What is “Dry-Hopping”?

Dry hopping beer is used to extract the hop aroma and flavour to give us that “hoppy” beer style we all know and love. Unlike using the traditional method of adding hops during the boiling phase, dry hopping adds hops during the fermentation or conditioning stages.

Pros and Cons

Pros of Dry Hopping:

• Essential Oil Preservation: By dry hopping, brewers can preserve the essential oils in hops that help create the flavours and aromas they want to achieve without the risk of losing them through heating.
• Flavor Enhancement: Adds distinct flavours and hop aromas to beer, making it especially suitable for hoppy beer styles such as Pale Ales and IPAs.
• No Bitterness: Unlike traditional boiling processes, dry hopping doesn't add bitterness to beer since the alpha acids in hops aren't isomerized into bitter compounds at lower temperatures.
• Complex Flavor Profiles: Dry hopping allows you to experiment with different hop varieties, resulting in complex flavour profiles such as tropical, fruity, or wine-like flavours.
• Intensified Aromas: By avoiding boiling, dry hopping extraction without extracts more hop aroma without removing their bitter and volatile oils.

Cons of Dry Hopping:

• Risk of Bacterial Contamination: Since dry hopping does not include boiling the hops, there is no sanitization involved. There may be a chance of bacterial contamination as a result. However, the environment created by hops and the active yeast often prevents bacterial growth.
• Astringency Risk: Prolonged exposure to dry hops can lead to the extraction of polyphenols, which can cause astringency, resulting in a drying or rough mouthfeel in the beer.
• Perceived Slick Taste: Some consumers believe that dry-hopped beers might have a slick taste, which might not align with their preferences or expectations.

Hop Form

When choosing between whole hops or pellets it’s important to keep these factors in mind. Whole hops used for dry hopping can potentially be reused in the boil kettle since their essential oils are preserved. Pellets, on the other hand, can only be used once.

• CO2 Purging: Whole hops can be more challenging to remove CO2 from due to their nooks and crannies, whereas pellets are smoother and facilitate easier purging of CO2.
• Pellet Density: Dry pellets come in various densities, affecting their behavior when they mix with beer. The density might influence whether the pellet floats or sinks and how it dissolves, but it doesn't seem to have a significant impact on the infusion rate of hop oils into the beer.
• This seems to be a decision of personal preference. Pellets can only be used once, whereas whole hops that are used to dry hop can be reused in the boil kettle because the essential oils have not been volatilized. 
• Dry pellets come in a variety of densities. The density affects the method of disbursement of the pellet when it mixes with the beer (floats or sinks, dissolves or powders or pebbles).

Whichever product you choose, the key is to measure your hops and choose the amount to add based on oil content rather than quantity.

Dry Hopping techniques

Dumping

A widely employed technique for dry hopping involves the straightforward action of introducing hops into the upper part of the fermentation vessel and sealing it off. While this procedure appears to be error-free, there are some potential drawbacks. Primarily, safety and the risk of oxygenation pose significant concerns. If the vessel's lid is not promptly and securely closed, it can trigger a hop eruption, a calamity that anyone who has witnessed it can attest to being far from enjoyable when it comes to cleanup and containment. Moreover, this approach necessitates a person to ascend a ladder (unless a scissor lift is at hand) to deposit substantial quantities of hops into the tank, thereby introducing a degree of risk, the magnitude of which hinges on the weight of the hops and the size of the ladder. Given that excessive oxygen exposure during dry hopping is undesirable, this method not only increases oxygen intake but also opens the door for airborne contaminants to infiltrate the tank. The inconsistency associated with this technique may result in uneven aroma distribution and essential oil integration, affecting the final product's quality.

Torpedo/ Gun

The torpedo or gun is a separate piece of equipment designed to make dry hopping more controlled and efficient.

The hops are loaded into a hop torpedo or gun, which is essentially a vessel or chamber designed specifically for this purpose. The hop torpedo is then purged with carbon dioxide (CO2) to create an inert atmosphere inside, limiting the hops' exposure to oxygen. The hop torpedo is then pressurized, and the beer is circulated or passed through the hop torpedo, exposing it to the hops.

This controlled method reduces oxygen exposure while extracting hop oils and flavours quickly. However, there are some drawbacks to using this method. The equipment is costly, and cleaning the hop torpedo takes time because it requires its own Clean-In-Place (CIP) pump and hoses.

Cannon

Dry hop cannons are classified into two types: bottom-loading and top-loading. Each has its own set of benefits and operational procedures, but the basic premise is the same: they deliver hops directly into the fermenting or conditioning tank, reducing the risk of oxygenation and hop volcanoes.

Bottom-Loading Dry Hop Cannon

A bottom-loading dry hop cannon is a piece of equipment that is attached to the tank's bottom. Pressurized CO2 is used to propel hops into the tank from below. Because CO2 acts as a protective barrier, this method is extremely effective in preventing the introduction of oxygen. The threat of hop volcanoes has been greatly reduced.

It is critical to keep an eye out for potential clogging issues during this process, as hops can sometimes form blockages. In such cases, multiple shots of CO2 and hops may be required to ensure uniform dispersion.

Top-Loading Dry Hop Cannon

Instead of being mounted on the bottom, the top-loading dry hop cannon is mounted on the top. While it provides convenience in terms of accessibility and does not require the use of specialized equipment for beer transfer. The main disadvantage is the possibility of oxygen exposure during the process, as the CO2 blanket is less effective when hops are introduced from the top. Brewmasters who use this method must be cautious about maintaining a low-oxygen environment and preventing bacteria and other contaminants from entering the tank.

MH-20 Hop Induction System

The MH-20 Hop Induction System greatly increases the ease and safety of the dry hopping process. Attached to select centrifugal or shear pumps, the MH-20 HIS hygienically suctions hops into your beer with minimal oxygen introduction. This completely eliminates the need for scissor lifts or shaky ladders, decreasing workload and greatly increasing safety. 

The MH-20 consists of a hopper, which resembles a funnel, that is connected to the front of a pump. Brewmasters can choose between our selection of high-quality centrifugal pumps or a shear pump, depending on their specific needs. Brewers can choose the level of shearing involved in the dry hopping process. Some may desire a more gentle blending, while others may seek a more intense shearing effect. The MH-20 system is designed to cater to these varying preferences, offering a range of options depending on the choice of pump:

Low Shear

When attached to a C216 or a Hyginox SEN-20 pump, the MH-20 system provides minimal blending and will pump your product into the tank as gently as possible.

Medium Shear

If medium shear is desired, a disintegration screen can be purchased and added to the C216, which can be installed directly into the pump.

High Shear

For brewers who require a more vigorous shearing and blending of hops, the shear pump option is available, chopping and blending the hops as they are added.

To initiate the dry hopping process using the MH-20 system, brewers add the desired quantity of hops to the hopper and seal it securely to prevent oxygen from entering. The system employs carbon dioxide (CO2) to purge the hopper, creating an oxygen-free environment to preserve the freshness and quality of the hops. As the beer is pumped through the system, the hop pellets are drawn into the beer, creating a harmonious blend of hoppy flavors. The mechanism responsible for this seamless integration is the "venturi effect" created by the narrowing of the pipe at the base of the MH-20 system, which induces a vacuum to pull the hops into the beer.

One of the remarkable advantages of the MH-20 system is its suitability for various brewing practices.

The MH-20 Hop Induction System isn't limited to dry hopping; it opens the door to a world of creative possibilities in brewing. Beyond hops, this system can be used to introduce a wide array of other ingredients into your beer, including berries, spices, cocoa nibs, and more. This versatility allows brewers to experiment with new and exciting flavors, offering endless opportunities for innovation.

By simplifying the dry hopping process, expanding ingredient possibilities, and offering customized shearing options, it empowers brewers to create exceptional and unique beers while ensuring the utmost control and precision in their craft.

Conclusion

In conclusion, dry hopping is a technique that contributes to the distinct flavours and aromas of hoppy beer styles. It is a preferred method among brewers due to the preservation of essential oils, the absence of bitterness, and the creation of complex flavour profiles. 

Dry hopping techniques such as dumping, torpedo/gun, cannon, and the MH-20 Hop Induction System provide varying degrees of control, efficiency, and safety. Each method has advantages and disadvantages, ranging from potential oxygen exposure to equipment cost and complexity.

The MH-20 Hop Induction System stands out for its ability to simplify the dry hopping process, improve safety, and provide brewing versatility. Its one-of-a-kind design makes use of the "venturi effect" and allows for customized shearing options. The MH-20 allows brewers to experiment with a wide range of ingredients, providing limitless possibilities for creating exceptional and one-of-a-kind beers.