First Wort Hopping (FWH) is a hop addition to your boil kettle before you begin your sparge or lauter. At that point you sparge your mash tun with the runoff mixing with the hops that you added. It is as easy as that! The better question becomes, why use first wort hopping as opposed to a regular 60 minute bittering addition?
*Before I go any further into the subject, I will say this. There is a lot of scientific study into the differences between beers first wort hopped and ones that are not. All of what I am going to cover is my experiences using first wort hops and the subjective qualities that found from the resultant beers.
With that out of the way, on to the fun stuff. Typically, I use FWH for most of my beers and have no plans of stopping. FWH will give you a higher level of IBUs in your beer, however, the perceived bitterness will not be as high as a standard 60 minute addition. What FWH gives you is a smoother, more restrained bitterness and a significant contribution to the flavor of the beer, much like late addition hops. Due to this you need to plan your malt bill to follow suit. One of the numbers that I look heavily at is the GU:BU ratio, which is the ration of Gravity Units (GU) to your Bittering Units (BU). That number will give you a fairly good estimation of the malty/bitter balance of your beer. When using FWH, I tend to aim for a little higher on the scale than I normally would compared to using a regular 60 minute bittering addition.
One other thing to consider when using FWH is what hops work best with this technique. Since there is a significant flavor contribution to the beer, I typically use either aroma or dual purpose hops. Hops that I have found to work well include UK Challenger, Fuggles, Kent Goldings, and Perle. That being said, I have heard of people having success with high AA% hops as well. My only suggestion is to go out and try for yourself to see what hops and what proportions work well for you.
FWH works very well in all types of beer due to the softer bitterness that it imparts. The first experiment into FWH was by two professional breweries brewing a Pilsner style beer one with FWH and one without. Personally, I have found that FWH excels in lightly flavored, nuanced beers like Pilsners, Blonde Ales, Cream Ales, etc. FWH gives the beers the necessary balancing bitterness without imparting any harsh characteristics that would throw the beer off. I’ve also used FWH combined with another hopping technique, hop bursting, for a couple of high hopped beers (IPA, India Black Ale, India Brown Ale, etc.) with mixed results.
As I alluded to in my disclaimer, there is some dispute to how different FWH is from regular bittering additions and much of this is due to the inherent subjective nature of the ensuing analysis. FWH is an interesting hopping technique and one that I find a valuable addition to my brewing repertoire.
If you have not tried it, I urge you to do so at least once to see if you notice any differences. If you have, do you have any other tips/suggestions for using FWH?