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The saccharification interval is one of the most important stages during the mashing of malts. During the saccharification interval the unfermentable starch in the malt is transformed into sugars for the yeast to ferment. However, this description is very superficial because behind this process, there are a number of enzymes that make the final product, beer, taste so unique.


Mashing is, one could say, a continuation of the malting process. It consists in steeping the malt in hot water at specific temperatures. For the saccharification interval, this should be between 62°C and 72°C.


Diastatic and proteological enzymes


Two types of enzymes are active during the saccharification interval.

Diastatic enzymes, which break down starch into single glucose molecules:

  • Amylase: alpha-amylase (60°C - 75°C), beta-amylase (55°C - 65°C)

  1. Borderline dextrinase (60°C - 67°C)

Proteolytic enzymes, allow diastatic enzymes to work:

  • Protease/Protease [Endopeptidase (20°C - 65°C)]

    peptidase [Exopeptidase (20°C - 67°C)].

In parentheses, the temperature range at which each enzyme operates.

Each enzyme is affected by different temperatures and the pH of the mash. The optimal pH value for the enzymes to work is 5.5 - 5.8 pH. Outside this range their effectiveness will decrease. The saccharification processes are controlled by changing the temperature. This means that you can adjust it to the work of the individual enzymes and consequently adjust the wort to the malt profile you desire.

Of course there are many more enzymes involved in a full mash, but they usually work at different temperatures or their work is so marginal that there is no need to include them.




The starch reserves in the grain are packed in a protein-carbohydrate matrix (one of the protective layers in malt). This blocks the diastatic enzymes from accessing this starch, so they have nothing to work with. This is why, at the beginning of the saccharification interval, glutination takes place due to both temperature and the proteic enzymes. The malt in the pot soaks up water, and the starch in it begins to open up and liquefy. The broth takes on a sticky consistency. Only on this sticky consistency can the diastatic enzymes work. An exception is alpha-amylase, which will be discussed later.

The most optimal temperature for glutination is 65°C, but the process starts at 60°C. This is a necessary step in the saccharification interval, which fortunately (in most cases) we cannot avoid, so it does not require additional work.

Theoretically, the most optimal saccharification interval temperature is between 65°C and 67°C. This temperature is a compromise between glutination and denaturation of beta-amylase. Denaturation means that the enzyme is altered and does not function as it should.

A lower water temperature would not allow enough water to soak in for glutination to be successful. Higher temperatures are also usually not recommended because temperatures above 67°C rapidly accelerate the denaturation of the aforementioned beta-amylase. It must be noted that the denaturation of this enzyme continues all the time, even at the lowest threshold of the accepted fork. However, for this enzyme, the maximum temperature is theoretically 65 °C and after 30 minutes of mashing malt at this temperature, about 75% of the beta-amylase is denatured and after one hour 90%. But still - at higher temperatures they denature faster, but they also work faster.

Interestingly, we can witness glutinization during everyday cooking when we use flour to thicken a sauce.


Structure of starch


It is worth reminding ourselves what starch is actually composed of. It is made up of many glucose molecules linked together by chemical bonds. This structure may resemble a chain, which is referred to as amylose. Amylose can occur individually, but it can also be linked together in more complex structures. Many amylose molecules linked together are amylopectin. Amylose molecules can also be branched, but not as elaborate as amylopectin.


Dextrins, are all the unfermented sugars, or sugars that will stay in our beer and give it sweetness. They are amylose bonds that are made up of at least four glucose molecules, but also amylopectin.




The last term we need to know is hydrolysis. This is the reaction that takes place between water and the substance dissolved in it. During mashing, hydrolysis refers to the breaking of starch bonds into smaller molecules. This happens through diastatic enzymes.


What happens during the saccharification break?


The saccharification interval is carried out at temperatures of 62°C - 72°C. It is in this range that the diastatic enzymes described earlier come into action, once the starch has liquefied (glued together).

It should be noted that some of the enzymes are created only during malting, in the aleurone layer of the grain (the outer layer of endosperm cells in the grain), and some already existed in the grain before. Those that do exist are beta-amylase and half border dextrinase. As for the rest of the border dextrinase, it is formed during malting. So does alpha-amylase.

The action of alpha-amylase and beta-amylase is to hydrolyze the bonds between the individual glucose molecules combined in amylose and amylopectin.

However, their work is slightly different - beta-amylase only cuts the ends of the branches and forms what is called maltose - which in turn is made up of two glucose molecules. In other words - beta-amylase is not able to hydrolyze other bonds than two glucose molecules joined together. In addition, it cannot act, for example, in the middle of the amylose chain - the limits of its action extend closest to three glucose molecules from the connection of individual branches (this place is called the border dextrin of beta-amylase).

As for the apha-amylase - it has the ability to break down maltose into single glucose molecules. What's more - it can break the bonds almost anywhere in amylose and amylopectin, making it easier for beta-amylase, which, having more smaller pieces, also has more branch ends to work on.

The alpha-amylase can get within one glucose molecule of the amylopectin branch (the dextrin limit of alpha-amylase).

It can be said that mashing at 62°C - 65°C favors beta-amylase. Higher, 68°C - 72°C, favors alpha-amylase.

Where alpha-amylase fails, border dextrinase comes in. This cuts the remaining chains into smaller ones on which alpha-amylase and beta-amylase can start working again.

After the recommended 60 minutes of this work, all the starch in the malt grain is saccharified, but this is best checked with an iodine starch indicator.


What about saccharification interval at higher temperatures?


As you may have noticed before - the vast majority of enzymes stop working at temperatures above 67°C. The exception is alpha-amylase, and it is because of this enzyme that the mashing fork is so high. Alpha-amylase can work on unconjugated starch, but then its efficiency decreases, so the finished beer will contain more dextrins.

When mashing at 68 °C - 72 °C, the starch is also hydrolyzed because the alpha-amylase can still work. However, the reagent of the hydrolyzed bonds is much smaller, and thus our yeast has less nourishment. Even so, the starch is broken down into smaller glucose chains - non-refermentable - so such beer is sweeter.

For example, maltose (consisting of two glucose molecules) is easily fermented by yeast. Maltose (three glucose molecules), on the other hand, is fermented by only high-fermenting yeast, but only after the yeast has used up all the glucose and maltose.

Interestingly - there is a known relationship between mashing at different temperatures - lower gives more fermentable sugars, so the beer will be more dry, but with more alcohol. Beers that have been saccharified at a higher temperature will be sweeter, more substantial, but with less percentage.

To summarize:


During a saccharification break, several enzymes are at work. Some of them, with the help of the temperature, have to bring about glutination, after which the diastatic enzymes, which hydrolyze the starch, can go to work.

Any temperature between 62°C and 72°C can give us different results - beer saccharified in the lower limits will be dry and high alcohol, while that from the high temperatures will be sweet and less alcoholic.