Synergy and perception. Neither is easily measured nor explained, but they are vital parts of any discussion of hops. When brewers, breeders, farmers, hop processors, and, of course, consumers focus on any particular aspect of the hop, the effects ripple through the production process. This book could easily have started with the history of the plant or the chemistry involved, with a new season in the field, or with a brewer assembling a recipe.
Instead it begins with aroma, just like most current conversations about hops. The first chapter provides a primer on essential oils, the production of odor compounds, and how the human sensory system and brain turns those into aromas. There is no single formula. Brewers “want a checklist that matches oils and flavors,” said Peter Darby of Wye Hops in England. “It’s not that simple.” As scientists learn how the sense of smell works and connects with what we call flavor, it becomes even more complicated.
The second and third chapters examine the plant’s past and future. Were the book called Romancing the Hop it would include far more history. The plant has plenty of fascinating back stories, starting with the discussion in Chapter 2 about how it became an essential ingredient in beer. A complete history would amount to a volume more than twice this size; the Czech hop museum in Žatek fills 4,000 square meters and barely deals with anything beyond Bohemia. Histories of breeding, cultivation, and the trade could all be separate books. I would certainly buy one covering only landrace varieties, maybe one entirely about England’s Golding and its many sisters. Instead, the chapter details how hops emerged as a vital ingredient and the varieties that gained particular fame before plant breeding dramatically changed hop growing. Discussions about new hop varieties and the future naturally direct attention to hop breeding, the subject of Chapter 3. There’s much more to the lengthy process of getting a variety to market than creating “the flavor of the month.”
Chapters 4 and 5 focus on the farm, growing hops, then harvesting and drying them. Brewers call cones, or even pellets, hops, but the plant itself mesmerized Charles Darwin, following the sun as it climbs, growing up to a foot in one day. Because vegetative growth and flowering depend on day length, the plant flourishes only at certain latitudes, and more recently scientists have been able to explain why precisely where a variety is grown changes the character of cones themselves. The farmers’ work is not done until a crop is harvested and dried, and kilning is as important as any other stage of production in determining the brewing quality of a hop. Small breweries may not have the resources to send a representative to a hop growing region to pick particular lots of hops, but understanding the selection process is important. John Harris, who led the selection team at Full Sail Brewing for 20 years before leaving to start his own brewery in 2012, provides step-by-step directions for choosing the best hops.
Most traditional brewers use hops only in their “whole” form, either cones or pellets, although many now make an exception for CO2 extract. Chapter 6, The Hop Store, includes a summary of all the forms available to brewers and provides vital information about and descriptions of 105 hop varieties.
The hop arrives in the brewery in Chapter 7, the first of three that look at the chemistry of the hop; extracting, calculating, measuring, and understanding bitterness; the results of different additions throughout the brewing process; and ways brewers may maximize the benefits of using hops. The eighth chapter deals specifically with dry hopping, both how brewers add hops post- fermentation and all the variables they consider. Chapter 9 includes what Boston Beer Company director of brewing David Grinnell calls, “practical, unsexy details”-measures brewers may take to assure quality, the benefits hops provide in sustaining beer quality, and the possible pitfalls.
In Chapter 10 brewers provide recipes that illustrate how they use hops. To explore the role of hops in various styles extensively would take another volume and is a reason those styles merit their own books. Instead, the recipes that follow illustrate how a few brewers include hops within the context of what we really care about-beer. These include beers hopped with particular enthusiasm, but those looking for information about India pale ale, the style that has focused new attention on hops in general and aroma in particular, should consider IPA: Brewing Techniques, Recipes, and the Evolution of India Pale Ale by Mitch Steele.
In the late nineteenth century an uncredited English writer observed, “Fashion takes strange freaks, and it will be well for brewers to be prepared for all eventualities.” The future of hops depends not only on the future of beer fashion, but also on the way brewers communicate with the hop industry, further scientific discoveries, and other factors. Brewers who produce a relatively small portion of the world’s beer have made hops a bigger part of the beer conversation, but it could change again. There are no predictions about future fashion in the final chapter, but there are some thoughts from participants who will have a direct impact on “what’s next?”