First, oxygen, oxygen is the number one enemy of hops. Oxygen can make alpha acid oxidative polymerization, lose the original taste and anti-corrosion ability, polymerization

First, oxygen, oxygen is the number one enemy of hops. Oxygen can make the alpha acid oxidative polymerization, lose the original taste and anti-corrosion ability, the polymerization of hard resin such as gamma resin is one of the main sources of bitter taste after hops. High molecular polyphenol in hop polyphenol will bring rough bitter taste to beer after oxidation. After the aroma substances in hops are oxidized, the aroma characteristics of hops will disappear or change, but sometimes the oxidized hops will have obvious Ester fragrance. In order to isolate oxygen, vacuum or nitrogen-filled packaging is often used now. Vacuum Packaging: hop particles, especially those with high oil content, will be compacted into a whole, very strong, not easy to break, inconvenient to use, and useless to see. At present, this kind of packaging has become less and less. Nitrogen-filled packaging: there is a large amount of nitrogen in the aluminum foil bag, and there is no adhesion between hop particles. It is convenient to use and is currently the most widely used packaging form. Preservation method of beer houses: at present, hops that can be purchased in large quantities are usually packed in 5 kg/bag, while domestic ready-made equipment is difficult to use up in a short time, therefore, it is recommended to divide the hops into N small packages immediately after receiving them, and take one bag at a time. Can use aluminum foil bag vacuum, can also use aluminum foil bag filled with nitrogen or carbon dioxide. Inflation can be used to top out the air in the package and then seal it. Oxidized hops: it can be added as a small amount of fragrant flowers at the end of boiling in wheat brewing. 2. Temperature the storage temperature of hops is recommended, and the upper limit is not higher than 4℃. Alpha acid begins to attenuate obviously above this temperature, and γ resin is polymerized to produce bitter taste, which affects the quality of hops; The lower limit is not required. Low temperature is conducive to maintaining the original quality of hops. When below 0 ℃, the shelf life can reach up to five years. The disadvantage of freezing far below 0℃ is the change of hop shape. Hop particles themselves contain about 8% of water. Once the water freezes and expands, the particles will become scattered and oxidize very quickly after contacting air. So it is recommended to save the temperature at 0-Between 2 degrees Celsius. It is suggested that the hops should be packed into small packages at low temperature to avoid the crushing and oxidation of particles in large bags when taking the hops. Others: Damage caused by high temperature to imported hops generally occurs during transportation. Hops are transported from abroad to China through the cold chain, which basically has no effect. Delivery by express or Debon, the time limit will be guaranteed. However, in summer and autumn, the national temperature is generally high, and express delivery needs 2- 3 days will have a significant impact on hops, so it is best to purchase hops in spring and winter. Third, light and light will make the hop color turn gray white, and the aroma components are lost a lot. Alpha acid polymerizes to generate gamma resin, which produces bitter taste. Therefore, at present, hops are all packed in aluminum foil bags. The act of storing hops in a transparent ziplock bag, although I have done it several times (Self-use not for sale), I still want to say, very low, very layman. If there is no aluminum foil bag, it can be solved by wrapping it with transparent ziplock bag and black paper. Four: humidity hop storage environment, relative humidity should not be higher than 60%. Excessive humidity leads to: 1. Α acid polymerization to generate γ resin, which produces bitter taste; 2, moldy bacteria, wine flower can kill most of the Gram-positive bacteria, almost no killing effect on Gram-negative bacteria and fungi; 3, decay, plant tissue in the environment of sufficient water, decay is inevitable. Company website: tranogroup. COM