Beer brewing water（3） - treatment method of beer brewing water

Beer brewing water - treatment method of beer brewing water

1. Boiling method 

Principle: Make the bicarbonate or magnesium dissolved in the water form insoluble calcium carbonate or magnesium precipitate to reduce most of the temporary hardness in the water.

Method: Atmospheric pressure boiling method, in any container, heat water for tens of minutes, and keep stirring, remove CO2, form calcium carbonate to settle naturally, accumulate at the bottom, use decantation method to separate the treated water. If the water to be treated contains a lot of magnesium bicarbonate, because the formed precipitate precipitates slowly, and its solubility increases with the decrease of temperature, it must be filtered immediately after boiling or filtered together with a coagulant.

Advantages: The method is simple, does not require special equipment, and is suitable for small factories.

Disadvantages: long time, high heat consumption and high cost; the temperature of the treated water is high, and it must be cooled before it can be used for saccharification; the effect on water with high magnesium bicarbonate content is not good.

2. Liming method 

Principle: Reduce the temporary hardness and other harmful components of water.

Method: Pour the water to be softened into a large water tank (cylindrical cone-bottom container), add the pre-digested milk of lime solution, and at the same time fully stir with compressed air for 10-20 minutes, let it settle for 4-5 hours, and draw it out from the upper part of the container for treatment After the water, the sediment is discharged at the bottom of the cone.

Advantages: After lime treatment, most of the temporary hardness is removed, and it has a reducing effect on organic matter, silicate and iron ions.

Disadvantages: ①The remaining Ca(OH)2 is not allowed in the water, otherwise it will seriously affect the saccharification; ②When the raw water contains less calcium carbonate, a large precipitate cannot be formed after adding lime, so it is difficult to remove the precipitate, and a coagulant needs to be added; ③ Larger volume storage tanks are required.

3. Plaster method 

Principle: counteract the acid-reducing effect of bicarbonate.

Method: Put the gypsum directly into the saccharification feeding water according to the calculated dosage.

Dosage: Add 50~200g gypsum per ton of feed water.

Advantages: simple method, commonly used

Disadvantages: After the above chemical reaction, calcium phosphate precipitation will occur after adding gypsum, that is, part of the soluble phosphate will be lost; water with high hardness of calcium sulfate should add less or no gypsum, otherwise more harm than benefit.

4. Acid addition method 

Principle: Eliminate the alkalinity formed by bicarbonate in water by adding acid. Adding acid does not change the total hardness of the water, but it can change the carbonate hardness to non-carbonate hardness, so as to reduce the RA value and pH value of the water and improve the water quality. If the total hardness and temporary hardness of the water are high, the water should be treated by other methods first, and then add acid to reduce the RA value.

Method: Do a small test first, and adjust the pH value to 5.2-5.6. The places where acid is added are mostly saccharification pots and boiling pots. Adding to the boiling pot can significantly reduce the pH value of the mash, and its ability is twice that of adding to the mash tun.

Type: The type of acid added varies from factory to factory. Generally, lactic acid is added more, and hydrochloric acid, phosphoric acid, and sulfuric acid are also added. Adding various acids also has different effects on beer flavor. Lactic acid is added to make beer mellow, and when it is too much, it will be bitter; adding hydrochloric acid can make the taste of beer full and rich; adding phosphoric acid is generally to increase the nutrition of yeast.

Effect: Enzyme action is strengthened, saccharification is quick; beer is light in color and soft in taste; protein coagulation and precipitation are good, and wort clarification is good.

5. Other improvements 

In addition to the above water treatment methods commonly used in production, there are ion exchange, reverse osmosis and electrodialysis.

① Ion exchange method: use an ion exchanger to treat water, and you can selectively remove some components in the water. Its advantages: the method is reliable, and the water quality after treatment is good. According to different designs, it can meet different process requirements; the water output is large, and the cost of water treatment is moderate. Disadvantages: complex management, intermittent water discharge from the multiple bed system, frequent regeneration, long regeneration cycle; large amount of acid and alkali for regeneration.

② Reverse osmosis method: Under external high pressure, make it overcome the osmotic pressure of the aqueous solution itself, so that water molecules pass through the semi-permeable membrane, while salts cannot pass through the semi-permeable membrane, thereby removing various salts in the water.

③Electrodialysis method: Under the action of an external DC electric field, the selective permeability of anion and cation exchange membranes to ions in water is used to transfer some ions to another part of water to achieve the purpose of desalination.