Friday, December 3, 2010

The Art and Science of Hop Substitution Charts

We are often asked how the “Hop Substitution Charts” available on the web came about. There is some variation among them, but many appear to be carbon copies of each other.

What are they based on? Hop chemistry? Parentage? Sensory Panels? Educated guesswork? Test brews? Marketing sleight of hand? I asked my friends at OSU and the consensus was anywhere between “pseudo-science” to all of the above.

If anyone has any insights on the basis (or reliability) of the hop substitution charts (e.g., see http://www.byo.com/resources/hops) please let me know.

We aren’t so bold as to assert that one hop can be “substituted” for another – at least not without accurate genetic and sensory information. We prefer to say that one might present a suitable “alternative” for another.

When the hop “shortage” struck in 2008, many brewers scrambled to find substitutes for aroma hops. Many brewers tapped higher alpha varieties and to this day have stuck with them. One macro-consequence of this recipe change has been a decrease in the production and usage of aroma hops compared to pre–shortage years.

The recent New Brewer reported substantial decreases in the US acreage of workhorses such as Cascade and Willamette, while acreage in the “dual purpose” powerhouse Centennial has actually increased since 2008.

Based on anecdotal encounters with brewers, I’ve noted a trend towards simplification of the aroma hops used. It appears that while usage of public varieties, such as Sterling, Cascade and Mt. Hood has fallen, proprietary cultivars, such as Amarillo, Palisade and dual purpose Simcoe has gone up.

Of course, when a hop is proprietary, the owner can limit which farmers can grow it. The owner stands to obtain a licensing fee or royalty from the sale of the hop from the grower to the owner/merchant.

Random Sampling of Web-based Hop Charts:

Brew 365
Bitter Brewer
Knight's of the Mashing Fork
South Atlantic Home Brewer (Please note, this is a large .pdf file)


Since many of the hop merchants in Yakima also own patents on hop cultivars (e.g., Simcoe, Palisade, Citra, Amarillo, Warrior), it’s no secret that between public and their own varieties they’d rather push their own. That’s simply an illustration of the guiding hand of self-interest in a capitalist, laissez-faire economy.

But when each Yakima hop merchant pursues their own self-interest, is it true that Adam Smith’s “invisible hand” magically makes sure that hop varieties are fairly and propitiously allocated in a way that insures the march of the craft revolution?

Is the trend towards less diversity of the hop supply good for crafties? Is the consolidation of hop acreage in Yakima good for crafties? Should crafties rely on foreign imports when suitable varieties can be grown less expensively and more reliably in the US? Do crafties benefit when each year we see fewer heritage hop farmers willing to give it another go? Is the risk of over dependence on a narrow menu of varieties acceptable?

These are big questions. I’m sure the patent owners can make a strong argument that their hop inventions are unique and superior. There’s absolutely nothing wrong with owning patents. It takes years of R & D to bring home a winning cultivar – such as Citra. The question that intrigues us is not whether a proprietary hop is unique, but how unique is it?

That’s where the “substitution” charts come in. Within the framework of the aroma hops breeding program we sponsor at OSU, we will be looking at the design of a “sub” chart that is based on science and sensory analysis.

In the meantime, when brewers ask us for an “alternative” to Simcoe, we suggest Chinook, based mainly on the grapefruity aroma and the similar alpha acid profile (Centennial’s another choice). We’re not absolutely sure on parentage of Simcoe, since it’s proprietary.

It may be best to suggest blends of hop varieties to attain a particular character. As an example, it might be useful to say, “instead of Simcoe, use 50% of Hop A, 25% of Hop B, and 25% of Hop C.” Of course, as OSU continues to develop crosses in the pursuit of unique aroma hops, perhaps the day will come soon when the choice will be simple.

As we explore these questions, we’re always learning more from you about what works. Have you on a lark or hunch swapped out one variety (or blend of varieties) to imitate or, better yet, emulate a go-to hop? How did it go? We’d love to hear about your fortuitous trials and even your not so happy errors.

Roger Worthington
12/3/10