＂higher alcohols＂ in the beer
- Jan 19, 2020
- 87
- tiantai
"higher alcohols" in the beer
The term "higher alcohols" refers to a general term for alcohols of three or more carbon atoms, and is commonly known as fusel oil in the alcohol and liquor industries. Higher alcohol is one of the main by-products in the beer fermentation process and is an important substance that constitutes the flavor of beer. The suitable high alcohol composition and content not only promotes the full aroma and taste of the beer, but also enhances the coordination and mellowness of the beer. When the higher alcohol exceeds a certain content, it will produce obvious smell of miscellaneous oil. Excessive drinking will cause discomfort to the human body, and the beer will produce a subtle bitter taste. If the higher alcohol content is too low, the beer will be dull. The wine is not full enough. Therefore, it is disadvantageous that beer contains an excessive or too low amount of higher alcohol. Under normal circumstances, high-quality ale beer, its higher alcohol content is controlled in the range of 50 ~ 90mg / L is more suitable.
Factors affecting the formation of advanced leaven
(1) Yeast species
Powdered yeast produces higher alcohol levels of 69-90 mg/L and flocculent yeast of 22-49 mg/L. High-yield yeast strains contain more high-grade alcohols, and appropriate strains must be selected.
(2) wort ingredients
Wort contains a sufficient amount of α-amino nitrogen and easily fermented carbohydrates, and the amount of higher alcohol formed by the synthetic route is small (the α-amino nitrogen content in the wort is controlled to be 180±20 mg/L), if the excipient ratio is too large Or adding more sucrose will cause the lack of α-amino nitrogen in the wort, resulting in an increase in higher alcohol.
(3) Yeast addition
(1.5~1.8)×107/mL is suitable, the inoculation amount is high, and the newly proliferated yeast cells are relatively small, which is beneficial to reduce the formation of higher alcohol. If the yeast cells multiply, the amount of amino acids required is large, and it is easy to form more high-grade alcohols. In actual production, the proliferation ratio of yeast is generally controlled within 4 times.
(4) Fermentation temperature
Excessive dissolved oxygen and high-temperature fermentation in wort can promote yeast reproduction, which in turn increases the amount of higher alcohol production. Therefore, it is possible to use low-temperature pre-fermentation and high-temperature reduction of diacetyl. Pressurized fermentation also helps to reduce the formation of higher alcohols.
(5) Fermentation method
The combined tank fermentation (pre-fermentation using a conical tank, post-fermentation in a conventional fermenter), the total amount of higher alcohol will increase by 20% to 25% compared to the ordinary fermentation method. Regardless of the method used, all measures to accelerate the main fermentation will increase the level of higher alcohol.
Edited by Alisa
2019.8.3
The term "higher alcohols" refers to a general term for alcohols of three or more carbon atoms, and is commonly known as fusel oil in the alcohol and liquor industries. Higher alcohol is one of the main by-products in the beer fermentation process and is an important substance that constitutes the flavor of beer. The suitable high alcohol composition and content not only promotes the full aroma and taste of the beer, but also enhances the coordination and mellowness of the beer. When the higher alcohol exceeds a certain content, it will produce obvious smell of miscellaneous oil. Excessive drinking will cause discomfort to the human body, and the beer will produce a subtle bitter taste. If the higher alcohol content is too low, the beer will be dull. The wine is not full enough. Therefore, it is disadvantageous that beer contains an excessive or too low amount of higher alcohol. Under normal circumstances, high-quality ale beer, its higher alcohol content is controlled in the range of 50 ~ 90mg / L is more suitable.
Factors affecting the formation of advanced leaven
(1) Yeast species
Powdered yeast produces higher alcohol levels of 69-90 mg/L and flocculent yeast of 22-49 mg/L. High-yield yeast strains contain more high-grade alcohols, and appropriate strains must be selected.
(2) wort ingredients
Wort contains a sufficient amount of α-amino nitrogen and easily fermented carbohydrates, and the amount of higher alcohol formed by the synthetic route is small (the α-amino nitrogen content in the wort is controlled to be 180±20 mg/L), if the excipient ratio is too large Or adding more sucrose will cause the lack of α-amino nitrogen in the wort, resulting in an increase in higher alcohol.
(3) Yeast addition
(1.5~1.8)×107/mL is suitable, the inoculation amount is high, and the newly proliferated yeast cells are relatively small, which is beneficial to reduce the formation of higher alcohol. If the yeast cells multiply, the amount of amino acids required is large, and it is easy to form more high-grade alcohols. In actual production, the proliferation ratio of yeast is generally controlled within 4 times.
(4) Fermentation temperature
Excessive dissolved oxygen and high-temperature fermentation in wort can promote yeast reproduction, which in turn increases the amount of higher alcohol production. Therefore, it is possible to use low-temperature pre-fermentation and high-temperature reduction of diacetyl. Pressurized fermentation also helps to reduce the formation of higher alcohols.
(5) Fermentation method
The combined tank fermentation (pre-fermentation using a conical tank, post-fermentation in a conventional fermenter), the total amount of higher alcohol will increase by 20% to 25% compared to the ordinary fermentation method. Regardless of the method used, all measures to accelerate the main fermentation will increase the level of higher alcohol.
Edited by Alisa
2019.8.3
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