At what temperature does yeast die? How to properly prepare mash or the correct temperature for fermentation

Hello, dear readers of the site site. Today we will begin studying material on the most important ingredient in baking - yeast. As a result of studying this topic, you should gain an understanding of what factors influence the vital activity of baker's yeast and what techniques can be used to change the activity of yeast cells.

Yeasts and their vital functions.

In baking, yeast is used to create a porous dough structure. Yeast cells in the process of their life use the substances contained in flour nutrients and release carbon dioxide and some other metabolic products that loosen the dough and dough. It is very important to provide conditions under which the yeast will “eat” less flour and release more carbon dioxide. Therefore, the main task of the baker is to create all the necessary conditions for the yeast to actively release carbon dioxide.

To complete this task, you must have certain information about the vital functions of yeast.

In the baking industry, Saccharomycetes yeast is used to loosen the dough - sugar mushrooms ( Saccharomyces cerevisiae). In the form of pure cultures, the first Saccharomyces cerevisiae were isolated in the 70-80s of the 19th century by Hansen from the riding yeast of the Edinburgh brewery. Saccharomyces cerevisiae means Saccharomyces brewer's.

Currently the name Saccharomyces cerevisiae used to refer to various cultural forms of brewer's, baker's, spirit and wine yeast.

Saccharomyces are present in any natural starter culture used to make bread. Lactic acid bacteria are inseparable companions of Saccharomycetes. It is these microorganisms that form the basis of the normal fermentation microflora of bread dough. Complex symbiotic connections and relationships are established between Saccharomycetes and Lactobacilli in natural starters and fermented dough.

The main feature of Saccharomycetes is their ability to cause fermentation of foods containing simple sugars. Under the influence of yeast, fermentable mono and disaccharides (glucose, fructose, galactose, sucrose, maltose and some others) are produced ethanol(ethanol) and carbon dioxide. Yeast S. serevisiae do not ferment and do not absorb lactose (milk sugar), starch, fiber, pentoses.

By-products of yeast fermentation are isoamyl, isobutyl and butyl alcohols, acetaldehyde, various organic acids (lactic, succinic, tartaric, oxalic) and other substances that take part in the formation of the characteristic taste and aroma of bread.

In addition to simple sugars, the normal development of yeast requires vitamins (especially biotin), mineral salts containing potassium, phosphorus, calcium, magnesium, sulfur, etc., as well as nitrogen compounds available for absorption. The main source of nitrogen for yeast is amino acids and ammonium salts.

The influence of oxygen on the vital activity of yeast.

Saccharomyces yeasts are able to live both in the presence of oxygen and without oxygen.

In the presence of sufficient oxygen (aerobic conditions), yeast oxidizes sugars to carbon dioxide and water (respiration process).

IN general view The breathing reaction equation can be written as follows:

C 6 H 12 O 6 + 6O 2 → 6H 2 O + 6CO 2 + 2870 kJ

When there is a lack of oxygen (anaerobic conditions), yeast obtains energy by fermenting sugars (the fermentation process). The term “fermentation” was introduced in the 17th century by the Dutch alchemist Van Helmont. The fermentation of glucose, fructose and galactose is described by the following reaction equation:

C 6 H 12 O 6 → 2C 2 H 5 OH + 2CO 2 + 235 kJ

During aerobic oxidation of glucose (respiration reaction), much more energy is released than during fermentation, therefore, under conditions of sufficient oxygen access, yeast cells actively grow and multiply. As a result chemical reactions, accompanying the respiration process, a large number of various intermediate compounds are formed, thanks to which proteins, fats, vitamins and other substances necessary for their normal existence are synthesized in yeast cells.

Conditions good access oxygen is created in relatively liquid dough, so the number of yeast cells in the dough increases quickly. In a more viscous dough, the oxygen supply to the yeast deteriorates; the yeast cells switch to the anaerobic fermentation process, which significantly inhibits their reproduction.

In accordance with the given equation for the fermentation reaction, when 100 g of glucose (fructose, galactose) is fermented, about 25 liters of carbon dioxide and 51 g of ethyl alcohol are released. In the presence of oxygen (respiration), when the same amount of glucose is oxidized, carbon dioxide is released 3 times more.

For loosening the dough, carbon dioxide released during fermentation is of primary importance, and for the processes of producing alcoholic beverages, ethyl alcohol is of primary importance. In this regard, alcoholic fermentation is carried out in such a way as to limit as much as possible the access of oxygen to the fermenting product, and when preparing the dough, they try to saturate the system with oxygen as much as possible. To do this, the flour is sifted and the dough is kneaded.

The influence of temperature on the vital activity of yeast.

The temperature of the medium (dough, dough) has a significant impact on the vital activity of yeast.

At temperatures below +4 o C, the vital processes of yeast slow down sharply. Yeast cells enter a state of suspended animation. The temperature range from 0 to +4 o C is optimal for storing fresh compressed yeast.

When frozen, the viability of the yeast remains for several months. After careful thawing (at a temperature of +4 - +6 o C), the yeast can be used to prepare yeast dough. It should be borne in mind that the fermentation activity of frozen yeast gradually decreases during storage. Thawed yeast cannot be stored or re-frozen.

At temperatures above +4 o C, yeast emerges from anabiosis and begins to metabolize sugars. The higher the temperature, the more active the yeast cells become. The greatest activity of yeast is observed at temperatures from 22 to 35 o C. The temperature optimum for yeast reproduction is +25 o C.

The best lifting force of yeast is observed at temperatures close to 30 o C.

At a temperature of +35 o C the most intense alcoholic fermentation occurs. An increase in temperature from +35 o C to +40 o C is accompanied by a rapid increase in the acidity of the dough, since this temperature range is favorable for the development of acid-forming bacteria. The vital activity of yeast in the specified temperature range is still very intense.

Temperatures around +40 o C have a depressing effect on the vital activity of yeast.

At 45 o C, gas formation caused by yeast cells decreases sharply, but thermophilic bacteria continue to actively develop up to 54 o C.

When the temperature rises to 45-50 o C, mass death of yeast begins.

At 60 o C the vital activity of yeast practically stops.

Saccharomyces yeast is capable of forming spores under unfavorable conditions, but when temperatures reach 70 o C, even yeast spores die.

The temperature of the inner layers of the crumb during the baking process of bread reaches 96-98 o C. At this temperature, the normal yeast microflora almost completely dies.

Yeast dough is usually prepared in the temperature range from 26 to 30 o C. In this range, amylases intensively break down starch into sugars, and yeast vigorously ferments sugars, releasing carbon dioxide. Increasing the temperature to 35-40 o C accelerates the process of gas formation, however, the rheological properties of the dough at elevated temperatures noticeably deteriorate.

A temperature of 30 o C is a compromise between the speed of the fermentation process and the quality of the dough. At 25 o C, the quality of the dough improves, but the speed of the fermentation process slows down; at 35 o C, the fermentation speed increases, but the quality of the dough (and finished products) gets worse. Elevated temperatures cause the gluten to weaken, the dough becomes more liquefied, the elasticity of the dough decreases, and its dimensional stability deteriorates. Therefore, higher temperatures are suitable for processing flour with strong gluten, and lower temperatures for processing flour with weak gluten.

Keep in mind that there are some differences in how different strains of yeast react to changes in temperature. In addition, the composition of the dough and the presence of certain additives in it can improve or worsen the resistance of yeast to high or low temperatures. For example, ethyl alcohol formed during fermentation reduces the resistance of yeast to heat, powdered milk increases the resistance of yeast to low temperatures, etc.

The influence of dough recipe and humidity on the vital activity of yeast.

Every baker should know that individual dough recipe components can have a depressing or activating effect on the vital activity of yeast.

Small additions of sugar activate yeast, but increasing the sugar content to 15% or higher inhibits their vital activity. When producing high-precision baked goods, it is better to use special (osmotolerant) yeast, which is less sensitive to high concentrations of sugar.

The inclusion of flour brew, amylolytic enzymes, malt, and some mineral additives (ammonium salts, phosphorus, calcium, potassium, magnesium, etc., approved for use as food additives) in the dough recipe has an activating effect on the vital activity of yeast.

Inhibits the activity of yeast: table salt (in a concentration of more than 1-1.5%), ethyl alcohol (in a concentration of more than 2-5%), egg white and yolk, refined vegetable oil(at a concentration of more than 2.5%), butter, preservatives and some other ingredients used in the production of bread.

Yeasts are moisture-loving organisms (hydrophytes). In a situation of sharply limited access to water, yeast reduces its activity, and in a state of varying degrees of dehydration, it enters suspended animation. Techniques of varying degrees of dehydration are used in the production of commercial yeast with a longer shelf life.

The higher the humidity of the nutrient medium, the more actively the yeast microflora develops and the more intense fermentation occurs.

To intensify the vital activity of yeast, the sponge dough method is used. Doughs are prepared with a thinner consistency than dough. In addition, the dough recipe includes only those components that are necessary for the life of yeast (water, flour, sugar and in some cases special nutritional additives), and salt, baking and other ingredients that inhibit the development of yeast are added directly to the dough.

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Alcoholic fermentation is the basis for the preparation of any alcoholic drink. This is the simplest and affordable way get ethyl alcohol. The second method, ethylene hydration, is synthetic and is rarely used and only in the production of vodka. We'll look at the specifics and conditions of fermentation to better understand how sugar turns into alcohol. From a practical point of view, this knowledge will help create an optimal environment for yeast - correctly placing mash, wine or beer.

Alcoholic fermentation is the process of yeast converting glucose into ethyl alcohol and carbon dioxide in an anaerobic (oxygen-free) environment. The equation is as follows:

C6H12O6 → 2C2H5OH + 2CO2.

As a result, one molecule of glucose is converted into 2 molecules of ethyl alcohol and 2 molecules of carbon dioxide. In this case, energy is released, which leads to a slight increase in the temperature of the environment. Also, during the fermentation process, fusel oils are formed: butyl, amyl, isoamyl, isobutyl and other alcohols, which are by-products of amino acid metabolism. In many ways, fusel oils form the aroma and taste of the drink, but most of them are harmful to the human body, so manufacturers try to remove harmful fusel oils from alcohol, but leave the beneficial ones.

Yeast are unicellular spherical fungi (about 1,500 species), actively developing in a liquid or semi-liquid medium rich in sugars: on the surface of fruits and leaves, in the nectar of flowers, dead phytomass and even soil.

These are one of the very first organisms “tamed” by humans; yeast is mainly used for baking bread and making alcoholic beverages. Archaeologists have established that the ancient Egyptians 6000 BC. e. learned to make beer, and by 1200 BC. e. mastered baking yeast bread.

Scientific research into the nature of fermentation began in the 19th century; J. Gay-Lussac and A. Lavoisier were the first to propose the chemical formula, but the essence of the process remained unclear, and two theories arose. The German scientist Justus von Liebig assumed that fermentation is of a mechanical nature - vibrations of the molecules of living organisms are transmitted to sugar, which is broken down into alcohol and carbon dioxide. In turn, Louis Pasteur believed that the fermentation process is based on biological nature - when certain conditions are reached, yeast begins to convert sugar into alcohol. Pasteur managed to prove his hypothesis experimentally; later other scientists confirmed the biological nature of fermentation.

The Russian word “yeast” comes from the Old Church Slavonic verb “drozgati”, which means “to press” or “to knead”, and there is a clear connection with bread baking. In turn, the English name for yeast “yeast” comes from the Old English words “gist” and “gyst”, which mean “foam”, “to produce gas” and “to boil”, which is closer to distillation.

The raw materials for alcohol are sugar, sugar-containing products (mainly fruits and berries), as well as starch-containing raw materials: grain and potatoes. The problem is that yeast cannot ferment starch, so you first need to break it down into simple sugars, this is done by the enzyme amylase. Amylase is found in malt, a sprouted grain, and is activated at high temperatures (usually 60-72 °C), and the process of converting starch to simple sugars is called “saccharification.” Saccharification with malt (“hot”) can be replaced by the addition of synthetic enzymes, in which there is no need to heat the wort, which is why the method is called “cold” saccharification.

Fermentation conditions

The development of yeast and the course of fermentation are influenced by the following factors: sugar concentration, temperature and light, acidity of the environment and the presence of trace elements, alcohol content, oxygen access.

1. Sugar concentration. For most yeast races, the optimal sugar content of the wort is 10-15%. At concentrations above 20%, fermentation weakens, and at 30-35% it is almost guaranteed to stop, since sugar becomes a preservative that prevents the yeast from working.

Interestingly, when the sugar content of the medium is below 10%, fermentation also proceeds weakly, but before sweetening the wort, you need to remember the maximum concentration of alcohol (4th point) obtained during fermentation.

2. Temperature and light. For most yeast strains, the optimal fermentation temperature is 20-26 °C (bottom-fermenting brewer's yeast requires 5-10 °C). The permissible range is 18-30 °C. With more low temperatures Fermentation slows down significantly, and at values ​​​​below zero, the process stops and the yeast “falls asleep” - falls into suspended animation. To restart fermentation, it is enough to raise the temperature.

Too high a temperature kills the yeast. The stamina threshold depends on the strain. In general, values ​​above 30-32 °C are considered dangerous (especially for wine and beer), however, there are certain races of alcohol yeast that can withstand wort temperatures up to 60 °C. If the yeast is “cooked”, you will have to add a new batch to the wort to resume fermentation.

The fermentation process itself causes an increase in temperature by several degrees - the larger the volume of wort and the more active the yeast is, the stronger the heating. In practice, temperature correction is done if the volume is more than 20 liters - it is enough to keep the temperature below 3-4 degrees from the upper limit.

The container is left in a dark place or covered with a thick cloth. The absence of direct sunlight allows you to avoid overheating and has a positive effect on the work of yeast - fungi do not like sunlight.

3. Acidity of the environment and the presence of trace elements. An acidic environment of 4.0-4.5 pH promotes alcoholic fermentation and suppresses the development of third-party microorganisms. In an alkaline environment, glycerol and acetic acid are released. In neutral wort, fermentation proceeds normally, but pathogenic bacteria actively develop. The acidity of the wort is adjusted before adding yeast. Often, amateur distillers increase the acidity with citric acid or any sour juice, and to reduce it, they quench the wort with chalk or dilute it with water.

In addition to sugar and water, yeast requires other substances - primarily nitrogen, phosphorus and vitamins. Yeast uses these microelements for the synthesis of amino acids that make up their protein, as well as for reproduction initial stage fermentation. The problem is that at home it is impossible to accurately determine the concentration of substances, and excess acceptable values may negatively affect the taste of the drink (especially wine). Therefore, it is assumed that starchy and fruit raw materials initially contain the required amount of vitamins, nitrogen and phosphorus. Usually only pure sugar mash is fed.

4. Alcohol content. On the one hand, ethyl alcohol is a waste product of yeast, on the other hand, it is a strong toxin for yeast fungi. When the alcohol concentration in the wort is 3-4%, fermentation slows down, ethanol begins to inhibit the development of yeast, at 7-8% the yeast no longer reproduces, and at 10-14% it stops processing sugar - fermentation stops. Only certain strains of cultured yeast, bred in laboratory conditions, are tolerant of alcohol concentrations above 14% (some continue to ferment even at 18% or higher). From 1% sugar in the wort, about 0.6% alcohol is obtained. This means that to obtain 12% alcohol, a solution containing 20% ​​sugar is required (20 × 0.6 = 12).

5. Access to oxygen. In an anaerobic environment (no oxygen), yeast is focused on survival rather than reproduction. It is in this state that maximum alcohol is released, so in most cases it is necessary to protect the wort from air access and at the same time organize the removal of carbon dioxide from the container in order to avoid high blood pressure. This problem is solved by installing a water seal.

With constant contact of the wort with air, there is a danger of souring. At the very beginning, when fermentation is active, the released carbon dioxide pushes air away from the surface of the wort. But at the end, when fermentation weakens and less and less carbon dioxide appears, air enters an unclosed container with wort. Under the influence of oxygen, acetic acid bacteria are activated, which begin to process ethyl alcohol into acetic acid and water, which leads to spoilage of wine, a decrease in the yield of moonshine and the appearance of a sour taste in drinks. This is why it is so important to close the container with a water seal.

However, to multiply yeast (achieve its optimal quantity) oxygen is required. Usually, the concentration found in the water is sufficient, but for accelerated propagation, after adding the yeast, the mash is left open for several hours (with access to air) and stirred several times.

How long does the mash ferment and what does it depend on?

In my practice, the mash ripened over time intervals from 4-5 to 60-70 days. Yes, yes, don’t be surprised - this is a unique case when in the fall I collected plum carrion - about 40 kg, peeled it, mashed it, added a little water and forgot about it for 2 months. At the same time, she stood in the basement at a temperature of about +7 ... +12 C o. Many will now say - it’s nonsense, it’s lost! And I will say - the pipes, not only survived, but also magnificently fermented into alcohol due to natural yeast - I did not add them to this mash.

So what does the fermentation rate depend on? Let's look at all these factors point by point:

• External conditions - temperature and rest. I never tire of repeating that mash is alive, and therefore it requires appropriate handling. Not only temperature, the optimal range of which is +22… +28 C o, affects the intensity and speed of fermentation, but also rest. Remember when mom or grandma sets the dough to rise, she puts it in a warm room and asks not to run there? Vibrations can “scare off” the yeast, and the dough may fall. So is the mash - ideally it should be in a quiet and dark place. That’s why in my basement, even at the lowest temperature, it completely fermented without adding yeast or sugar, albeit over a long period of time, like wine
• Chemical composition - we are talking here about both the quality of water and the type of raw materials. For example, fruit mashes ferment faster than cereal mashes, since the sugars in them are more easily accessible to yeast. And to stimulate good fermentation of pure sugar mash, I use a little secret, which in the summer allows me to achieve optimal carbonation of homemade kvass, which I also desire myself. I add some raisins to it. For 20 liters of mash, 50 grams of raisins are enough. The microelements contained in it are a natural feed for yeast, so fermentation proceeds more actively
• Type of container - remember - never, under any circumstances, use containers made of non-food metals to prepare mash! In such a container it does not turn sour, but is filled with metal oxide, acquiring a disgusting taste - this is mine personal experience, and I didn’t even bother distilling such mash. Optimal types containers - glass, food grade stainless steel, aluminum, copper. These types of metals interact very weakly, and glass does not interact with liquids at all. Food-grade plastic is also suitable, but is at least preferable to glass

How to achieve optimal results and what to focus on?

Optimal fermentation times for mash

If we do not take into account exceptional cases, my mash, regardless of its composition, ferments on average 8-10 days. Pure sugar mash ferments about the same amount at the proportions of 1 kg of sugar per 3 liters of water and 50 grams of live baker's yeast. In principle, it can be distilled (especially summer wine) already on the 7th or 8th day, but I try to achieve maximum yield. Most often I drive from what grows in the garden, and in my case it is plum, apple, quince, pear, apricot and grapes. Yes, yes, quince is added solely for the sake of flavor, since its yield is small. Most of all I have plums, so my mash is often made from it. I prepare mash as follows:

• I collect carrion - fallen fruits
• I clean the seeds (if I’m not too lazy)
• I load it into a forty-liter aluminum flask (aka my still) and press it into a puree.
• For 15-20 kg of pulp I add about 15 liters of water
• I add to this volume 2 kg of sugar and 100 grams of baker's yeast
• Mix well and place under a water seal
• I let it ferment for 8-10 days - during this time the fermentation process at a temperature of +25 C o completely stops

And then, attention! I take out the silicone tube from the water bottle, which acts as a water seal, and place the flask on the gas burner. Yes, yes, without pulp separation, without clarification - just gas! And I connect the pipe to the refrigerator through my homemade steamer. Nothing burns for me, everything distills perfectly, and I talked in detail about how I distill mash into moonshine in another article.

When I prepare a mash for whiskey, and its main component is corn grits, I let it ferment for at least 14 days! I will say more, you can safely leave it for 17-20 days - the main thing is that the water seal and container are airtight. Even after boiling into wort, corn starch is quite difficult to process by yeast (both baker's and wine-alcohol yeast). Therefore, 15 days is the optimal period during which the sugars will be completely processed and the aroma will be revealed properly.

Many people prepare alcohol at home. Making mash? an important matter that requires vigilance, attentiveness and scrupulousness. You will spend time and effort, but you will gain experience, an exciting activity and a finished, high-quality homemade product. It is important to observe the subtleties: fermentation temperature and recipe. The result will not be long in coming.

Yeast? These are microorganisms, or more precisely, fungi. They live in water and eat sugar. During the reproduction process, they release heat, carbon dioxide and alcohol. With their help, home craftsmen prepare moonshine.

Temperature indicators: the importance of following technological processes

Fermentation temperature? This is an indicator that must be followed with all rigor. By average standards, the norm is 24-30°C. But in this case, the need for yeast in future moonshine cannot be discounted. It should be noted at what temperature they will begin to ferment. Only in this case will they emit heat. And this? the determining factor in the preparation of mash.

As soon as the yeast starts working, the mash will heat itself. Overheat? an unacceptable oversight that would jeopardize the entire operation. It is important that during fermentation, the thermometer does not show a reading higher than 40°C. Once the temperature reaches a dangerous level, the yeast will die. There will be nothing to distill the moonshine from and everything will have to start all over again.

How to hurry? mash? Speeding up fermentation

Thermometer and thermostat. Features of operation in distillation

During the fermentation process, you need to prepare the necessary technological attributes that will help distill mash into moonshine. What is the temperature at this stage? the most important indicator that cannot be ignored. To maintain it, you will need a thermometer.

The thermometer measures the temperature inside the still cube. You need a mercury unit with a scale of up to 120 0 C. As a rule, we are talking about a glass device, with which you need to be extremely careful.

If it is logistically possible, you can mount a bimetallic thermometer. A multimeter will also be suitable for our purposes. These devices can be used to determine the exact temperature at the moonshine distillation stage. They make it possible to determine the exact time of collection of a high-quality product.

By thermostat we mean a unit that allows you to maintain a stable temperature in a container with mash. The power of this device directly depends on the volume of the vessel with mash. If the barrel contains up to 50 liters, buy a unit with a power of at least 100 W. The operation of this unit is cyclical, so it does not require a lot of electricity.

Please note that the feedstock is mostly heated from above. So that the temperature regime is uniform throughout the entire volume, the mash you need to stir from time to time.

The thermostat is easy to install. You don't need to make holes to attach it. Bend the wire over the edge so that the body of the device is dipped into the mash. There must only be a sensor on the surface so that the temperature can be monitored. Press the unit wire with the cover, but do it very carefully so as not to damage the wire. It is important not to twist the wire to avoid breaking it.

The importance of temperature

Each moonshine has a completely unique taste. The secret of this uniqueness lies in the original recipe of each individual mash.

In the classical sense, mash is prepared according to the following canons.

Distillation or cooking temperature

When the mash reaches a temperature of 65°C, light harmful fractions evaporate. The resulting moonshine is called “pervak”. Experts say that it’s a first? this is a dangerous poison. It must be collected in a separate container and disposed of or used for technical needs.

Until the temperature reaches 63°C, the future moonshine is heated and boiled over the highest heat. Then the heating speed is sharply reduced to slowly reach 65-68°C. If this is not done, the hot mash will flow into the refrigeration part of the unit. The color of the drink will be fusel. The quality will decrease. The situation can only be improved by re-distillation.

Gradually the distillation temperature of the mash will increase, and the intensity with which moonshine is distilled, ? fall. The collection of moonshine is stopped when the mixture heats up to 85°C. From this moment, fusel oils begin to evaporate, making the moonshine cloudy and deteriorating its quality.

When?first? comes out, you should substitute a container to collect the moonshine. Gradually increase the heater power. This is necessary for the mash to reach a new temperature - 78°C. After a while, the main product will begin to be released.

Once the temperature has reached 85°C, the distillate is collected in a new vessel. The so-called?tails? add to a new portion of mash to increase the strength.

The quality of moonshine depends more than half on water. Many beginners think that there is nothing complicated in choosing water; just pour in any available water. But experienced moonshiners approach this process with all responsibility, paying attention not only to temperature, but also to the quality of the water itself. Otherwise, the mash may not ferment or the taste of the finished moonshine will be unpleasantly surprising.

Water requirements for mash:

1. Hygienic standards. The water used for moonshine must be clear, without foreign odor (taste) and meet the standards for drinking water. This is a standard, but at the same time the most important requirement.

2. Stiffness. Water hardness is the totality of its physical and chemical properties associated with the content of alkaline earth metal salts (mainly potassium and magnesium). Too high hardness inhibits fermentation, while low hardness prevents yeast from developing normally, since soft water does not have a sufficient amount of microelements.

Unfortunately, it is not easy to find out the degree of water hardness, since this indicator is measured in a laboratory. For mash, you need water of medium hardness - 2-10°Zh according to the national standard of the Russian Federation (GOST R 52029-2003).

First, yeast bacteria actively multiply, and after oxygen is pumped in, they begin to process sugar into alcohol. In turn, distillation removes from the water almost all the necessary microelements, which, in addition to sugar, feed beneficial microorganisms.

Water for mash should be spring water (from a well) or tap water. Before preparing moonshine, I recommend letting the selected water sit for 12-24 hours so that all harmful impurities (primarily chlorine and heavy metals) sink to the bottom. Water can also be purified by passing it through special filters.

Tap water is fine too

Water temperature for mash

Yeast is added to water heated to 20-30°C. Considered optimal for mash temperature 23-28°C which should be constantly maintained. At lower values, fermentation slows down, and when it drops to 18°C ​​and below, it may stop altogether. Therefore, in the cold season, it is often necessary to heat the mash with aquarium heaters or other devices.

In water that is too hot (above 30°C), most yeast bacteria die before they can do any good. During active fermentation, the temperature of the mash independently increases by several degrees (relevant for containers with a volume of 20 liters or more), so sometimes moonshiners have to cool the mash.

All of the above tips are relevant for any mash recipe, regardless of the raw materials and cooking technology. Poor quality water worsens the taste and reduces the yield of moonshine.

Yeast is a fairly popular product and is often used in a variety of products that people consume every day. Many probably believe that they are found only in bread, buns and other similar products. However, in fact, the range of their use is much wider than it seems to the average person; they can be: in wine, beer, alcohol, moonshine. But if the product is used incorrectly, namely if it is overheated, the yeast will die. At what temperature this happens, not every person knows.

bread yeast

There is a fairly large number of yeasts that are used for baking bread, they all differ in their structure and living conditions. In most cases, housewives use fresh or dry yeast, but there are also granular and fast-acting ones. They all have different effects on baking and there is a certain temperature, after which they stop working. Therefore, it is extremely important to know at what temperature yeast dies so that flour products are not spoiled.

Fresh yeast

This is the most popular type of product for baking bread. In most cases, they are sold in small cubes of 50 or 100 g. Thanks to this yeast, baked goods have the perfect color and have a pleasant texture.

It is believed that such a product causes the strongest fermentation, due to which the baked goods are fluffy and do not have a strong specific odor. The moisture content of this yeast is 70%.

This product is preserved quite well. It is worth noting that fresh yeast can be stored in the refrigerator for up to twelve days. Storage temperature should be no higher than 10 degrees, recommended 0...4 °C.

At what temperature does yeast in bread die?

Carrying out many experiments, scientists have proven that when bread or other flour products are baked, the yeast is not destroyed, they remain in the product, only they are overgrown with gluten capsules.

It is worth noting that even at high temperatures, fungi cannot be completely destroyed; they can withstand up to 500 degrees. However, this only applies to thermophilic yeast. They also cause quite a lot of harm to the body. In the finished product, in 1 cubic centimeter there are more than 120 million yeast cells that survived after baking.

All of them negatively affect health; when fungi reach a person, they begin to actively develop. Due to this, active destruction of cells occurs, which leads to the fairly frequent formation of benign and sometimes malignant tumors.

As for ordinary live yeast, the situation here is completely different. When baking flour products, a temperature of approximately 95...98 degrees is formed inside the crumb. Ordinary yeast cannot withstand such temperatures and simply die, leaving only a small percentage of the fungus, which practically does not cause any harm to human health.

Brewer's yeast

The optimal temperature for yeast to function in beer is approximately 32 °C. But at what temperature does brewer's yeast die? In this case, they are very heat-resistant; they are completely destroyed when the degree in their habitat rises above 38 units.

It is worth separately noting the fact that brewers do not infuse their product at the optimal temperature for yeast, 32 degrees. The thing is that at 32 °C this product actively produces fermentation, due to which a very large number of complex substances appear, and they have a very unpleasant odor. At the optimal temperature, a large amount of acetaldehyde is produced, due to which the beer becomes undrinkable (a very pungent and unpleasant odor).

Alcoholic yeast

This type of yeast is quite tenacious and has a very wide temperature range suitable for its life. Not everyone knows at what temperature alcohol yeasts die; it is about 50 degrees; only after this mark is passed, the production of alcohol becomes impossible.

For this product to function normally, the temperature of its environment should be about 29...30 degrees. This is considered the ideal temperature. However, they can also develop at temperatures from +5 to +38 °C. In the range between 38 and 50 degrees, the yeast is still alive, but it simply stops its activity; if the degree drops, it will become active again and will perform its function. Therefore, it is highly advisable to observe the temperature regime so that the quality of the alcohol is not extremely low.

Conclusion

A large number of people encounter products that would not be made if simple microorganisms such as yeast did not exist. Therefore, it is extremely important to know when yeast dies, at what temperature it can exist, and when it simply suspends its vital activity.

In most cases, baking yeast survives at a temperature of 42...48 degrees; if this indicator is exceeded, it does not continue to exist. If a person makes wine, then he should know that for normal fermentation the temperature should be 26...30 degrees, and when it goes beyond 34 degrees, the yeast dies.

The same applies to brewer's yeast, only in this case it survives at temperatures up to 38 degrees and is more stable.

It is worth mentioning thermophilic yeast separately; they are very harmful to the human body, so it is highly advisable to simply exclude products made with such an ingredient from your diet. In most cases, this product can be found in bread and pastries, which are produced industrially and have a very low cost compared to other products in the same category.

Temperature is one of the main factors in proper moonshine brewing. Chemical reactions occurring in the mash will be slowed down or will not begin at all if you do not prepare for them optimal conditions. What temperatures are we talking about and how to maintain them correctly?

Note that rarely any reaction requires a strictly defined temperature. Typically, a spread of several degrees is assumed, for example, from 18 to 28, at which the chemical reaction proceeds qualitatively. Not everyone has laboratories at home with a bunch of thermometers, so average values ​​are taken as a basis, which can be easily maintained at home.

To measure the temperature of the mash, use a thermometer with a probe

The generally accepted indicator is temperature from 20 to 30 degrees Celsius. When such conditions are maintained, yeast of almost all types will actively work. When using baker's, dry, alcohol, wine, beer or turbo yeast, this thermal environment will be optimal.

“Cooking” yeast is much easier than “freezing” it. So try to contain the heat rather than give it in.

• At a temperature below +5 degrees, any type of yeast will die. If you accidentally froze the mash, then you need to warm it up and add the fungi again.
• From +5 to +20 the yeast exhibits extremely low activity, but continues to live. They are in a kind of hibernation. When the temperature rises, they wake up, and when the temperature drops, they die.
• From +20 to +30 you will achieve maximum fermentation efficiency. This is an ideal to strive for.
• From +30 to +42 you risk ruining the mash. The point is that the temperature environment lower than in the fermentation tank. When the process is too active, a lot of heat is released and the fungi may not withstand such “heat”.
• When increasing more than +42 degrees, all the yeast that is used in the fermentation of the mash dies. It seems that achieving such boiling water is very difficult, but in practice it is a common occurrence.

It's safer to keep the temperature a little lower. No one can say 100% how the mash will behave in a given situation.

If it “plays” very actively, then due to the heat generated, the liquid can heat up and destroy all the beneficial fungi. It is very difficult to bring it to +5, but to +50 without problems.

At what fermentation temperature is more moonshine produced?

An interesting study was carried out by measuring the efficiency of fermentation and the release of harmful substances at different temperatures. It turned out that when 30 degrees Fermentation proceeds 4 times faster, and the amount of fusel oils formed is 4 times less. The alcohol emission in this case is 10% less.

At 20 degrees"exhaust" produces more alcohol, but the mash costs longer. More harmful substances are also produced. Double distillation with separation of fractions completely solves the issue of the quality of moonshine, so if quantity is more important than speed for you, then it is better to keep fermentation at the minimum permissible temperature.

The results of the study are presented in the photo below.

What devices can maintain the optimal temperature of the mash?

There are no specialized solutions yet, so we will use the ingenuity and experience of other moonshiners. Below we will describe the three most well-known methods that will help you preserve the contents of the fermentation tank under certain conditions.

Just don't laugh, it really works effectively. We set the required degrees, lower it to the bottom of the fermentation tank and monitor the temperature of the mash itself. It will be slightly higher due to active chemical reactions, so it is better to reduce the power by 2-3 degrees.

Price from 300 to 1500 rubles. You can order on AliExpress or buy at a pet store.

Aquarium water heater with thermostat

Heating pad for belt

The operating principle is as follows: we wrap the heating pad around the fermentation tank, set the required degrees and turn it on. In a cold room, it may not solve the whole problem, but its effect will be 100%.

The price is about 1000 rubles.

Heated mat

In this case, the fermentation tank is simply placed on a heated place and the heat comes from the floor. Considering that cold sinks and heat rises, heating the liquid from below is a very correct solution.

Price from 1000 to 1500 rubles.

Millions of people prefer to make alcohol at home. Of course, making mash is an incredibly exciting activity. But before you start the process, you need to know all the nuances: what it is made from, what the temperature should be during fermentation, what recipe will be best, how moonshine is distilled and much more. All this is important if you want to get excellent results.

Initial products. What do we need

However, many lovers of homemade alcohol stick to the classic recipe. To bring it to life, you need to follow all the stages and nuances:

• First, prepare the yeast. To do this, take half a liter of warm water (about 30-40 degrees, no more). 100 grams of sugar are added to it. Yeast is already mixed into the resulting solution, based on the method of application. Leave the resulting mixture for 2 hours in a warm place where the temperature is at least 30 degrees. The product should be stirred periodically. As soon as foam begins to actively form, it is time to continue preparing the mash.
• You need to prepare the wort. To do this, you need to dissolve a kilogram of sugar in 4 liters of water. The temperature should be room temperature or slightly higher.
• The yeast is poured into the wort. The ideal situation is if the temperature of both the yeast solution and the prepared wort is the same. In extreme cases, it may differ only by 1-2 degrees. Everything is thoroughly mixed and left to ferment. The optimal temperature is 20-35 degrees.

The temperature regime must be strictly followed. On average it is about 24-30 degrees. However, each yeast has its own needs. Therefore, it is worth clarifying at what temperature they begin to actively “work”. Only in this case will the yeast produce heat, which is important for mash. After all, in this case, she will be able to warm herself up.

It is important to prevent overheating. Therefore, during fermentation, the temperature should not exceed 40 degrees. Then the yeast will simply die, and no moonshine will result. The process will simply stop. When is everything ready?

The readiness of the mash is indicated by such signs as:

• There is no release of carbon dioxide, fermentation stops;
• On top the product becomes light and transparent, because... “spent” yeast begins to sink to the bottom;
• If you taste the mash, it will be sour and bitter. There is no sweetness in it, but there is alcohol;
• When measuring sugar levels with a special device, the indicator will be at level 0.