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Originally Posted by: bigwheel It gets real confusing. I was led to believe corn was not fermentable till it had been sprouted...sorta like malted barley for beer...then the local brew meister say yes corn is fermentable without sprouting. Somebody is fibbing here. Maybe the question is what has to be done to corn to make yeast like to eat it?
The answer is,
YES and NO and it depends on the path you take when fermenting corn. There are several things that must be addressed. I too had mixed understandings throughout the years. Only recently have I come to have a better understanding.
1. A dry, mature kernel of corn, that
has not been sprouted, contains a ""starch sac"" called endosperm and the embryo.
2. For the embryo to develop (germinate .... sprout), the embryo must have
food in the form of simple sugar.
3. The only way for the embryo to sprout into a plant is for the starch in the kernel to be
converted to sugar and this takes enzymes (malt).
4. Dry, mature corn (shelled or dry and still on the cob) contains no enzymes
which are required to convert starch to sugar but dry mature corn possesses the ability to make its own enzyme under proper conditions.
5. An enzyme is a protein that nature has designed. An enzyme is an organic catalyst that drastically accelerate a chemical reaction without ever being consumed during the reaction. An organic catalyst differs from an inorganic catalyst in various ways but the following sentence is only important to understand. An organic enzyme is a protein, and because a protein is
heat sensitive, not too much heat can be used when converting starch to sugar or you
WILL destroy your enzyme and conversion will immediately slow to a crawl. Hence, when converting starch to sugar, care must be taken not to exceed 150F.
The following is where ""the tree forks"" and often confuses individuals when addressing the issue of fermenting corn.
[SIZE=""4""]Let's start with fermenting cracked corn[/SIZE]
1. Cracked corn is dry, mature kernel corn that has been cracked into 6 or 8 pieces. For example ""chicken scratch"" is cracked corn.
2. The vast majority of cracked corn (by weight) is starch.
3. Starch cannot be ""eaten"" by the type of yeast we use.
4. Starch is long repeating chains of simple sugars that are connected chemically.
5. Before yeast can ""eat"" the simple sugars found in starch, the connecting chemical bonds of simple sugars that create starch must be broken in order to release all available simple sugar molecules for consumption by yeast. This is often called ""conversion"".
6. Before this converting process begins, corn (or even ground corn meal) must be gelatinized, i.e. cooked to soften the corn to a gelatin consistency. This will provide a greater surface area for enzymes to react and speed the process of conversion. It is important to note that starch
does not dissolve in water therefore starch cannot be broken down into simple sugars by simply attempting to dissolve corn meal, cracked corn, or corn starch in water (be it hot or cold).
*NOTE* Cooking corn meal alone does not convert starch to sugar. Cooking will, however, cause number and size of highly organized crystalline starch regions to decrease leading to random, unorganized crystalline regions of starch. Broken hydrogen bonds create space in the crystalline structure thus
allowing water to enter the space created by hydrolysis which in turn results in starch gelatinization. In no way has this converted polysaccharides to simple sugars but gelatinization improves the availability of starch for amylase hydrolysis (break down of available starch to simple sugar in the presence of an appropriate enzyme).
7. Once cracked corn (or corn meal) has been cooked (gelatinized) this ""gelatinous mess"" is ready for conversion.
8. As previously stated, conversion takes place in the presence of enzymes. Starches cannot be broken down to sugar without enzymes. If you choose to use grain as malt (little enzyme factories) rather than ""store bought stuff"" then you must prepare the grain and turn each kernel into an ""enzyme factory"".
9. Malt is best produced using Barley because it contains many different enzymes that will convert starch to sugar but for the sake of answering the question I will stick with corn. By soaking or wetting shelled corn for several days, each kernel will begin to swell. Soaking or wetting fools each kernel into believing that it's growing season.
10. Under the right conditions (water, warmth, and light) the miracle of life begins. Miraculously, Mother Nature devised a marvelous but complicated means for the tiny embryo to burst forth into life. Remember, I stated earlier that the tiny corn embryo needs simple sugars to develop and grow but all the sugar that's contained in the kernel is bound up as starch. The embryo cannot survive without food (simple sugar) and will surely die.
11. So, in the presence of all the right conditions, the little embryo begins to manufacture enzymes that leak into the starch sac and break down the starch to sugar so it will have the energy to grow and poke it head through the soil. Once the embryo grows into a young plant and makes it to the surface, all the starch in the kernel will have been converted and consumed and sunlight and nutrients in the soil and water will provide for the plant's remaining days on earth. The umbilical chord is severed when the plant makes it to the surface.
12. Now, what we want to do is capture the manufacture of enzymes in the kernel just at the right time thus capitalizing on the maximum enzyme level. If you wait too long, the embryo will have used all enzymes and starches to break free of its shell.
13. When little ""roots"" develop at the end of each kernel of corn (approximately 1/4"" long) enzyme levels are said to have reached the maximum level. It is at this time you wash the ""sprouting corn"", remove the little roots and ""hair"", grind the corn and toss it into your pot that contains gelatinized starch (cooked cracked corn or corn meal).
14. When the ground malt is added to your cooked corn, you will need to elevate the temperature of your mix to between 140F and 150F degrees. Conversely, if the malt is ready and you have just finished cooking the corn, then lower the temperature of the cooked corn to 140F to 150F degrees before adding the malt. Remember, enzymes are a protein and can be easily destroyed by heat.
15. After holding the mixture's temperature between 140F and 150F for 40 to 60 minutes, conversion from starch to sugar should be complete.
16. Conversion can be verified by removing a small amount of ""converted mix"" and placing it on a saucer and adding a drop of iodine. If starch is still present the sample will turn blue and the mix will require a little more heating time. If conversion is complete there will be no blue color.
17. Assuming conversion is complete, lower the temperature of the mix to around 80F degrees and toss in the yeast.
[SIZE=""3""]Fermenting sprouted corn
[/SIZE]Sprouted corn will ferment if you stop germination at the appropriate time. Remember, you want to keep the embryo from eating all the sugar that has been converted. If you allow the sprouts to get longer than the kernel of corn or greater that 1/4"", then you are losing sugar which is what the yeast needs in order to make ETOH.
When your sack(s) of corn has/have begun to sprout, wash the corn, remove roots & hair, and grind into a mush. Heat the mush for 40 to 60 minutes between 140F and 150F, cool to 80F to 85F degrees and then add yeast and allow to ferment.
*NOTE*: The reason you heat the malt and corn mix to between 140F and 150F degrees is to speed up the chemical conversion from starch to sugar in the presence of a catalyst. In theory, if you did not use heat, the reaction would still go to completion ...... but it would take much longer.
What I am about to say is purely academic and for your personal edification. With regard to organic catalyst or inorganic catalyst, I've already stated that a catalyst is used to accelerate a chemical reaction
and the catalyst is
not consumed during a chemical reaction. This means that as soon as the catalyst has been used to accelerate and complete a chemical reaction, it is released to be used again and again and again. So sometimes not much catalyst is necessary.
It should be interesting to point out that there is an unspoken truism in the above paragraph. Since a catalyst is used to accelerate a chemical reaction, then it's reasonable to assume that in the absence of a catalyst the chemical reaction will still go to completion but at a far slower rate. And this is true. Some complex chemical reactions may occur in the ""blink of an eye"" when accelerated by a catalyst but in the absence of the catalyst, the reaction may take years or even hundreds of years to go to completion.
KGB"