Abstract: In beer production, the turbidity of the fermentation broth is theoretically proportional to the concentration of beer: the higher the concentration, the higher the turbidity, which is related to the internal soluble substances in the beer. But in the end, there should be a turbidity standard for the finished sake of the same concentration. This article combines some of its own practices to comprehensively analyze the impact of several key control points such as raw materials, saccharification, yeast, fermentation, and filtration on the turbidity of the finished beer and the solutions.

1. Poor malt quality

The main reason is that malt has low solubility, high viscosity, low brittleness, high content of β-glucan, and many medium and high molecular soluble substances. These high molecular substances are still suspended in the wort after filtration or even boiling. , Resulting in an increase in wort turbidity.

Solution:

(1)A compound enzyme preparation containing protease, glucanase and amylase is used to decompose the para-polymer substances in the wort.

(2)Use some protein, polyphenol material precipitation agent or clarifying agent. Such as tannin, carrageenan, etc., to remove the "turbid substances" in the wort.

(3)Appropriately increase the proportion of auxiliary materials to "dilute" the polymer substances.

(4)Strengthen the iodine test inspection of the saccharification process to complete the iodine test reaction during the saccharification process.

(5)Generally, poor quality malt should not be used alone. Adding some good malt can not only prevent some undesirable phenomena, but also mutually use advantages to achieve a multiplier effect.

Shandong Zunhuang Brewing Equipment Co., Ltd. specializes in the production of craft beer equipment, private order, quality assurance! Telephone consultation0531-87066989

2.Grinding degree and use ratio of malt

The crushing process of the raw materials is not well controlled. Too coarse or too fine will affect the turbidity of the wort. If the raw material is too coarse, it will not only affect the precipitation of the extract, but also cause the filter grain layer to be too loose, causing a large number of macromolecular components to dissolve; if the raw material is too fine, it will cause some substances in the malt skin to precipitate and cause filtration difficulties. Generally speaking, the lower the proportion of good malt is, the turbidity of the wort is on the rise; as the proportion of auxiliary materials increases, the proportion of macromolecular substances in the wort can indeed be reduced, but if the proportion of auxiliary materials is too high, the wort is difficult to decompose The increase in the low-molecular-weight dextrin component of the wort will also promote the turbidity of the wort.

Solution:

(1)Control the degree of pulverization of raw materials and determine the best pulverizing roller distance.

(2)Reasonably mix the ratio of poor quality malt and auxiliary materials in the raw materials.

3.Wort filtration factors

Wort filtration is a very important process in the beer production process. Its purpose is to separate the dissolved substances from the raw materials in the saccharification formulation from the insoluble lees in the shortest time after the saccharification process, so as to obtain clarified wheat Juice, and obtain a good yield of extract. The quality of the filtering effect of the wort directly affects the later fermentation of the wort, the filtering of sake, the foam and flavor of the beer, and ultimately the turbidity of the beer. Therefore, controlling the turbidity of "semi-finished products" is also of great significance to controlling the turbidity of "finished products".

In the filtration process, the control of the water temperature of the spent grains is very important. As the temperature of the spent grains rises, the turbidity of the wort tends to decrease; but if the water temperature is too high, the turbidity will rebound again. This is because the water temperature is too high, resulting in the mash. Re-gelatinization of starch residues in the liquid will also cause excessive washing of the spent grains. At the same time, maintain a stable filtration speed and suitable tillage depth to ensure the formation of the filter grain layer and the smooth flow of the wort, and improve the brightness of the wort. However, if the cultivator is frequently turned on during the operation, or the cultivator is too deep, it will destroy the formed layer and cause the turbidity of the wort.

Solution:

(1)Control the appropriate temperature of the lees water.

(2)Maintain a stable filtration flow rate and a suitable depth of the tiller, and maintain the filter layer.

Shandong Zunhuang Brewing Equipment Co., Ltd. specializes in the production of craft beer equipment, private order, quality assurance! Telephone consultation0531-87066989

4.Wort boiling strength is not enough

The boiling intensity of the wort in the boiling pot will directly determine the clarity of the wort, because the wort undergoes violent physical and chemical reactions during the boiling process. In the meantime, the concentration process of wort is also the process of wort clarification, including the removal of thermal coagulum and the elimination of undesirable volatile substances. Therefore, controlling the boiling intensity plays an important role in ensuring the quality of wort and preventing wort oxidation.

Excessive boiling intensity will accelerate the color reaction of the wort, and at the same time will destroy the wort's longing distinction and affect the foam performance of beer. The longer the boiling time, the greater the amount of coagulated protein, but if it is too long, some coagulated proteins and their complexes will be reconstituted and the wort will become more muddy; if the boiling strength is not enough, or the pH of the wort is improperly controlled , The boiling steam pressure is unstable, etc., which will cause insufficient precipitation of the coagulable nitrogen of the wort, thereby affecting the turbidity of the wort.

solution:

(1)Determine the reasonable boiling time and intensity.

(2)Ensure the stability of the supply steam pressure as much as possible during production.

(3)The hops used in the boiling process should be kept fresh as much as possible, because the use of too old hops will be subject to oxidation, and the ability of the tannins to precipitate proteins will decrease, resulting in more macromolecular protein residues in the wort.