* What Strata tells us
* Hop quiz
* The Terra family
* Random observation
* Mac Hops turns to brewing
Welcome to Volume 10, No. 4. Hop harvest has begun in the Northwest. Fresh hop ales are already being poured. How could that be? I wrote about why there are questions about when “wet hop” season should begin and why those beers can still taste really good in October for Brewing Industry Guide.

STORAGE STABILITY AND VINTAGE DEPENDENCE
Last month I recommended listening to one of two podcasts with Tom Shellhamm and Cecile Chenot at Oregon State University. They featured information from two studies. One examined the aging of Citra, Cascade, and Centennial under commercial storage and the discrepancies between sensory quality and HSI classification. The other evaluated Strata across multiple harvest years, farms, and fields, focusing on terpene and polyfunctional thiol profiles. I already summarized the key takeaways from the first for Brewing Industry Guide in March. Here are the highlights from the Strata study:
– Strata is particularly rich in 3S4MP, with levels up there with Mosaic, Nelson Sauvin, Thora and Hallertau Blanc.
– However, concentrations varied by about five-to-seven-fold between certain harvest years and field combinations. It does not work to simply plug 150 parts per trillion into a formula to calculate the possible level of 3S4MP your Strata addition is contributing to a beer.
– From a chemical standpoint Strata displayed notable stability from year to year when stored properly (cold and in low-oxygen packaging).
– Oxygen is a bitter enemy of hop aroma. As expected, the most pronounced losses were observed in the monoterpene fraction when high-oxygen samples were compared to low-oxygen one, while sesquiterpene hydrocarbons remained comparatively stable. Among free thiols, 4SMP was the most sensitive, with concentrations deceasing by about 50 percent, while 3SH and 3S4MP lost 15 to 20 percent.
HOP QUIZ
What is the year exed out in this statement refer to? Taken from the annual BarthHaas Hop Report.
Starting with the harvest of [xxxx] the shift a buyer’s market could no longer be overlooked. Hop production again exceeded consumption. Further factors contributed to the situation:
