From Field to Ferment, our experts discuss previous crop years

by | Aug 16, 2018

Yakima Chief Hops is on the hunt for some of today’s leading industry myths. With ongoing speculation surrounding the current state and future of hops, Yakima Chief Hops is committed to transparency regarding the rumor that hops from prior crop years are of poorer, lesser quality.

I conducted a round table interview with Yakima Chief Hops’ biggest experts on the topic of product production, quality, brewing and trends to dig deeper into industry assumptions and behaviors that detour brewers from hop products with older crop years.

On the panel were; Chad Roberts, Production Planning Manager, Missy Raver, Director of Quality Control, Tommy Yancone, Technical Brewer and Bryan Pierce, Director of North American Sales.

Alex: There seems to be some hesitation from breweries when it comes to brewing with hops from older crop years. From your perspective, can you explain why brewers feel like hops from prior crop years are of poorer quality?

 Bryan: Every year hop fields see different conditions. As everyone knows, some years have cooler springs, hotter summers, drought, floods and all sorts of different pest pressures. All of this can have a huge effect on hops, and sometimes the most recent crop can have seen more adverse conditions than one that’s two or three years older than it. Some brewers are very attuned to this and can tell you, “Yes, 2017 was a great year for Centennial,” or “2015 was an awesome year for Citra®!”

 Tommy: As with any agricultural crop, nothing is ever as fresh as when it’s harvested. Brewers believe the more recent their hops were on the farm, the better the quality they receive. That’s not untrue. However, Yakima Chief Hops is an expert in processing and sustaining quality, from farm to kettle, no matter what year the hops were harvested.

 Alex:  Over time, what factors cause the degradation of hops?

 Tommy:  As hops age, if they are exposed to oxygen and high temperatures, the alpha acids will begin to oxidize, which both lowers the bittering potential of a hop and creates compounds such as isovaleric acid—making hops smell “cheesy.” Luckily, we have multiple safeguards in place to ensure that our hops from previous crop years are still going to be excellent. 

 Missy: The key to quality hops are good practices at the farm, the right storage conditions, timely processing and strict processing parameters. Once stored in a controlled temperature zone, Yakima Chief Hops products can last more than three years without fluctuation in alpha, beta or HSI.

 Alex:  So, from the moment hops are harvested, they’re immediately at risk for oxidation? What does the timeline look like during harvest?

 Missy:  Yes, as soon as the bines are cut, the hop cones start to dry out. And as they dry, it causes them to open—exposing the lupulin glands to oxygen.  Because of this, growers harvest the fields and immediately transport to picking machines to remove the cones from the bine. The cones are laid into the kiln to dry.  Kiln drying takes 8-10 hours, then the hops are cooled in piles with a moisture range of 8.5-10.5.  After cooling, the hops get pressed into bales. The baling process flattens the cones and protects the lupulin glands from oxygen. If the hops are over dried, the cones will shatter during baling, exposing the lupulin.

 Tommy:  During harvest, we receive more than 35 million pounds of baled hops during a 6-week period. Our biggest concern during this time is getting the hops into our cooling warehouses. Since the hops are baled in plastic and kept cold on the day of arrival, we severely inhibit oxidation. 

 Alex:  What happens once all hop bales get into cold storage?

 Tommy:  For each lot that is delivered to our warehouse during harvest, we calculate the hop storage index (HSI). This is an analysis that estimates the rate of hop degradation. There are a lot of factors that can affect the HSI of a given lot, but much of it is variety-dependent. 

 Missy: When calculating HSI, we also analyze samples through our on-site lab. The ability to provide documented quality assurance to our brewing customers allows us to maintain our position as the leading hop supplier in both quality and sustainability.

 Chad: When it comes time to process the raw hops into T-90 pellets or Cryo Hops®, my team will try to process hops with a higher HSI first. Once the hops have been processed into pellets, they are extremely stable. 

 Alex:  Can you elaborate on that? What does YCH do to ensure continual stability?

 Missy: All our pellets are sealed in an oxygen-impermeable Mylar bag, which is thoroughly flushed with nitrogen gas. At that point, the pelleted hops are put back into our temperature-controlled warehouses before being shipped out to customers. If brewers continue to store the hops between 33-41 degrees, they should continue to produce great beer for years to come. 

 Chad:  During our processing of T-90 pellets and Cryo Hops®, we do everything we can to keep the hops as cool as possible, to prevent the oxidation reaction from occurring. In addition to the numerous times hops are sampled during receipt and processing, in 2016 we instituted an aggressive annual sampling regimen to check previous crop year analytical and sensory stability and conditions.  An overwhelming amount of product we checked was in excellent condition, with a standout 2010 Cluster lot having only lost 1% alpha in six years and I personally brewed with it and it tasted amazing.

 Alex:  As brewers, what is your experience brewing with various crop years?

 Chad:  Personally, I have some hops from 2013 I use regularly in my beers today and will continue to for the next few years. I find if the packaging is sealed and they are kept out of light, in cold storage, the quality won’t disappoint.  Tackling our prior year’s crop hop inventory is one of my primary goals as a Product Manager. Of the many granular minutiae that ultimately help determine a hop lot’s quality, crop year is one of the most unimportant if you deal with a processor you can trust.

 Tommy: If ever a brewer receives a lot from a hop supplier that they’re not happy with, it is always important to provide that feedback and why. A good hop supplier will always work on finding a solution that meets their needs.

 Alex:  Thank you. Does anyone have any final thoughts?

 Bryan: As Missy mentioned prior, it is always important to remember that hops are always at their best quality at the farm. As a supplier, it is our job to ensure we capture that quality the best we can as we process into other products so it can arrive at the brewery the same way. That is why being a grower-owned company is so meaningful. Also, programs like Green Chief® are so impactful on what a brewer is going to use in their brewhouse. It’s important to know that if hops do not meet our high standards, we will not accept them from growers. After all, the shelf life begins when the hops come off the bine.