This article explains how at home to establish the production of butyric acid and butyl achohol by fermentation. It is divided into 4 parts.
1. Theory
2. Purification bacterial strain
3. Preparation of raw materials and its fermentation
4. Processing of fermented liquid to the required products
1. Theory
In nature, there is butyric acid fermentation caused by various types of bacteria (as a rule of Clostridia). Butyric Acid is obtained from the
condensation of two acetyl-cola molecules and accumulates in solution. Butyric acid has a very unpleasant smell resembling rotten socks, rotten
potatoes, toilet, cheese blaver and the like (depends on the tastor).
Some types of clostridium when accumulating butyric acid change their metabolism and are obtained by neutral products such as acetone, butanol, IPA
(depends on the strain). They are found in the ground, but the best source of potato peel Some straps of clostridium can produce only butyric acid
(they do not have butyraldehyde dehydrogenase and butanol dehydrogenase). Their common name is Clostridium Butyricum. Stamps capable of producing
butanol have a common name for Clostridium Acetobutylicum
When obtaining butyric acid, it is necessary to neutralize it with for example calcum carbonate. Acid medium toxic for clostridium. In this case, the
equilibrium will be shifted towards acidic extensions (obtained in the form of salts). In the production of butanol, when it accumulates in above
10-15 grams, a liter of clostridium stops life and form disputes. Clostridy belongs anaerobic. Produce spores produce that are extremely chemically
resistant. This property is based on this method isolation. Unlike yeast, they are capable of growing without access of oxygen. They are much easier
to breed and do not buy new bacteria for cooking new fermented liquid
2. Purification bacterial strain
As a source of spores of bacteria, it is best to use potatoes peel. Not every potato will go. You may have to try to one. As a cultivation
environment, you can use oatmeal. This technique Oatmeal boiled with a calculation of 60-70 grams of carbohydrates per liter of fermentation liquid in
porridge Add gram 2 per liter of Technical calcium carbonate (mixture of calcium carbonates and magnesium for better growth) Next, the peel of
potatoes peel poured with water temperature degrees 90 and keeps it for 5-10 minutes.
For the first time, it is better not to take a substrate much (in case of failure it will be hurt). After treating potatoes with water, we fill this
mixture into our cold substrate(Oatmeal) already in the fermentation container (for example, a 2 liter PET bottle). To protect our clostrid from the
air there are 2 options. Either pour with vaseline oil or sunflower oil (pasteurized) or to outweigh the gas from the bottle with gas butane for
lighters and immediately close it and attach the hydropout. I recommend the second option as oil trails will then be everywhere when using ready-made
biomaterial.
And so after all the preparations in a few days, fermentation should begin and our raw materials can float up it is normal. Now it remains only to
wait (from week to month). As fermentation, the smell changes with an unpleasant butyric acid on the smell of glue and then such a fruity (banana,
pineapple and so on). If the smell began to change to glue(butanol) and fruity. This is a success! You are isolated the desired strain
In theory, the starch raw materials can already be infected with not fully fermented liquid, but I recommend waiting for the end of fermentation and
take the liquid from the bottom of the fermentation container with the residues of the croup. There, the highest concentration of the clostridia
spore and 10-20 ml is enough for clock through 10-20 to cause began fermentation of 30 liters of fermention liquid. Further fence of culture can be
taken from the bottom of the ready-made fermented liquid or their filtrates that are further recycling.
3. Preparation of raw materials and its fermentation
Preparation of fermentation liquid to fermentation similar to the previous stage, but a little different This is done to reduce the cost and simplify
the preparation of a large number of fermented product. To begin with, we need to decide what we need. Butyric acid or butanol with acetone.
Conditions for their preparation are different. For butyric acid, we must add about 500-700 grams of Technical calcium carbonate to fermentation
liquid (technical mixture of carbonate hydroxides calcium magnium) per kilogram of carbohydrates. The permissible concentration of carbohydrates may
be probably increased up to 100 grams per liter for butyric acid fermentation. Fermentation of butyric acid goes without inhibiting full and to the
end. For fermentation butyric acid, it is also possible to use strains that did not give adhesive and ether smell (keeping some strains are produced
in addition to butyric acid very smelly products. Probably indole and skatole)
If we want to produce a butanol and acetone (some strains produce only Batanol some IPA instead of acetone), calcium carbonate need about gram 2 per
liter. Bacteria needs magnesium iron and calcium that are present in the technical calcium carbonate.
Carbohydrates need not greater than 60 grams per liter due to the fact that the produced butanol very much inhibits fermentation. Even with such a
loading at the end, fermentation is very slow.
Sugar can be used as carbohydrate raw materials.
You can use starch raw materials as black and white bread, various cereals, starch, potatoes. Before use, starch raw materials should be pouring
boiling water and hold at least 40 minutes for swelling and the destruction of microorganisms. With flour of pasta and boiled batches, fermentation
goes very quickly. Slowly with cereals of rice buckwheat. The grains slowly destroyed at the bottom of the fermentation container converting with such
a mass and rarely float up. Pea cereals and solid grain wanders very badly Potatoes cut by pieces and everything apparently does not ferment
everything.
Probably from him must be done. The larger the cereals and starch raw materials the greater you need to mess around with them.
Here is a ready technique
2 kg of old slightly molded banets were filled with 10 liters of boiling water and left 2 hours before turning into porridge. Further, this porridge
was loaded along with 700 grams of calcium carbonate and a Diluted hot water from under the tap (60 degrees) to 20 liters. Residues from the bottom of
a other fermentation container where butanol was obtained (about 100 ml of a culture sample) entered in the new fermentation container. Further, all
this is stirred, butane gas was launched in the fermentation container. The container was closed with a lid and the gauge slog was connected to the
hydraulic assembly. Fermentatiom began after 12 hours. Porridge from banets surfaced to the top. Usually this porridge dissolves under the end of
fermentation. In theory, butyric acid should be obtained as the calcium carbonate was added. Similarly, you can use any food waste After fermentaion
liqid was filtred. The sediment from the bottom of the container can be used for new fermentation. This is a biomaterial. Our bacteria that can then
use it. Can be stored up to year If you use such raw materials like sugar, then you will probably need to add a nitrogen source as urea And so when
the gases stop out, the starch raw materials (if used) was completely dissolved and an ether smell appeared (in the case of butanol. Although it also
happens at the end of butyiric acid fermentation), then fermentation is considered to be completed. Next, the stage begins to highlight products from
fermented liquid
4. Processing of fermented liquid to the required products So. After fermentation of fermented liquid, we have a solution of calcium butirate or
acetone mixture and butanol in water with any suspension. First, fermented liquid must be filtered and drained from the sludge at the bottom of the
fermentation container. You can filter through sheets or bag of stitched polypropylene. In some cases, fermented liquid on consistency is similar to
snot probably because of the granoluse or remnants of gluten with flour (definitely not clear). With such a material it is very inconvenient to work.
After filtering, the sludge leave it contains our spores bacteria Fermented liquid that we filtered should be Frozen and liquid flow from ice. In
such a concentration, there is no particular sense to mess with further processing of fermented liquid. It will be very energy consuming Fermented
liquid contains calcium butyrate mus evaporated after freezing Butanol and contaning fermented liquid must be distilled
In the case of butyric acid fermentation, it is enough to evaporate it (carefully! Strong smell), to percipate the salt and then add inorganic acid
and separated by distillation butyric acid azeotrope. Solubility of calcium butirate is about 300 grams per liter. Butyric acid always contains after
fermentation impurities of acetic acid, which must be separated In the case of Acetone, Butanol Fermented liquid needs fractional distillation after
freezing. At first, at 50-80, a mixture of acetone and water is distilled, then ethanol or IPA (depends on the strain) at 80-92 and then the butanol
azeotrope containing it is about 20% . Some strains produce only Butanol. |
