How To Create a Mash From Agricultural By-products.


1  Despite the variety, every alcohol-producing raw material belongs to one of three groups: starches, sugars, or cellulose.

1.1  Although the materials in each category are treated differently, the end product is always the same: glucose (or simple sugar), which yeast can easily convert to alcohol. The chart accompanying this section covers most of the major raw materials and how they are prepared.

1.1.1  STARCHES

All starches are converted to sugar with the help of enzymes, which are used during the cooking process1. These biochemical activators function only at the correct temperature and are destroyed by boiling.
You will also need to agitate the mash thoroughly and later in the process you'll need to maintain a full rolling boil to bring about complete conversion. If you use a high-speed mixer or a peristalsis pump to create the violent agitation, the boil can be eliminated by holding the mash at 180 deg F for 45 minutes while mixing the brew continuously.)

1.1.2  SUGARS

Sugar crops - such as sugar beets, sugar cane, and molasses, give a greater yield per acre than starch crops as a rule, because the material doesn't require conversion. Unfortunately, unrefined sugars do not keep well without a high input of refrigeration energy. Processing costs include squeezing the juice out of the stalks of plants or leaching it from their tubers.
However you extract the sugar, be sure to heat the mash until it is clean.2 the syrup to discourage contamination. Then, before you add the yeast, the sugar concentration should be adjusted to 18%3 . In addition, yeast food should be introduced along with the yeast to increase alcohol production.
Cheese whey also contains sugar (in the form of lactose) but is treated somewhat differently from the other sugars, although the end result is still ethanol.

1.1.3  CELLULOSE

America "produces" 500 million tons of cellulose waste (such as wood chips and paper-processing by-products) a year. This waste, if properly handled, could yield almost 40 billion gallons of ethanol annually. The cellulose carbohydrate is very hard to ferment, in fact, it's made virtually indestructible by a binding agent called lignin. Only in the last few years have researchers begun to develop economical methods for converting cellulose. There are successful approaches based on both enzymatic and acidic conversion. Cellulase, the enzyme that converts cellulose to glucose, was isolated by the U.S. Army in 1945. Since then, that enzyme has been improved, and though it is still relatively expensive, it will be available at reduced prices as demand increases.
Another method of converting tough cellulose fiber involves forcing cellulose pulp, at high temperature and pressure, into a short high molarity sulfuric acid bath. The acid immediately converts the cellulose to glucose, but must be removed quickly to avoid further processing and the destruction of the glucose.
Researchers at New York University and the University of Pennsylvania have developed still other methods but these are well beyond the pocketbook of a small-time operator.

2  The following chart is meant to serve as a rough guideline to mashing. If you start your own operation, you will probably discover shortcuts that will allow you to use less heat and/or enzyme powder than the chart indicates. In addition, you'll need to look into proper mash testing and fermentation procedures, as well as the best ways to handle and sell your by-products.

2.1  STARCHES

2.1.1  Wheat, Corn, Rye, Barley, Milo, Rice, Cattails

2.1.2  Pastry Waste

2.1.3  Potatoes, Cassava (Manioc), Taro

2.2  SUGARS

2.2.1  Sugar Beets, Mangel-wurzels (Fodder Beets), or Artichoke Tubers

2.2.2  Sweet Sorghum, Cane, Artichoke Stalks

2.2.3  Molasses, Sugar Products

2.2.4  Cheese Whey

2.3  CELLULOSE

Footnotes:

1The enzymes can be produced at your home by sprouting barley, and retaining the liquid. These enzymes are also called mash starter.
2Sterile solutions are not practical at home. Better to make a clean solution, by heating to 185 F. and holding at that temperature for 10 minutes
3A saccharometer can be used, but is relatively expensive. Try to get a used instrument if possible. Another device that can be adapted is a hydrometer of the sort used by diabetics to measure their urine sugar. When properly cleaned these devices can be calibrated using a variety of sugar solutions of known concentration. 
At the beginning of fermentation, the specific gravity of the mash should be about 1.080 (8 to 12% alcohol potential), while by the end of the process it will have dropped to 1.007 or less (0 to 1% alcohol potential).
Once the specific gravity has remained constant for 6 hours, you can be sure that the mash is ready for distillation.  Foe a double check to make certain complete conversion has been attained, use a standard starch test (using iodine) and a glucose test (using glucose test strips).  Both tests must be negative.
4A starting culture is made by "proofing" the same species of yeast intended for the mash with a strong solution of sugar or molasses. The "proof" will be ready in less than 24 hours. This "proof" will make an initial bolus of yeast to "kick-start" the fermentation.
5The yeast species that are used to ferment dark beers are good for molasses fermentation.

File translated from TEX by TTH, version 3.70.
On 13 Feb 2006, 09:21.