Today was BY FAR the most fun and interesting day we have had. Talking to my classmates, this seems to be the way that everyone felt. We began talking about my personal favorite raw material: hops.
Our teacher for today and tomorrow was Mike Babb from Kalsec. For those not familiar with Kalsec products, they are the makers of advanced hop products, such as hop extracts. The extracts that they have developed have different qualities that brewers require in beer. Some of them are purely for aroma, while others are for bitterness. The benefit of the hop extracts is that they have the ability to be stored for much longer times without deteriorating than traditional hopping methods (pellets and whole leaf). In addition, they can be made to be light proof (say goodbye to skunked beers in clear bottles), and they can be added after fermentation to fine tune bitterness, flavor, and aroma.
In addition to talking about hop products, we discussed how hops are pelletized, how to store hops, and the different chemical reactions that occur when acids are isomerized in wort. We also talked about off-aromas in hops that can let us know when our hops are know longer suitable for brewing (the main one that people can easily smell is the old cheese aroma sometimes found in oxidized hops) and at the end of the day we did a "hand rub" evaluation.
The idea behind the hand rub is that you grab a handful of hops, rub them together in between your palms to create friction and release aromas, and smell the hops to try to detect any "off" aromas. We did the test with Citra (Very citrusy and floral), Pallisade (my favorite of the group, it had a unique apricot aroma), Crystal (very noticeably oxidized), Liberty (earthy and perfume like), Simcoe (Piney and White Grapefruit, obviously it was a high quality crop as there was absolutely no "Cat Pee" aroma) and German Hallertau (Spicy, Earthy, and also oxidized).
After the hand rub, we were done for the day and most of the class gathered in the Bierstube. While there, we had the opportunity to taste hop extracts and see their effect on finished beer. I added a small amount of 4 different extracts to samples of a Kolsch (Reisdorf). The hop extracts tasted surprisingly like what you would expect hop pellets to taste like. We had a dry hop example, a bitterness example, and a hop flavor aroma. The flavor and aroma were dead on for what you would think hops added to a boil or fermenter would taste like, while the bitter extract tasted very clean and didn't leave a lingering bitterness on the tongue.
We have our first test coming up tomorrow morning, so it is time to hit the books. I anticipate a late night of studying.