May 7, 2018 | The Rare Barrel
In a continued attempt to expand our processes and knowledge, The Rare Barrel team decided to delve into the world of beer/wine hybrids. As we have steadily forged our way into the world of fresh and unpasteurized fruits, wine grapes inevitably became an ingredient of interest.
Before we made moves to actually get the grapes in hand however, we had to answer a few questions. We were going to combine two incredibly different fermentation processes, so it was important that we were thorough in our planning to ensure a unique and expressive product. After months of research and a load of information from our friends at other breweries, we came to a few simple questions that we needed to ask ourselves.
What varietals were we going to use?
How would we process the ingredients?
What beer would work best with wine grapes?
How would we ferment everything?
WHAT GRAPES? AND HOW DO WE GET THEM?
Due to a number of circumstances, there were some mild limitations on the varietals available to us. Our intent for a red wine hybrid was to truly showcase the fruit, which led us to lean toward the fruitier, jammier, richer varietals such as Pinot Noir, Syrah, Merlot, and Zinfandel. As for a white varietal, we specifically had our eyes set on Chardonnay. We have some phenomenal oak forward Chardonnay barrel aged beers in the cellar and we were looking to compound upon this character with the addition of grapes. Unfortunately, we were unable to source any fresh white wine grapes as we had started the search too late into the harvest season. We were also barred from tapping into our immediate neighbors to the north in Napa and Sonoma due to a series of devastating wildfires. Much of the remaining crop was either affected by smoke taint or destroyed outright, which resulted in a number of particular varietals becoming unobtainable. Fortunately, there are a number of other beautiful grape growing regions in Northern California which allowed us to follow through with the idea of using a local grape source. We eventually made contact with a vineyard in Amador County who was able to supply us with nearly one ton of incredible late season Merlot and Petite Sirah.
Our timing could not have been better, as we were able to clip the grapes just a few days before the first major storm of the fall. The sudden rainfall would have either caused rot or destroyed the fruit, ultimately ending the harvest season and closing our window. Pushing the harvest so late into the season however, allowed the fruit to ripen much longer on the vines than typical. This yielded a much higher sugar level, a more concentrated fruit flavor, and drier/less green stems. All of these factors helped contribute to an accentuated fruit character in the final product.
PROCESSING, PROCESSING, AND MORE PROCESSING
After harvesting the grapes came the processing. We at first attempted hand processing the grapes, which we quickly realized was an incredibly painstaking process that would have resulted in the fruit spoiling before we could finish. We decided to reach out to a local wine cellar who was kind enough to lend us their grape processing equipment. The crusher/destemmer made quick work of the ton of whole fruit and really saved the day for us. The fruit that we yielded from the crushing/destemming process provided us with the base fruit we would utilize for the majority of our wine/beer experiment.
As it was our first year using this fruit, we wanted to gather as much data as possible on its interaction with our beer. There were numerous methods through which we could have introduced the fruit into the beer, but we settled on utilizing three different fruit processing methods: purée, destem/crush, and whole cluster.
The degree to which we processed the fruit seemed to exhibit the biggest impact on the flavor of the final product. The idea of pureeing the grapes was both intriguing and worrisome; we felt that the pureed fruit would result in the best extraction, as the contact between the fruit and beer would be maximized. This maximized extraction however, could potentially pull out some of the less desirable characters from the wine grapes, such as tannin and astringency. In the end, the pureed grapes produced the juiciest, fullest, and most flavorful beer. None of the anticipated tannin or astringency translated to the final product and the fruit character was some of the most expressive we have ever experienced. The more traditional fruiting method of crush/destem worked well too. The crushed/destemmed fruit allowed us to pull strong fruit character without any of the harsher qualities of the grape expressing themselves.
Whole cluster fruiting was by far and away the most unique fruiting method we have attempted. Before we crushed/destemmed the bulk of our stock we set aside about 500 lbs. of whole grape clusters. We took a page from a more traditional method of wine fermentation and added whole clusters of the fruit (stem and all) to the beer. The thought process behind this method of addition was to allow the fruit to undergo a semi-carbonic maceration fermentation method. The theory we had for this fermentation method was that each individual grape would undergo its own internal fermentation, and as CO2 was built up, the fruit would burst and release its contents into the main body of the beer. This would allow for a steady flow of fermentables to work their way into the beer as it aged in the barrel, as opposed to the immediate flood of sugar introduced in a more standard fruiting method. This fruiting method seems to have created a more complex final product. Not only was there a noticeable flavor contribution from the stems, but the slower pace of fermentation seems to have helped promote the retention of some more delicate aromatic profiles.
EXPERIMENTS IN FERMENTATION
After fruit processing, we had to decide the types of beer we would ferment the fruit in. Again, to obtain a better understanding of the interaction between our beer and wine grapes, we chose a number of different bases to fruit. The first two base blends we settled on were a more standard approach to fruited beer. We utilized an aged blend (the typical approach we would apply to any other fruit refermentation) as well as a fresh/young mixed culture beer. As we were expecting a significant drop in pH and a corresponding increase in acidity, we tried to fruit blends that were less acidic than our typical bases. The acidity of the aged blend in particular was something we tried our best to keep in check, as an aggressive acid profile could end up masking the more delicate characteristics of the fruit. To our surprise, the resulting products picked up relatively little acidity even though an incredible amount of readily fermentable fruit sugar had been added. Both the aged and young blends ended up showcasing a pronounced fruit profile while maintaining the expressive, yeast forward foundation set forth by the base beers.
As aforementioned, the majority of the barrels we fermented were with a varied collection of mixed culture blends, and those more or less panned out as we expected. We did however, employ a number of atypical processes to ferment our beer/wine hybrids as well. One of the more unique fermentations we did attempt was a “natural,” fermentation process. We added the grapes to unfermented wort and let the naturally occurring yeasts on the grape skins take on the brunt of the fermentation tasks. Though there were a few days of lag before any noticeable fermentation took place, the beer eventually took off and has been aging nicely.
Another unique fermentation process we experimented with was open fermentation. We removed the heads from a number of our oak barrels, added the fruit, and racked beer on top. There are obvious risks involved with this practice as the beer is exposed directly to the open air, which could quickly lead to the development of undesirable off flavors. The pay-off would be a potentially more expressive and unique final product. We punched down the fruit twice a day for the first week and once a day for the second week. To mitigate the surface’s constant exposure to oxygen, we employed another strategy from the wine world and laid a small layer of dry ice on the fruit’s surface. This was done in hopes of creating a thin blanket of CO2 after the majority of the initial fermentation had ceased. Seemingly the layer of CO2 curbed the growth of acetobacter and yielded a fairly clear expression of yeast and fruit. Ultimately, the open fermentation has resulted in a beer that has expressive yeast character while retaining the grape’s intrinsic wine elements. Though it was one of the more involved methods, this beer actually reached stability before the others and was the first to be released.
These beers are the result of a collaborative effort and could not have been created without the kindness of our local community. We were fortunate enough to have the help our neighboring winemaking friends to accomplish the production of these beers. We’d like to give special thanks to John of Golden Leaves Vineyards in Amador County for providing such amazing fruit for us to work with. We would also like to thank Bob of Urbano Cellars for not only providing us with the machinery we needed but with priceless advice on our overall process. These beers took a lot of time to figure out and think through as we were attempting something quite foreign to us here at The Rare Barrel. We hope that the results are worth the effort and that we can share the products with everyone in the coming months.
Senior Cellar Technician