Hoppers, hop guns, cannons, torpedos; is anyone else confused?
Hops have been used in beer for centuries but even today the jury is still out on the ideal methodology, which can make choosing your perfect hop induction system stressful. Dry hopping is a popular technique for adding aroma and flavour to hoppy beers. During dry hopping, the lack of a boil prevents the hops from volatilizing and the essential oils from evaporating out. This allows the essential oils to infuse with the beer adding aroma and flavour without additional bitterness. In this post, I’m going to break down the most popular dry hopping techniques and systems available today in comparison with our CPE MH20 Hop Induction System and talk about what you should consider before choosing the system for you.
What should be influencing your decision on which dry hopping system?
- Whole hops or pellets?
- Risk of oxygenation
- Safety concerns
- Do you want the hops agitated?
- Price range
Whole hops or pellets?
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. Whole hops can be harder to remove the CO2 from because of the nooks and crannies of the hop. Pellets are smooth and easier to purge the CO2 from.
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). In the study by P. Wolf, the disbursement did not appear to have an effect on the rate of infusion between the oil and the beer. It is still unclear whether whole hops or pellets are better, or even which pellets are better than others. No matter which product you choose, the key seems to be to measure your hops and choose the amount to add by oil content and not only by quantity.
When working with pellets you have the option to help them break apart. Pellets usually break down within 30 minutes; the exact amount of time depends on the density of the pellet. If you wish to accelerate the integration of the pellet you can shear the pellets. Shearing the pellets will increase the amount of surface area for a longer duration. High shear options (such as a shear pump or a blender style pump) will almost completely break down your pellets. Medium shear will start the process, but will not dissolve the pellets. For low shear use a normal centrifugal pump. There is no such thing as a shearless pump, but a traditional centrifugal will do minimal damage to the pellets. The sheer preference seems to be a personal choice of brewers.
Most brewers try to avoid allowing oxygen to enter their tanks, but with cheaper solutions, it's just not possible. Oxygenation negatively affects the chemical reactions that lead to the integration of the essential oils into the beer; oxygen can wreck even the best of brews. To achieve a consistent aroma integration, it is important to prevent oxygen from coming in contact with the product. To reduce oxygenation use a hopping system with a CO2 purge.
If you do not have a scissor lift (or an equivalent) but have a lot of hops to introduce, any method that requires one being on top of a tank, either to dump hops directly in or to load a hops system, is not recommended. It is extremely dangerous. If you are using a ladder and it is not clipped in it can tip causing the unfortunate brewer to fall. If the ladder is clipped in, but if the tank isn't installed correctly installed, the entire tank can be pulled over. Personal safety harnesses are also a necessity when dumping at the top of a tank.
Do you want to agitate your hops
The agitation of hops during dry hopping again tends to be of the preference of the brewer. If you let the hops sit at the bottom of the tank the dry hopping process can take weeks, the addition of agitation quickens the process. Some brewers pump their hops through a tank or outside device throughout the entire process, others create agitation within the tank, while others add the hops and then let them be. All of these methods are valid; it's your choice as to what you think tastes better.
Dry hopping systems all tend to get a little pricey. The more complex, the more expensive. Hoppy beers are growing in popularity and it is often worth investing the money to achieve the perfect aroma and taste. Separate units that the beer needs to be pumped through tend to be the most costly. Pumps with a hops integration system are usually a more affordable option. The most important thing to watch for is quality. If you are buying inexpensive equipment to ensure that it is classified for sanitary applications. It is key to make sure you trust your supplier, you don't want a failure to force you to dump an entire tank of beer.
The most common way to dry hop is to simply dump the hops into the top of the fermentor and close the lid. You might think this sounds idiot proof, but it is actually quite easy to cause an overflow. While being quite simple, there are a couple of issues with this method; the largest of which are safety and oxygenation. Firstly, if you do not get the lid closed and secured quickly you can achieve a hop volcano. Those who have experienced this phenomenon know that it is not fun to clean up or to stop. Secondly, this method requires a person to climb a ladder (if you don’t have a scissor lift) and dump pounds of hops into a tank, this can be quite dangerous (the magnitude of which depends on weight and ladder size). When dry hopping you do not want to add lots of oxygen, this method does, and it can allow bacteria and particles in the air into the tank. The inconsistency of this method can lead to an inconsistency in both the aroma and the integration of the essential oils.
A couple companies and breweries have designed equipment to help facilitate dry hopping. The hop torpedo or gun is one of the popular options. It is a separate piece of equipment that the hops are placed in, it is purged with co2 and pressurized before the beer is then run through the torpedo. They extract the oils and provide standardized dry hopping in less time. One concern is that recirculating your beer provides another opportunity to introduce unwanted oxygen. This equipment is nice and fancy, but expensive and time-consuming to clean; it requires its own CIP pump and hoses for cleaning. You also need to be using a pump to move the product to the torpedo and back during dry hopping. The biggest issues are the potential for oxygenation, space, cost, and cleaning.
There two main types of cannons, but the general premise of both is that they shoot the hops into the tank. The dry hop cannon attaches to either the top or bottom of the tank and uses CO2 to shoot hops into the tank. This removes the risk of both oxygenation and hop volcanos. The top-loading hop gun requires a scissor lift for larger quantities of hops. You do have to watch for clogging and often need to do multiple shots to get all the hops in, which requires a lot of CO2. This method allows the beer to remain in the tank you have chosen for dry hopping. The cannons are good for small breweries and smaller quantities of hops. They are sanitary, cheaper usually than the torpedo, fairly easy to use, and prevent oxygen, bacteria, and other unwanted contaminants from entering the system.
MH20 Hop Induction System:
Our MH20 Hop Induction System was designed to help alleviate some of the dangers and issues that arise when dry hopping. The hopper (funnel) is attached to the front of a pump (either one of our centrifugal pumps or a shear pump). You add the hops to the hopper and seal it (prevent O2 from entering) and then use CO2 to purge the funnel. As you run the beer through the pump, the narrowing of the pipe at the base of the MH20 creates a “venturi effect”, forming a vacuum that pulls the hops into the beer. The hop pellets and beer are mixed together as they are pumped into the tank. This is ideal if you are switching tanks to dry hop or if you recirculate your beer. It also eliminates the need for ladders and scissor lifts.
There’s a lot you can do with the MH20. If you need to add more hops you can use a bigger funnel. It can also be used to introduce other ingredients to your beer as well: berries, spices, cocoa nibs, etc.
Other styles similar to the MH20 chop or shear as they add the hops; some of our customers have requested a blending function, while others have requested as little shearing as possible. So, we decided to give brewers an option. Depending on your pump choice you can have low, medium, or high shear (there is no such thing as no shear when a pump is involved). If you attach the MH20 to a C216, C214, or a Hyginox SE20 there is no extra blending involved and they will pump your product into the tank as gently as possible. A disintegration screen can be purchased and added to the C216 that allows for medium shear (it is installed into the pump). Our high shear option is the shear pump, which chops and blends the hops as they are added. We have made it so that you can buy just the induction system if you already have one of the four compatible pumps. That way, you aren't forced to purchase a pump that you likely already have.
A big thank you to Iain at Strange Fellows brewing for the help!