The purpose of adding hops in beer brewing is various, mainly including giving beer unique flavor, refreshing bitterness, increasing the anti-corrosion ability of beer and improving the non biological stability of beer.

First of all, hops can give beer unique flavor. Many compounds in hops, such as essential oil, bitter substances and polyphenols, can bring unique aroma to beer. For example, some compounds such as prochloraz and hemp ketone can give the aroma of beer herbs, while some other compounds can give the aroma of beer fruits or flowers.

Secondly, hops can increase the bitterness of beer. In the brewing process of beer, α - acid in hops is dissolved in water during the boiling process and combines with protein in liquor to form bright yellow substance, which is the source of beer color. At the same time, the α - acid of hops also has bitter taste, and its dissolution in liquor will increase the bitterness of beer. The content and composition of α - acid in different hops are different, so the bitterness of different varieties of hops is also different.

Third, hops can also increase the anti-corrosion ability of beer. Some compounds in hops, such as hops, have antibacterial, anti-inflammatory and antifungal effects, which can inhibit the growth of microorganisms and prolong the shelf life of beer. In addition, some bitter substances in hops such as α - acid can also inhibit the growth of microorganisms.

Finally, hops can also improve the non biological stability of beer. Some components in hops, such as hops, can combine with proteins in wort to form larger precipitates, which will solidify and precipitate at the bottom during cooling, making beer clearer. In addition, other ingredients in hops, such as pinoresinoic acid, also have anti-tumor, antibacterial and other effects, and are also helpful in preventing cardiovascular diseases.

In addition to the above purposes, the addition of hops can also increase the biological stability of wort and beer, as well as the foaming and foam holding properties of beer foam.

In short, the addition of hops is a very important step in the brewing process of beer. It can not only endow beer with unique flavor and refreshing bitterness, but also increase the anti-corrosion ability and non biological stability of beer, so as to improve the quality and taste of beer.