Sugar Production Method: Multi-step Leaching And Saccharification

Typical brewing equipment

Two-in-one mash tun and boiling tun (all-in-one) with integrated filtration and optional tillage and temperature control.

Description

Compared with the single-step infusion mashing method, this method can adjust the sugar content in the wort by controlling the temperature.

Due to the rapid inactivation of β-amylase during the common single-temperature mashing process (66-68°C), the final fermentation degree is limited, and even extending the mashing rest time cannot overcome the problem of enzyme inactivation.

For beer varieties such as Pilsner and Bock that require a higher degree of fermentation, we can extend the rest time to 60-62°C. Because at this temperature, the inactivation rate of β-amylase is very slow.

The choice of saccharification rest time and saccharification method depends on the enzyme content in the malt and the degree of malt crushing. When the malt is crushed, the decomposition of starch can be completed within 20 minutes; when the malt is crushed, even if the saccharification time is extended to 60-90 minutes, the decomposition of starch may not be completely completed.

It is difficult to identify the crushing state of home-brewed beer. Home-brewed beer enthusiasts need to make appropriate judgments based on their own circumstances. After many experiments, it was found that using the same yeast strain, different crushing states, the final fermentation degree of wort is different.

When the mashing stops at 70-72°C, the time should be extended until the iodine test passes (usually no more than 20 minutes). Of course, in order to obtain a higher mashing rate, the mashing time at this temperature can be extended to 45 minutes, which can also improve the taste and make the beer thicker because more glycoproteins are produced.

Iodine test: A method for detecting starch decomposition. Add 0.02mol/L iodine solution to the cooled mash. At room temperature, the iodine solution will change from purple to red when it encounters starch and larger molecular dextrins. However, sugars and small molecular dextrins are not suitable for electro-hydraulic color change. If the iodine test does not change color, the "iodine test is normal".

Typical mash rest temperature range

• Maltose rest 60-64°C: 20-60 mins

• Optional intermediate rest 67°C: 15 mins. (more fermentation)

• Mash rest at 70 to 72°C until iodine test is passed

• Then temperature is raised to 78°C to start the washing process

• Also: optional protein rest at 45-55°C

The resting time of protein is about 5 to 15 minutes. During the resting period of protein, the protease in malt breaks down the macromolecular protein into macromolecular protein decomposition products, which is conducive to the retention of foam, foaming and the mellowness of the beer. Another peptidase in malt will produce more low molecular weight protein decomposition products (free amino acids), which are essential nutrients for yeast reproduction during fermentation.

The optimal working temperature range and pH value of the two proteases overlap, generally: pH = 4.2-5.3; 45-55℃. The protein resting at 49-54℃ can reduce the protein that causes the turbidity of cold beer and improve the beer foam.

Wheat malt and dark base malt are more likely to lack free amino acids than light malt. Lack of free amino acids will lead to slow yeast fermentation, low fermentation degree, and produce a large amount of byproduct hydrogen sulfide.

But not all yeasts need a lot of free amino acids. Most ale yeasts do not need too much free amino acids, while some low-fermentation yeasts and wheat beer yeasts need a lot of free amino acids. Therefore, it is necessary to pay attention to the length of protein resting time, which is the process of protein small molecule, which is also crucial to the stability of foam and the mellowness of the body.

Not all malt used for home brewing needs to be rested, but it is often necessary when:

• Using more than 25% unmalted malt

• Using a boil-dry mash

• Brewing traditional beers, such as traditional American lagers or Munich stouts

• Using incomplete malt

Types of beer that multi-step brewing is suitable for

Light lagers, especially light pilsners, have moved from boiling to infusion in many places.

Pilsners brewed using single-step brewing are often described as soft, lacking in character, and not refreshing enough, which is the opposite of what people expect from pilsners today. Compared to single-step brewing, multi-step brewing is suitable for almost all types of beer brewing.