How to prepare beer wort. All about Temperature Pauses in Brewing: Acid and Protein Pause and Enzymes

That a novice brewer will have to face the lack of certain knowledge and skills. Unfortunately, this is true, since one cannot do without knowledge of how some biochemical processes proceed. These processes occur as a result of malting and mashing malt, this is the most time-consuming and difficult stage in the preparation of beer. Before moving on to describing mashing, it is necessary to familiarize yourself with a few more terms that are used in brewing - "grain malting", "malt modification" and "temperature rests".

Running a little ahead, I note that the use of highly modified malt made it possible to nullify the maintenance of certain temperature pauses and the use of one-step mashing. However, it will be very useful to be familiar with the science of temperature pauses and multi-step technology.

Grain malting

Malting plays the most important role in brewing. What is sostoyanie? This is just the process of germinating the grain, followed by drying, in order to stop the germination. As a result of grain germination, enzymes are formed, but it is more important to note a number of processes that take place at this moment. Firstly, protein breakdown occurs, the wort is saturated with amino acids that are necessary for yeast growth, as a result, future beer becomes more biologically stable. Secondly, glucans are broken down. It is the degree of breakdown of proteins and glucans that is called malt modification.

If you buy malt in online stores, I recommend that you take an interest in the modification, 98% of the malt will be highly modified, which greatly simplifies our lives.

Enzymes

What are these enzymes that are formed as a result of malting? Enzymes are nothing more than proteins, which in turn are high-molecular organic substances consisting of alpha-amino acids connected in a chain by a peptide bond. These long chains come in various shapes (we won't go into depth) that break easily when temperature or pH changes. During mashing, the protein and carbohydrate chains that bind the fermentable sugars are broken. In addition, as a result of heating starchy substances, they become more soluble.

Exposure of temperature pauses is necessary for denaturation. As a result of the destruction of the enzyme by an increase in temperature, it denatures over time, that is, it is completely destroyed and cannot return to its current state.

Different enzymes have their own temperature threshold for denaturation, therefore, during the mashing process, different temperature pauses are maintained.

Below I will give a table of correspondence of denaturation temperatures for various enzymes.

Temperature pauses

Phytase or acid pause

During the phytase pause, a decrease in the pH of the mash occurs, as a result of the destruction of the phytin molecule by the phytase enzyme and the release of phytic acid. The optimum temperature for an acid pause is 35-50 degrees.

This pause is most often ignored by brewers for a number of reasons - there are simpler ways to influence the pH of the mash and the duration of the pause (it takes 50-60 minutes for the pH to change).

Glucans are also destroyed, which turn the mash into a paste. Beta-glucans are carbohydrates that are broken down by the enzyme beta-glucanase.

Beta-clucanes do not show up in highly modified malts, however, if cloudiness is observed, then it is worth sustaining a 20-minute acid pause.

It should be noted that on some resources, the beta-glucanase pause is considered as a separate one, on others it is combined with the acid pause, since they have the same temperature range. But beta-glucans are broken down faster.

Protein pause

The temperature range of the protein pause lies within 45-55 degrees. At such temperatures, two enzymes, proteinase and peptidase, work. Proteinase acts on proteins of long chain amino acids, splitting them to medium length. Peptidase also acts on terminal proteins. The optimal temperature for the work of these proteins is different, it is difficult to maintain the ideal temperature for each, so I prefer the optimal temperature barrier for one of the enzymes.

Most often, the temperature for proteinase is maintained at 55 degrees for 20-30 minutes. As a result of this pause, our beer becomes more stable.

Important! Low temperature pauses are most effective for thick mashes, and the effect of low temperature pauses can also be improved by stirring.

Saccharification

Sometimes this pause, like the first one, is divided into two, or rather, the maltose pause is considered separately from the alpha-amylase one.

When using fully modified malts, this pause is limited, although this is possible and not entirely true.

Starch molecules break down due to the action of two enzymes beta-amylase and alpha-amylase, but they act on starch molecules in different ways.

Beta-amylase acts on the ends of starch molecules, resulting in maltose. Therefore, this pause is often called maltose. Beta-amylase is characterized by a temperature range of 63-70 gr.

Alpha-amylase works at higher temperatures 67-72 gr. This enzyme acts on the starch molecule in random parts of the chain, producing complex sugars - dextrins. Alpha-amylase works together with beta-amylase, so they try to maintain the optimum temperature of 68 degrees. The fact is that alpha-amylase acting randomly on starch molecules creates sites for the action of beta-amylase.

Single and multi-step mashing

Multi-step mashing has been considered the benchmark in brewing for many years. But in recent years, things have changed, now not only homebrewers use one-step mashing, but also breweries.

Of course, single-step mashing has its advantages over multi-step mashing, first of all, a shorter process time, and for commercial breweries, it also saves money.

When should you use multi-step mashing? The answer is obvious, if you are unsure about your choice of malt, then it is better not to risk it, and even more so if you know that your malt contains a high percentage of unmalted components.

It remains to sum up. I tried not to clutter you up with various complex terminologies and not delve into biochemical processes as much as possible. If you have any questions, leave them in the comments, I will answer them as they come up. Well, in the next article, I will try to talk about what a simple set can be used for grain brewing.

Temperature range: 35 - 45 °C

The acid rest can be used following the soak in any mashing method. During the acid break, the pH of the mash drops to the values we need, glucans are also destroyed, which turn the mash into a paste. The typical temperature range is 35-45°C, where the phytase enzyme breaks down phytin molecules, releasing phytic acid, which lowers the pH of the mash.

Phytase is very sensitive to heat, so most of it is destroyed when heated during malting. For the same reason, phytase is present only in lightly roasted malts. Moreover, it really reveals itself when using soft water with a small pH buffer and lightly modified malt. Typically, to change the pH of the mash, simply add acid while adding water to one of the rests. Another reason brewers often ignore this pause is that it takes at least an hour for a noticeable change in mash pH to take place.

The second role of this temperature pause is the breakdown of glucans. Beta-glucans are carbohydrates found in grains along with starch. Beta-glucanase is an enzyme that breaks down these carbohydrates. There are a number of similar enzymes active at temperatures up to 60°C, but the most important of these, 1,4 beta-glucanase, is most active at 45°C. Most beta-glucans are in rye, wheat, oats and lightly modified malts. Beta-glucans are known to be responsible for haze in beer.

Beta-glucans should not show up in fully modified malts, however, if there are problems with filtration or cloudiness of the beer, a 15 minute acid break should be taken.

Protein pause

Temperature range: 45 - 59 °C

In this temperature range, 2 enzymes work - proteinase and peptidase, known as proteolytic, enzymes from the class of hydrolases that cleave the peptide bond between amino acids in proteins.

Proteinase works with proteins from long chains of amino acids, splitting them to medium length. Pepdidase promotes the cleavage of terminal amino acids from protein molecules. The optimal temperature for the action of these enzymes is different, so it is possible to prefer the action of one enzyme to another.
Brewers don't need proteins from the long chains of amino acids in their wort. A high concentration of such proteins leads to cloudiness and instability of the beer. At the same time, we are interested in proteins from medium chain amino acids - they add stability to the foam and body to the beer. The optimum temperature for peptidase is 45-53 °C, for proteinase - 55-58 °C. A pause of 15-30 minutes in the proteinase-optimal temperature range reduces haze and does not adversely affect beer foam or body.

Another important point is that low temperature rests are more effective in thick mashes (1.7 - 2.1 liters per kg ground malt). Further, the mash can be made more liquid by bringing its temperature with hot water to the saccharification pauses.

A weak action of beta-glucanase is also observed during the protein pause. For this reason, some brewers do this very protein break. Do not protein rest at 45-53°C to avoid problems with head retention in your beer. If you are brewing beer with lightly modified malt, then a temperature range of 55-58°C will be helpful in reducing the viscosity of the mash.
Whether or not this pause affects the breakdown of proteins, and the quality of the wort depends on it. Excessive stirring and the time spent on the pause has a positive effect on the extractivity of the mash. This is especially true for brewers who mash the mash infrequently or tend to get poor brew efficiency.

Saccharification

Temperature range: 61 - 72 °C

The only temperature pause that cannot be dispensed with is the saccharification pause. When using fully modified malt, it is often limited to it.

Starch conversion is carried out by two enzymes that attack the starch molecules in different ways. These enzymes are called diastatic. Usually pause saccharification is carried out at 61-71°C. Sometimes a narrower range of 66-70°C is used. Remember that enzyme action does not stop completely outside its temperature range.

Beta-amylase bites off the ends of starch molecules, resulting in maltose. Since starch molecules can be very long, the process can take up to two hours. A long pause at the beginning of the temperature range makes your beer drier.
Another enzyme, alpha-amylase, acts in the higher temperature range of 68-72°C, although it also works at lower temperatures. Alpha-amylase breaks starch molecules at random locations in the chain. This enzyme is rather bulky and cannot act at the branching sites of the chains, resulting in non-fermentable sugars - dextrins. These sugars give the beer body and sweetness. A short 20-minute rest in a fairly thick mash (2 liters of water per 1 kg of malt) will produce a very dense, full-bodied beer.

This is especially true for beers that are brewed with low diastatic malts, such as pale.

Alpha-amylase is usually used along with beta-amylase to produce a beer with a moderate and dense body. Here the idea is that by breaking the starch molecules, alpha-amylase gives new ends of the molecules for beta-amylase to work. Operating at 66-67°C, these enzymes produce moderately fermentable wort that is popular with homebrewers. A temperature of 68°C will produce a fuller-bodied beer, but not overly sweet or intrusive.

A typical duration of a saccharification pause is 60 minutes. Most types of malt saccharify much faster.
Alpha-amylase is less active and less stable in wort that is low in calcium ions. This is especially true for liquid mash.

Mash out

Temperature range: 76 - 78 °C

Any beer that needs to be full-bodied needs a mash-out, a five-minute rest at 76-77°C. Also, make sure that the pellet bed stays at this temperature during rinsing and filtering. The filtered wort must also not cool below this temperature, otherwise the enzymes will continue their work already in the collected wort. Mashing also reduces the viscosity of the wort and improves the filtration rate of the wort.

acid pause

Temperature range: 35 - 45 °C

Beta-glucans should not show up in fully modified malts, however, if there are problems with filtration or cloudiness of the beer, a 15 minute acid break should be taken.

Protein pause

Temperature range: 45 - 59 °C

In this temperature range, 2 enzymes work - proteinase and peptidase, known as proteolytic, enzymes from the class of hydrolases that cleave the peptide bond between amino acids in proteins.

Proteinase works with proteins from long chains of amino acids, splitting them to medium length. Pepdidase promotes the cleavage of terminal amino acids from protein molecules. The optimal temperature for the action of these enzymes is different, so it is possible to prefer the action of one enzyme to another.
Brewers don't need proteins from the long chains of amino acids in their wort. A high concentration of such proteins leads to cloudiness and instability of the beer. At the same time, we are interested in proteins from medium chain amino acids - they add stability to the foam and body to the beer. The optimum temperature for peptidase is 45-53°C, for proteinase - 55-58°C. A pause of 15-30 minutes in the proteinase-optimal temperature range reduces haze and does not adversely affect beer foam or body.

Another important point is that low-temperature rests are more effective in thick mash (1.7 - 2.1 liters per kg of ground malt). Further, the mash can be made more liquid by bringing its temperature with hot water to the saccharification pauses.

Saccharification

Temperature range: 61 - 72 °C

The only temperature pause that cannot be dispensed with is the saccharification pause. When using fully modified malt, it is often limited to it.

Starch conversion is carried out by two enzymes that attack the starch molecules in different ways. These enzymes are called diastatic. Usually, the saccharification pause is carried out at 61–71°C. Sometimes a narrower range of 66–70°C is used. Remember that enzyme action does not stop completely outside its temperature range.

Beta-amylase bites off the ends of starch molecules, resulting in maltose. Since starch molecules can be very long, the process can take up to two hours. A long pause at the beginning of the temperature range makes your beer drier.
Another enzyme, alpha-amylase, acts in the higher temperature range of 68-72°C, although it also works at lower temperatures. Alpha-amylase breaks starch molecules at random locations in the chain. This enzyme is quite bulky and cannot act at the branching sites of the chains, resulting in non-fermentable sugars - dextrins. These sugars give the beer body and sweetness. A short 20-minute rest in a fairly thick mash (2 liters of water per 1 kg of malt) will produce a very dense, full-bodied beer.

This is especially true for beers that are brewed with low diastatic malts, such as pale.

Alpha-amylase is usually used along with beta-amylase to produce a beer with a moderate and dense body. Here the idea is that by breaking the starch molecules, alpha-amylase gives new ends of the molecules for beta-amylase to work. Operating at 66-67°C, these enzymes produce a moderately fermentable wort that is popular with homebrewers. A temperature of 68°C will produce a fuller-bodied beer, but not overly sweet or intrusive.

Mash out

Temperature range: 76 - 78 °C

Any beer that needs to be full-bodied needs a mash-out, a five minute rest at 76-77°C. Also, make sure that the pellet bed stays at this temperature during rinsing and filtering. The filtered wort must also not cool below this temperature, otherwise the enzymes will continue their work already in the collected wort. Mashing also reduces the viscosity of the wort and improves the filtration rate of the wort.

And it makes no sense to fake it. The production process itself seems very simple, almost “just add water”, and the rest of the nature will handle itself.

- Can't be! – you will say, but partly it is. Brewers, in fact, simply create favorable conditions for the flow of all natural processes: grain dissolution, disinfection, further maturation.

So, for the dissolution of grain substances, it is necessary to maintain a certain temperature of water, and over time it must change with pauses.

Mixing ground grain with water of the required temperature to dissolve the extract is called mashing. So, what are the temperature rests for beer mashing?

In any grain there is a set of enzymes that are activated at a specific temperature for each. Why is it so difficult? The answer is simple, sugars are “encoded” in the form of a long starch molecule. This molecule is “hidden” in the granules, and the granules are in protein shells that are under the aleurone layer of the grain. All this is “stored” under layers of films and outer shells of grain, protecting it from external influences.

Water in this case acts as an energy carrier, it penetrates through the membranes, activating the enzymes of the aleurone layer, which “clear” the path of the liquid to the protein membranes. At this stage, water-activated enzymes are “connected”, which provide protein breakdown and open the way to starch granules. From exposure to water, starch granules swell and burst, providing access to the "holy of holies" - starch. Water, as a source of life, awakens the grain from hibernation, stage by stage, it starts the physico-chemical processes in the grain in order to achieve the complete and unconditional splitting of the starch molecule into sugars. Important here are the temperature pauses during mashing for beer.

Does the grain destroy itself under the influence of water?
- Yes.
- For what?
To break down starch into sugars.
- Why?
“Because sugars are a source of nutrition for the future sprout, and the brewer, in turn, uses them for his own needs. Therefore, the grain contains enzymes, like the locks of closed doors, and the key is the temperature and the duration of the temperature pauses.

Such a long introduction will make it possible to understand the causes of the processes occurring during mashing and the immediate meaning of the phased temperature pauses.

Now let's talk about how you can adjust the composition of sugars in the wort and the taste of the finished beer with temperature pauses.

First step is the splitting of polysaccharides of grain films and its protein structures. The optimum temperature for these processes starts from 35-37 C° . Water of this temperature penetrates into the structures of the shells and activates the cytolytic enzymes of the grain, triggering the splitting mechanism.

Why 35-37 C°? Such is the specificity of their action. The films contain starch, but of a different structure. Enzymes break it down into polysaccharides, which are not always desirable in beer as they increase the drink's astringency, color and viscosity.

At present, this pause is practically not used, since grain films become quite permeable even at the malting stage. This happened due to the modernization of malting technology and the use of new agronomic practices in the cultivation of barley.

At this temperature, lipoxygenase enzymes are also active. These are fat soluble enzymes. They release the fat that is in the germ. He uses it as fuel for his growth. During the brewing process, fat is harmful, because it oxidizes and gives undesirable flavors to beer.

This pause can only be found in classic Czech beer recipes. with decoctions, but we'll talk about this later.

Further we heat the mash to a temperature of 45-55 C °. At this point, the proteolytic enzymes of the grain are activated. They break down its protein structures. Cell walls, connective tissue are composed of protein molecules, and inside the grain there is a protein that is completely subject to dissolution.

The proteolytic enzymes of the grain are specific, each acting on a protein structure strictly defined for it. The result of this "activity" are peptides, polypeptides, as well as soluble protein and free nitrogen. The polypeptides in beer are the building blocks for foam, while free nitrogen and soluble protein are nutrition for growth and development. Also, the presence of dissolved protein can positively affect the fullness of taste.

So, the water has already “reached” the starch, we heat it to 62-65 C °. This temperature pause during mashing is very important for beer and is the longest. At these temperatures, a complex of enzymes associated with additional protein digestion acts. The main role in this pause is assigned to the action of beta-amylase. As mentioned earlier, the starch molecule is a long chain of branched molecules. Beta-amylase destroys it, leaving large molecules of maltodextrins amylose and amylopectin, which no longer give the staining with iodine characteristic of starch. These molecules are already sugars, but too large and inedible for. The maximum activity of the enzyme at this temperature is approximately 30 minutes, but if you increase its duration, the reaction rate will slow down, but will not stop.

Beta-amylase sets the stage for alpha-amylase . In this case, we heat the mash to 71-73 C°, activating it. Alpha-amylase acts on starch molecules at the edges, splitting off small pieces of mono-, di-, trisaccharides. Of greatest importance is the resulting disaccharide maltose.

Maltose is the main source of nutrition for, the more it is, the stronger and richer the beer will be. The amount of maltose depends on the initial amount of maltodextrins that the alpha-amylase acts on, as well as the duration of the reactions, that is, the longer the amylases are allowed to act on the starch, the more sugars we get, and the more extract the brewer will get.

Summing up, we see that brewers do three basic temperature rests when mashing for beer. This:

protein 45-55 C°;
maltose 62-65 C°;
and saccharification 72-77 C°.

The maximum temperature pause during mashing for beer is 78 C°. At this temperature, the action of enzymes ceases due to their destruction. Therefore, if the brewer wants to extend the digestion processes, he should not exceed this level.

However, the highest quality is not always at hand, in turn, low-quality grains contain few active enzymes, therefore, even after standing for a considerable time at all the required temperatures, the mash will be undersaccharified. In this case, enzyme preparations can be used.

These are the same enzymes, but obtained as a result of the vital activity of microorganisms of a fungal nature. In this way, all types of enzymes are synthesized, which break down starch at different stages. What can I say, human saliva contains a complex of amylases that break down starch.

Such enzyme preparations are often thermostable; when using them, there is no need for strict adherence to temperature pauses and their duration. They help to break down even the starch of unmalted grains, helping the brewer achieve his desired extract yield.

What's the matter? Why does one beer have a dry aftertaste while another has a sweet aftertaste? The secret lies in the duration of exposure to enzymes at selected temperatures.

The ideal congestion is the one where everything is split. It is unlikely that we would drink such beer, because it would not have foam, it would have a dark color, like old beer, it would be very strong, dry, sour. It is for this reason that the protein pause is so short - up to 20 minutes, because it is necessary that the peptides for the foam remain. In some cases, it is skipped altogether.

The maltose pause is from 30 to 60 minutes so that there is not too much dextrins, and the saccharification pause is reduced to 20 minutes so that all the dextrins do not have time to break down to maltose.

It all depends on the preferences of the brewer, the quality of the raw materials used, the chosen style of drink. If the raw materials are of very high quality, then with short temperature pauses a large amount of starch can break down. In this case, it is recommended to reduce the duration of pauses or, in general, to exclude some of them.

If the brewer uses unmalted grain, he will increase the maltose rest to the limit in order for the saccharification to succeed. Well, if you need to brew beer for diabetics, then you should provide a higher content of difficult-to-ferment dextrins, after reading this article you already have an idea of \u200b\u200bwhat to do in this situation.

The choice of temperature rests for beer mashing is the basis of the fundamentals for creating the best beer. If you have any questions, be sure to ask them in

Introduction

Step mashing is the process of increasing the temperature of the mash in order to pass through the temperature breaks. The ubiquity of the use of highly modified malts has eliminated the need for temperature step mashing in most cases. So why do we need to know more about the process and science of step mashing? Everything is simple. By knowing exactly what you are doing, the mashing process will be better controlled, and the result when brewing a specialty beer will be better.

Incremental mashing allows brewers fine-grained control over the preparation of the wort, resulting in dry or sweet beer, velvety or empty taste. It can be seen that the efficiency of brewing increases with the use of additional pauses. Understanding the chemistry and biochemistry of the process helps grain brewers create their own temperature break schedule.

Malt modification

Malting plays a key role in brewing. The purpose of mashing is just to continue the malting process, everything that happens in the malthouse should influence your choice of mashing method.

The main purpose of malting is to start the germination of barley, later drying, to stop germination. For brewers, this is a very important process, during which the main enzymes are formed, in addition, it triggers 2 important changes in the grain. First, glucans in cell membranes are broken down, and proteins are also broken down, which saturates the wort with amino acids necessary for yeast growth, reducing the likelihood of protein turbidity in beer, increasing its biological stability. The degree of cleavage of glucans and proteins is called modification. Most malts these days are fully modified. Glucans and proteins are broken down to such an extent that brewers just need to start the process of converting starch into sugars, and a quality wort is ready. Lightly modified malt allows the brewer more control over the wort preparation process.

Grain modification softens the endosperm, while unmalted barley is very hard. Many producers have lightly modified malt in their range, which is reflected in the name, for example, "Less Modified Pilsner Malt" from Briess. When dealing with such malts, the decoction or stepwise mashing method should be used. The same can be said about malt of unknown quality.

Table 1

Enzymes

Enzymes are proteins that catalyze chemical reactions. There are also RNA-based enzymes, but they do not play the first role in mashing.

Proteins are long, unbranched chains of amino acids ranging from 50 to 8000 units. Some sections of the protein can be formed by amino acids in the form of a spiral, while others in the form of a sheet. The whole sequence of spirals and sheets forms 3-dimensional figures. The shape of proteins is largely maintained by van der Waals forces, which are very weak and break with changes in temperature or pH.

The shape of enzymes determines their function. Enzymes are specific to substrates. So the anchor site of a particular enzyme will fit only to its substrate center. In our case, the amylase enzyme attaches to a specific element of the starch molecule and speeds up the splitting reaction into 2 sugar molecules.

With stepwise mashing, enzymes that break down starch and proteins work on the principle of hydrolysis, which literally translates as “breaking down with water”. So the amylase enzyme is connected to two future sugar molecules. As soon as the water molecule enters the zone of close proximity to the bond between the molecules of future sugars, the enzyme accelerates the reaction between the hydrogen (H+) of the water molecule and the base (OH-) of the sugar. In fact, the bond between the sugar molecules is replaced by a water molecule, which splits, breaking the starch molecule. As soon as the bond is broken, the enzyme is released, since the substrate center of the desired type ceases to exist. Further, the enzyme again enters another substrate center and continues its action.

If any of the bonds stabilizing the form of the enzyme is destroyed, it cannot hook up to the substrate center, since its anchoring site changes. When the structure of the enzyme changes under the influence of temperature, its denaturation occurs. After denaturation, most of the enzymes involved in mashing cannot return to their previous state. Those. denaturation completely deactivates the enzyme.

In the brewing literature, you can find the optimal temperature range for various enzymes. (See Table 2 for reference.) For advanced brewers, it is important to understand the implications of these data. Enzymes are simple "mechanisms" that act separately from each other, and their action depends on their shape. In a mash, when an enzyme collides with a starch or complex sugar substrate center, a chemical reaction breaks down molecules. When the mash is heated, the rate of the reaction with the catalyst increases, since the protein (enzyme) molecules begin to move faster and have time to collide with a large number of substrate centers per unit time. In a mash, all enzymes are active from freezing to denaturing. The literature usually gives the optimal temperature for the operation of enzymes, however, this does not mean that the enzyme is inactive at a different temperature. It's just that this work is going more slowly. The top point of enzyme activity is determined by the denaturation temperature. Heating the mash above the denaturation temperature does not mean that the enzymes will stop working immediately. For example, beta-amylase is denatured in 40-60 minutes at a temperature of 65 degrees. Alpha-amylase will work for another 2 hours when the temperature rises to 67 degrees. Keep in mind that by raising the temperature of the mash, you are not instantly turning the enzymes on and off, this whole system is very inert.

table 2

So, there are 4 factors that determine the speed of fermentation - enzyme concentration, density, temperature and pH of the mash. The brewer himself can manipulate all 4 factors when performing a step mash.

acid pause

Beta-glucans should not show up in fully modified malts, however, if there are problems with filtration or cloudiness of the beer, a 15 minute acid break should be taken.

Protein pause

Traditionally, the temperature range of 44-59°C is called the protein rest. Nowadays, many brewing scientists do not believe that protein breakdown should occur during mashing, leaving this process to the maltists. However, we should consider the action of enzymes in this temperature pause.

In this temperature range, 2 enzymes work - proteinase and peptidase, known as proteolytic, enzymes from the class of hydrolases that cleave the peptide bond between amino acids in proteins.

Brewers don't need proteins from the long chains of amino acids in their wort. A high concentration of such proteins leads to cloudiness and instability of the beer. At the same time, we are interested in proteins from medium chain amino acids - they add stability to the foam and body to the beer. The optimum temperature for peptidase is 45-53 °C, for proteinase - 55-58 °C. A pause of 15-30 minutes in the proteinase-optimal temperature range reduces haze and does not adversely affect beer foam or body.

Whether or not this pause affects the breakdown of proteins, and the quality of the wort depends on it. Excessive stirring and the time spent on the pause has a positive effect on the extractivity of the mash. This is especially true for brewers who mash the mash infrequently or tend to get poor brew efficiency.

Saccharification

The only temperature pause that cannot be dispensed with is the saccharification pause. When using fully modified malt, it is often limited to it.

Starch conversion is carried out by 2 enzymes that attack the starch molecules in a different manner. These enzymes are called diastatic. Usually, the saccharification pause is carried out at 61–71°C. Sometimes a narrower range of 66–70°C is used. Remember that enzyme action does not stop completely outside its temperature range.
Beta-amylase bites off the ends of starch molecules, yielding maltose. Since starch molecules can be very long, the process can take up to 2 hours. A long pause at the beginning of the temperature range makes your beer drier.

Another enzyme, alpha-amylase, acts in the higher temperature range of 68-72°C, although it also works at lower temperatures. Alpha-amylase breaks starch molecules at random locations in the chain. This enzyme is quite bulky and cannot act at the branching sites of the chains, resulting in non-fermentable sugars - dextrins. These sugars give the beer body and sweetness. A short 20-minute rest in a fairly thick mash (2 liters of water per 1 kg of malt) will produce a very dense, full-bodied beer.

This is especially true for beers that are brewed with low diastatic malts, such as pale.

Alpha-amylase is usually used along with beta-amylase to produce a beer with a moderate and dense body. Here the idea is that by breaking the starch molecules, alpha-amylase gives new ends of the molecules for beta-amylase to work. Operating at 66-67°C, these enzymes produce a moderately fermentable wort that is popular with homebrewers. A temperature of 68°C will produce a fuller-bodied beer, but not overly sweet or intrusive.

A typical duration of a saccharification pause is 60 minutes. Most types of malt saccharify much faster.

Alpha-amylase is less active and less stable in wort that is low in calcium ions. This is especially true for liquid mash.

Mashing also reduces the viscosity of the wort and improves the filtration rate of the wort.

How to prepare beer wort. All about Temperature Pauses in Brewing: Acid and Protein Pause and Enzymes

Grain malting

Enzymes