Due to the number of exceptional craft breweries in our region, farmers continue to plant acres of hops. Over the past several seasons, hop growers have become frustrated and brewers disappointed as hop yards are harvested too early. More often than ever, brewers and their consumers value aromatics over bittering flavors. We know that the bitter hop resins develop before aromatic qualities in hop cones. Northeastern growers are currently harvesting for bittering attributes of hops rather than waiting for aromatic essential oils to develop. It is clear that hop harvest dates developed for other production regions are not appropriately timed for our climate.
The goal of this project is to improve the quality of hops grown by local farms and bought by local brewers. A brewer survey early in the project will help us to identify which compounds/aromas brewers are most interested in. Then, on three farms (two in NY, one in VT) we will collect hop cones for full chemical analysis on three different dates as they mature in the field during both 2018 and 2019 harvest seasons. With three farm and three brewer collaborators, we believe that this project will strengthen relationships between northeast hop growers and craft brewers. We will hold three grower-brewer sensory evaluation workshops where hops harvested on different dates are ranked. Without regional, scientifically-based knowledge of when hops reach the maturity that craft brewers desire, growers will be left with off-flavored hops that have no sustainable, local market.
Our overarching goal is to improve the quality of hops grown by local farms and bought by local brewers.
Objective 1. Identify and quantify when resin and essential oil compounds develop in Cascade hop cones. Indications of success will include closely matched oil levels to those of other regions, fully developed citrus aroma, and satisfied brewers.
Objective 2. Understand which compounds and the quantity of each that local brewers look for in a lab report when making hop purchase decisions. If successful, growers will know which compounds and what level of each is considered high quality in our region.
Objective 3. Educate growers by disseminating our findings at 3 grower-brewer sensory evaluation events (2 in NY, 1 in VT), 2 annual hop conferences, 2 recorded webinars, and outreach materials printed for events and posted on the UVM Northwest Crops and Soils (NWCS) and Northeast Hops Alliance (NEHA) websites. Pre and post “quizzes” will indicate knowledge learned over the course of this project.
Hop cones form in late July and develop until they are harvested in late August through the end of September. Inside the cone, there are modified trichomes (leaf hairs) called lupulin glands. As the cone develops these glands start to fill with chemical compounds which include both resins (alpha and beta acids) and essential oils (Oliveira and Pais 1988). European work conducted in the 1980s, indicated that resins develop in the hop cone first, followed by essential oils. If a brewer is looking for more aromatic qualities in their final product, they will select a hop that has matured longer on the bine (Sharpe and Laws 1981). Now more than ever, brewers in the northeast value essential oils to create “citrusy” and “juicy” IPAs that are flying off the shelves. Specifically, New England brewers have received praise for their new style of aromatic beer which is now nationally recognized. Called a “New England IPA,” they have established a new style of beer (BB Magazine 2017). If local hop growers are currently harvesting when resins have developed but essential oils have not, how can they meet the demands of local brewers who require the aromatic qualities of essential oils?
Several studies conducted by the project leaders have contributed to the re-emergence of the northeast hop industry over the past six years. While hop harvest quality has been measured throughout these pest management framed projects (NESARE GNE12-033, NE IPM 027269), essential oil levels were not collected. The resin data collected was one snapshot in time when hops were harvested. The ongoing NESARE hop nutrient and pest management project (LNE16-348) does not include a study of hop harvest timing. Steve Miller, NY Hop Specialist, has worked with Rich Michaels, head brewer at Saranac Brewing, to compare chemical profiles of hops grown in NY state to those bought in from the PNW. This work has shed light on the variability and potential high quality of hops grown in the northeast (Cornell Hop Conference 2016). However, this work has been a survey of hop quality on many farms rather than a scientific assessment of when compounds develops here. Farmers require replicated readings of hop resin and essential oils from more than one growing season to be able to identify when their hops are ready to harvest. Furthermore, Extension specialists in at least 12 states nation-wide are conducting hop variety trials. To our knowledge, through our participation on the NCIPM Great Lake Hop Working Group, these programs have not identified regionalized hop harvest dates that highlight the best qualities of their hops based on local environmental factors and brewer input.
Hop harvest timing depends on multiple on-farm factors such as disease and insect pressure, irrigation, fertility, soil type, and canopy humidity. In the PNW, date ranges have been developed for specific regions and even individual farms (Crosby Hop Farm, personal comm.). Here in the northeast, smaller growers cannot afford to ship several samples overnight to Yakima, WA for analysis before harvest, nor can they afford their own on-farm labs. Therefore, they rely on hop cone moisture content in conjunction with sensory observations to determine when to harvest. Moisture content varies dramatically depending on relative humidity and farm management practices throughout the season. Visual and olfactory clues are helpful, but subtle and difficult for our untrained senses to pick up.
We have modeled this project after hop harvest timing work conducted by Oregon State University. Sharp et al. 2014 measured hop chemistry development in cones collected from two farms located in the Willamette Valley, Oregon. By measuring resins and essential oils at three-time points during cone maturation, the researchers were able to show that resins remained unchanged through maturation while essential oils significantly increased over the course of their 3 week sampling period in the field. Importantly, this study used brewers’ sensory evaluation in addition to lab reports to understand which compound levels produced the desired aroma in the end product (Sharp et al. 2014). Our project will similarly take several chemical profile readings as hops mature in the field. We hope to educate both growers and brewers on the environmental factors that influence hop chemistry development and the use of essential oil analysis as a harvest determination tool.
Cascade hops from three northeastern farms were collected and analyzed in 2018. The three farms who have agreed to be a part of this project are Borderview Farm in Alburgh, VT (latitude: 44.9°N, 73.3°W), Cold Spring Hops in Granville, NY (latitude: 43.4°N, 73.2°W), and Kinderhook Creek Hop Yard in Chatham, NY. Each farmer will manage their hop yard according to their standard growing practices.
Each farm received a visit in May or June to identify hop bines that would be used for the research trial. Steve and Heather remained in communication with the hop growers to learn when they estimated they would start harvesting. A sample was collected one week prior to their estimated harvest date. A sample was collected when they harvested the Cascade hops. The identified bines were left uncut and sampled one week after the hop producers harvested their hops.
Each sample will be 150g of wet hop cones were shipped to Alliance Analytical Laboratories (AAL), 179 Randall Street, Coopersville, MI 49404, overnight.
In addition to these shipped samples, Steve and Heather dried and processed one Cascade hop sample (1 kg) from each collection date from each farm for the sensory evaluation events using a food dehydrator and vacuum sealer. These samples were dried, labeled, and stored in a freezer.
There were some issues with the samples collected in both states. AAL did not receive an adequate sample size of some hops from some of the NY farms for analysis. Some of the VT samples molded while at the AAL. In NY, composite samples were prepared for blind sensory analysis activity. Laboratory analysis results for some of the NY samples were received and printed for the sensory analysis.
Due to not having enough samples analyzed in 2018, we will wait for more sampling to share any quantitative results.
Education & Outreach Activities and Participation Summary
One meeting was set up at Emporium Farm Brewery to bring hop producers and brewers together to review the analyses and to perform a sensory evaluation. Brewery Extension Associate Kaylyn Kirkpatrick attended the meeting to guide participants through the understanding of the analysis results and to coach what to look for in the sensory analysis. After all of the participants had a chance to complete the sensory evaluation, Kaylyn and Steve Hadcock lead a discussion on what the participants felt about the process.
One farmer reported that they feel they have a better understanding of the importance of harvesting hops in a timely manner. They also reported that they now feel more confident on how to know when it is the best time to harvest their hops.l
As a result of the webinar, do you feel better prepared to harvest your hops on time? 100% (13/13)
As a result of what you learned, will you make a change in your current hop yard? 69% (9/13)
August 2018- Pest and disease scouting, harvest timing
As a result of this goScout:
29% of growers planned on adjusting their harvest timing.
29% of growers planned on adjusting their pesticide applications.
42% of growers planned on making no change.
As a result of participating in this grant, have developed a working relationship with Roger Savoy at Emporium Farm Brewery. Have also developed a working relationship with Kaylyn Kirkpatrick. Kaylyn is Brewing Extension Associate, located in Geneva, NY.
Some of the samples could not be analyzed, due to not enough hop being submitted. Will revise the method used to process the sample for analysis next year.
Will send samples to the Cornell Agritech next year for analysis. This will reduce the shipping time, which will allow the samples to arrive a little fresher.
This research is critical to help hop producers have a better understanding of when to harvest their hops. Each growing season is different. Therefore, need to conduct several years of research to help better learn when hops in the Northeast should be harvested.