash has been distilled, the protein and the water are left. The water

can be reused after the protein is separated, or the entire stillage can be
flowed

over straw or hay and fed to livestock.

METHANOL

Methanol, also called methyl alcohol or wood alcohol, works just as well as

ethanol for fuel, but the process for making it is completely different.

Methanol is a highly poisonous liquid. It will kill you if you drink it, and it
can kill

you if it soaks into the skin.

Methanol is made by heating wood wastes, stalks, etc., under relatively low heat

and high pressure and then purifying the product by fractionating columns. It
can

be made from material that is not suited to ethanol production, but if grains,
for

instance were used to make methanol, all the protein would be destroyed.

Methanol can also be made from coal. Both ethanol and methanol have their

place in farm fuel plants.

Glossary Of Terms

Acidity
-
The measure of how much acid a solution contains.

Air Lock

-
A device
for keeping the air out of a fermenting

brew. Can be made by attaching a tube to the top of the
fermentation

vessel and immersing the other end of the tube in a container

of water. The carbon dioxide gas bubbles out through the water,

but air cannot enter the fermentation container. A one-way vent

valve may be used for the same purpose.

Alkalinity
-
The measure of alkali in a solution. The word

.base. is a chemical term meaning alkali.

Alcohol
-
The family name of a group of organic compounds.

Includes methanol, ethanol, isopropyl alcohol and others.

In this book, the word .alcohol. generally refers to ethanol.

Anaerobic
- Without air.
All fermentation is anaerobic.

Anhydrous
-
Literally, without water. Anhydrous alcohol

refers to 197 proof or above.

Azeotrope
- The chemical
term for two liquids that, at a certain

concentration, boil at the same temperature. Alcohol and water

cannot be separated more than 194.4 proof because at this

concentration, alcohol and water form an azeotrope and vaporize

together.

Beer
-
The fermented mash, which contains about 10%
alcohol.

BTU
- British Thermal
Unit. The quantity of heat needed to

raise one pound of water one degree Fahrenheit.

Boiling Point
-
The temperature at which a liquid boils. The

boiling point varies with the liquid and with the altitude. The

greater the altitude, the lower the boiling point.

C
- Abbreviation for
Celsius temperature.

Calibrated
-
Marked so that each mark signifies a certain

percent, proof, temperature or other measurement. For example, a

thermometer is calibrated in degrees F.

Calorie
-
The amount of heat required to raise one gram of

water one degree Celsius.

Carbohydrate
-
A chemical term describing compounds

made up of carbon, hydrogen, and oxygen. Includes all starches

and sugars.

Carbon Dioxide
-
A gas produced as a by-product of fermentation.

Chemical formula is C02. Harmless. Can be compressed

and used as a refrigerant, used in silos to exclude air and

prevent spoilage, or vented to a greenhouse to help plant
growth.

Cassava
-
A starchy root crop used for tapioca. Can be

grown on marginal croplands along the southern coast of the US.

Cellulose
- A complex
carbohydrate that gives plants their

rigid structure.

Celsius
-
A temperature scale commonly used in the sciences.

Water freezes at 0 degrees C and boils at 100 degrees C at

sea level.

Centigrade
-
The same as Celsius but now outdated.

Columns
-As used in this
book, the apparatus for separating

water from alcohol through distillation.

Compound
-
A chemical term denoting a combination of

two or more distinct elements.

Condenser
-
A cooling apparatus designed to change a vapor

to a liquid by lowering the temperature.

DDGS
-
Distillers Dried Grain Solids. The residue left
after

fermentation and distilling DDGS from corn contains about 28%

protein.

Denaturant
-
As used in this book, a liquid that makes ethanol

unfit for drinking.

Dextrose-
The same as glucose. The terms are interchangeable.

Distillate
-
The end product of distillation. For fuel, ethanol.

Distillation
-
The process of separating two liquids by

changing one to a vapor with heat and driving the vapor off the

other liquid. The separated vapor is then condensed into another

container.

Distillers Grain
-
The high-protein residue left over after

fermentation. See DDGS.

DSB
- Abbreviation for
dry starch basis.

Energy Crops
-
Crops grown for their energy potential, as

for alcohol production.

Enzymes
-
Proteins which act as catalysts to change one

chemical compound to another chemical compound. Each chemical

reaction requires a different enzyme. The enzymes are not

used up, but can be destroyed by high heat, acidity, heavy
metals

and other chemical poisons.

Ethanol
- The same as
ethyl alcohol or grain alcohol. Will

produce intoxication and can be burned as fuel.

F
- Abbreviation for
Fahrenheit temperature.

Fahrenheit
-
A temperature scale. Water freezes at 32 degrees

F and boils at 212 degrees F at sea level.

Feedstock
-
The raw material for fermentation, in this book.

Fermentation
-
The process where yeast changes sugar to

alcohol in the absence of air.

Fines
-
The fine particles that result from grinding or
cracking

solids.

Flash Point
- The
temperature at which a combustible liquid

will ignite when a f lame is introduced. Anhydrous ethanol

will f lash at 51 degrees F. 90 proof ethanol will flash at 78
degrees F.

Gasohol
- A blend of 10%
anhydrous alcohol with 90% unleaded

gasoline.

Glucose
- A simple sugar
that can be fermented to make

ethanol.

Hydrometer
-
A long stemmed glass tube with a weighted

bottom. It floats at different levels depending on the relative

weight (specific gravity) of the liquid. The specific gravity or

other information is read where the calibrated stem emerges from

the liquid.

Methanol
-
The same as methyl alcohol or wood alcohol.

Highly poisonous to drink or get on skin. Can be used as fuel.

Methane
-
A gas that can be produced from the decomposition

of organic materials or from the incomplete combustion of wood.

Membrane
-
As used in this book, a thin layer of a substance

that separates liquids by allowing one to pass through, but not
the

other.

Molecule
-
The chemical term for the smallest particle of

matter that is the same chemically as the whole mass.

Malting
-
The process of sprouting grains to produce enzymes

which break down starch into sugar.

Mash
-
The mixture prepared for fermentation.

Non-Renewable Energy
-
Energy produced from sources

that cannot be regenerated in a reasonable length of time. Oil,

coal, and nuclear energy are non-renewable energy sources.

Polysaccharides
- 30 or
more molecules of sugar joined

together.

Proof
.A
measure of alcohol content. Proof is twice the percentage

of alcohol. Thus, 200 proof is 100% alcohol.

Proof Test
-
Passing a lighted match over the alcohol to see

if it ignites. Alcohol will burn at 100 proof or above. It has
reached

.proof when it will first burn. Use test with caution.

pH
- A measure of
acidity or alkalinity on a scale of 0 to 14.

The more acid the solution, the lower the pH number. The more

alkaline, the higher the pH. Neutral is pH 7.

Pot Still
-
The type of simple still used by moon-shiners.

These have no reflux columns.

Producer Gas
-
A low BTU gas containing methane and

other gases, produced by incomplete combustion of organic
matter.

Pyrolysis-
Bring about chemical change by heating.

Rectifying Column
-
In a two column still, the second column.

Reflux
-
To return the liquid or vapor to a previous point
in

the process to be processed again. Part of the alcohol is
refluxed

through the distillation column.

Renewable Energy
-
Energy produced from renewable resources,

such as the crops grown on America.s farms.

Saccharify
-
To change to sugar.

Sight Gauge
-
A glass tube parallel to the bottom 2. of the

column used to gauge the level of liquid in the column.

Sight Window
-
The glassed-in portion of the reflux columns

that allows visual inspection of the process.

Specific Gravity
-
The ratio of the weight of any volume of

a sub stance to the same volume of water which is taken as a
standard.

Water has a specific gravity of 1.000. Different percentages

of alcohol and water will have a specific gravity of less than
1.000,

depending on the concentration of alcohol.

Starch
-
A carbohydrate made up of long, tightly coiled

chains of glucose molecules.

Starch Test
- When
iodine is added to a solution, it turns

blue if starch is present. If no starch is present, the solution
remains

colorless or turns red-brown, depending on how much iodine

is added.

Stillage
- The water and
high-protein residue left over from

distillation.

Temperature Scale
.A
scale used for temperature designations.

The Fahrenheit scale is used in this book. Another common

scale is the Celsius scale, formerly called Centigrade.

Vaporize
- To change
from a liquid or a solid to a vapor, as

in heating water to steam.

Vaporization Temperature of Ethanol
-
172.9
degrees F.

at sea level.

Vaporization Temperature of Water
- 212 degrees F. at

sea level. Less at higher elevations.

Volatile Liquid
- A
liquid that is easy to vaporize.

Wood Alcohol
- The same
as methanol or methyl alcohol.

See methanol.

Yeast
- A micro organism
that is capable of changing sugar

to alcohol by fermentation.