What is sparging? What are the specific requirements?

// What is lauter sparging? What are the specific requirements? //

After the first wort (original wort) is filtered, a certain amount of extract remains in the wort layer. In order to ensure the utilization rate of raw materials, this part of the extract needs to be recovered, and these soluble components can be washed out with hot water. The process is called scouring.

The number of wort washing and operating conditions are affected by the first wort concentration, the thickness of the wort layer, the wort filterability and the boiling intensity.

 Reference method 

The concentration of the first wort: around 18-22°P, a small amount can be used several times, the wort water should just cover the wort layer, and the number of times of washing the wort can be 4 or more; the concentration is around 15-17°P, the number of times can If it is less, the amount of water used to wash the waste can be slightly more, usually about 3 times.

The thickness of the grains layer: when it exceeds 45cm, it should be used in small amounts and several times. If there is residual sugar recovery, the number of times can be more than 4 times; if it is between 35 and 40cm, the number of times is less, and the amount of water can be slightly more. Generally, it is enough to wash 3 times.

Boiler evaporation intensity: when it is higher than 7%, it can be used in small quantities and several times, depending on the residual sugar when boiling; when it is below 5%, it can be used in small quantities and several times, depending on the concentration of wort and the boiling time.

//Precautions for washing grains(sparging) //

When washing grains, in order to ensure the full recovery of the extract and the quality of the wort, the following issues should also be paid attention to:

(1) The temperature of the washing water must be suitable. Generally controlled at 76 ~ 78 ℃, preferably not more than 80 ℃, not lower than 74 ℃. If the water temperature is too high, it is easy to wash out a large amount of viscous substances and destroy a-amylase. If the water temperature is too low, the residual sugar will not be washed cleanly.

(2) The pH value of the waste water must be suitable. Generally, the pH value of the washed waste water is below 6, but the adjustment of the pH value in actual production is more troublesome. Therefore, it is required to control the pH value of the wort water as much as possible to be below 6.5, which can reduce the dissolution of husk polyphenols, and facilitate the coagulation of proteins during the boiling process of wort, and the color of the wort is also lighter.

(3) The number of times of washing the bad should also be moderate. Although the multiple recovery of residual sugar can improve the utilization rate of raw materials, the excessive washing times will wash out a lot of harmful components in the wheat husk, such as polyphenols and pigment substances, which will be detrimental to the taste and shelf life of beer. In addition, excessive washing of the wort will reduce the concentration of the mixed wort in the boiling pot, and a large amount of heat energy will be used to evaporate the water, and this energy consumption will increase the production cost.

(4) The principle of small amount and many times should be followed for washing bad. A small amount means that the washing water has just covered the bad layer, and it can be slightly higher than 2-3cm.

(5) The time to wash the bad for the first time should be mastered. A more suitable time to wash the dregs can wash away more leaching substances.

(6) It is not necessary to plough the dregs every time, especially in the case that the dregs layer is relatively loose, generally the 1st dregs washing (including the 2nd time at most) should be ploughed in principle, because at this time the dregs layer should be ploughed. The residual sugar concentration is high, and the bottom layer is compact, and the tillage grains can help to wash out the extract and loose the bottom layer.

(7) In the case of difficult filtration, the top water method is often used to reorganize the wort layer, but when the top water is used, the concentration of the wort layer and the unfiltered wort will be diluted to a certain extent, and the top water will bring a large amount of water to boiling. In this way, the number of times and the amount of water that can be washed will be affected, and the residual sugar will be too high.

Sparging is the rinsing of the mash grain bed to extract as much of the sugars from the grain as possible without extracting puckering tannins from the process.

(8) In the case that the evaporation intensity of the boiling pot is low, the method of boiling while washing the waste can be considered, which can wash out some residual extracts, but pay attention to ensure the normal boiling time.