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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)
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?