First Wort Hopping

This page is intended to do two things: first, to provide a brief summary of the original article mentioned by Dr. Fix, and second, to tabulate the results of trials of this procedure on a homebrew scale using data provided by myself and helpful net brewers. The summary of the article appears immediately below; if you wish you can jump from here directly to the Table of Trial Results.

I will do this in two parts: first, straight reportage, in outline form, on the contents of the article (any errors or omissions are mine); and second, some commentary elicited from various brewers in the HBD during March 1996. This is not intended by any means to be a comprehensive treatment of this topic; it is only a summary.

Part I. Summary of the Article

2. Experimental Procedures. Two different breweries produced the test brews, Pils types, that make up the subject of this article. The two breweries make a slightly different version of Pils. No mention was made in the article whether the beers were products of decoction or infusion mashes (see comments below). At each brewery, the FWH beer was brewed with a reference beer alongside. The FWH and Reference beers at each brewery were done under controlled conditions, identical ingredients, pitching rates, etc., and differed only in the way they were hopped. The reference beers were hopped in the customary fashion for the two breweries under consideration, namely with two late-kettle additions. For the FWH beers made in both test breweries, the hops that would have been used in these late-kettle additions were instead dumped into the boiler once its bottom was covered with wort; no stirring--they just sat there while wort was sparged on top of them. Brew A (total hopping: 13.0 g alpha acid per hectolitre of cast wort) was first-hopped with 34% of the total amount added--Tettnang and Saaz that were typically used in aroma additions at the end of the boil under normal conditions. Brew B (total hopping: 12.2 g alpha acid per hl wort) used only Tettnang, but 52% of the total hop amount was used as First Wort Hops. No late-kettle aroma hopping was done in either brew. Brew A was boiled for 90 minutes and Brew B for 80 minutes, both at atmospheric pressure.

3. Tasting panel results: the FWH beers were overwhelmingly preferred over the reference beers in triangular taste tests (i.e., each taster was given three beers, two of either the reference beer or the FWH beer, and one of the other, and had to correctly identify which two were alike before their preference results were incorporated in the database). 11 of 12 tasters of each beer preferred the FWH beer. The main reasons given for the preference: "a fine, unobtrusive hop aroma; a more harmonic beer; a more uniform bitterness."

4. Analytical results--bitterness: The FWH beers had more IBUs than did the reference beers. Brew A: Ref beer was 37.9 IBU, FWH beer was 39.6 IBU. Brew B: Ref beer was 27.2 IBU, FWH beer was 32.8 IBU. This should come as no surprise, since more hops were in the kettle for the boil in the FWH beers than in the Reference beers. Prior to fermentation, the worts from both breweries showed the following features: the FWH wort had substantially more isomerized alpha acids, but less non-isomerized alphas. This was particularly true of Brew B, which had a higher proportion of first-wort hops. Nevertheless, the bitterness of the FWH beers was described as more pleasing than the (slightly weaker) bitterness of the reference beers.

5. Analytical results--aroma: For the aroma compounds, very distinct differences were measured (gas chromatography) in both the identities and concentrations of the various aromatic compounds between the FWH beers and the reference beers. Because the precise nature of the effects of aromatic compounds on beer flavor are very complicated, it cannot be said with certainty just why the various measurements resulted in the overwhelming tasting preference, but clearly something is going on here. Even though the reference beers had higher *absolute amounts* of most of the aroma compounds, again the FWH beers got higher ratings for overall pleasure.

6. Final comments: each brewery needs to experiment with its own setup for determining what sort of first-wort hopping is best for it. But the alpha-acid quantity should *not* be reduced, even if one gets more bitterness than one would get in the usual way. The tasting panel results seem to indicate that the bitterness in the FWH beers was fine, and mild--i.e. there is little harshness that can appear in a highly bittered beer. If the hops are reduced to compensate for the extra IBUs one gets from the first-wort hops, then the whole benefit of doing it might be lost. The recommendation is to use at least 30% of the total hops as first- wort hops--basically, this means adding the aroma hops as first-wort hops rather than late kettle additions.

To quote the article:

"...But we recommend that first wort hopping be carried out with at least 30% of the total hop addition, using the later aroma additions. [New paragraph] As far as the use of hops is concerned, the alpha-acid quantity should not be reduced even in the case of an improved bitterness utilisation. The results of the tastings showed that the bitterness of the beers is regarded as very good and also as very mild. A reduction of the hop quantity added [to compensate for the presence of more hops early in the boil--this note added by Dave, it is clear from the context of the preceding paragraphs] could result in the bitterness being excessively weakened, and the good "hop flavor impression" could be totally lost."

Part II. Some subjective comments

Eric pointed out George Fix's assertion that the best aroma comes from dry hopping. Although I am inclined to agree with this, what is "best" is subjective--there are hop heads and there are malt heads, and not everyone will agree on what constitutes the "best" hop aroma. Jim Busch commented on the very different hop character that ensues from the various procedures--kettle additions, whirlpooling, dry-hopping--and noted that pils beers are among the most complicated in terms of the delicacy and impact of hop bitterness and character.

Tracy asked about whether IBUs corresponding to the FWH addition should be subtracted from the total, and noted that with high-alpha hops one would of course get more bitterness. The hops used in the reported beers were Tettnang and Saaz, both low to medium alpha varieties. No comments were given in the article for use of higher alpha hops. However, because the results were discussed in terms of mg of iso-alphas per unit volume of wort and percentage of total hops added as FWH, there is at least the implicit suggestion that the concepts are general; that is, if one was using high alpha hops, then less would be used anyway in order to achieve a given bitterness. Obviously one must apply some common sense and knowledge of one's own setup to this. Eric Miller reported his experience that using very high-alpha hops as FW additions increased his bitterness more than he wanted, for example. Jim Busch commented that so far, because FWH has been used only in pils beers, where late-kettle additions are almost always with noble. low-alpha hop varieties, that it is quite justified not to subtract the IBU contribution of the FWH from the total target.

Several HBDers commented on the differences to be expected in FWH beers that were produced by infusion vs. decoction mashing. Briefly, decocted beers in general produce less hot break as boiling commences because of the decocts having been boiled already during the mashing procedure. In contrast, this earlier boiling has not taken place in infusion mashes. Accordingly, the reduction in bitterness that results from alpha-acid uptake by coagulating hot break would be more pronounced in an infusion-mashed wort than in a decoction-mashed wort. This might bear on the question of subtracting IBU contributions from FWH additions. My pure speculation is that this effect might be most noticeable when using high-alpha hops.

Tracy also expressed confusion that the level of bitterness should affect the perceptions of aroma and flavor. It does seem counter-intuitive. It would seem that despite this, there is in fact an effect, and as noted by both the Brauwelt authors and by Dr. George last year, the complexity of the aroma producing reactions is immense and no one fully understands why it appears to work the way it does.

Email me your questions and comments, praise and criticism--or just let me know you were here.