Blind Tasting Wine Secrets: Impact Compounds

Hey, what's up? It's Madeline. If you're interested in proving your senses, understanding the science behind aromas is a really fascinating thing to learn how to do. Not only you become better at, say, blind tasting wines or identifying secret ingredients in food, but you also have sort of a fundamental understanding of the physics of taste. And who better to really have a great knowledge of this particular topic are Master Samuel Yehs. They, in fact, spend several years training their palate to identify different aromas. A few days ago, I interviewed Master Samuel Yeh, Matt Stamp, about this particular topic, and he had some interesting tips for us for tasting wine. There's so many in wine, but there are only a few which are kind of characterized as impact compounds. So the idea is that an impact compound is an aromatic compound which you get in like only one or maybe a small select handful of varieties. Okay, so they're sort of like giveaways. Exactly, exactly. Telling their tales. Right, yeah. So, so Pirazine is certainly absolutely one, right? The whole Bordeaux family of grape varieties, Cabernet Sauvignon, Carmenere, Sauvignon Blanc, Cabernet Franc, all of those tend to have... And what do Pirazines smell like? They kind of smell like, you know, grass or maybe tarragon, or they have a vegetal kind of green bell pepper component to them, just kind of depending. They're, but again, it's not just one, it's, you know, it's not just one thing. Like there are different types of Pirazines, and the one that people tend to get in Bordeaux family varieties is called like, it's called something There's this other Pirazine. This is strange. Pirazine is actually something that's, and I gotta thank John Williams for this. Pirazine is something that is emitted by the plant as an insect repellent. Really? So, so it's an expensive compound, apparently, for the plant to produce. It requires a lot of energy. Right, right. So they just, they use it to keep insects away during a really like, yeah, but ironically, there's another type of Pirazine that is produced by ladybugs. And it smells awful, apparently, and people blame this Pirazine for ruining much of the 2004 vintage in Burgundy, because they said Asian ladybugs got into the tank. So it's the same thing. So apparently, they were also trying to keep what? So we got bug juice in the fermentation tanks. Right, yeah, totally. And it made the wine taste like butt. Totally, exactly. Right. So, so Pirazine, this is, this is one. Okay, so that's one. All right. And Pirazine exists, like all vines produce it. But for most vines, the amount that's left over, when you get to harvest is just like, yeah, it's like below our threshold of reception. But for if you've had that from Chile, that's, that's definitely like, it's, it's, it can be intense, right? Yeah. So Rotundon is another, or Rotundon is another kind of famous one. That's the peppery component of like Syrah, or some Gruner Veltliner, or a lot of Northern Italian kind of red grapes, like Escapatino and things like that. This same thing, Morved has this. Yeah, that black pepper note. Yeah. So you get it, you know, you get it in Rome wines a lot, you get it in, you know, some Northern Italian, Pella Verga, you know, super peppery red wine, super fun, peppery red wine. So other other kind of impact compounds. What about white wines? So with white wines, you know, Monoturpines are probably the big one. I mentioned this earlier when I was talking about how, like, they develop this aromatic kind of component to attract birds. Those are Monoturpines. And it's the same stuff that flavors like the shampoo you use, you know, and the soap you use and, and, and a lot of perfumes and things like that. They're the, these tremendously like floral or kind of fruity kind of compounds, you know, it's what gives a rose its smell or what, you know, so, so Gibbard's Tremenor or Viognier or Riesling or, you know, Albarino or certain Muscat grapes or all those kinds of things have this Monoturpine. It's so aromatic. Yeah, it is. And it's, it's funny, like, you know, those compounds exist before and after the grape is turned into wine, which is kind of weird. Oh, that's interesting because so the grape actually still smells like that too. Yeah, yeah, yeah. Because I noticed, like, when I taste Sauvignon Blanc grapes, they're nothing like Right, right. Sauvignon Blanc wine. Right, right. Totally. And, and so Sauvignon Blanc, you know, they have pyrazines, but they also have this other, this other impact compound, which we used to call them mercaptans. Now we call them thiols. And they're basically this class of sulfur compounds. And they are sort of exist in this kind of like locked, you know, form in the grape. And then fermentation kind of unlocks them. Releases them. Right. Oh, interesting. And so when you smell like, when you talk about like cat pee or guava or like, those kind of notes, you know, in Sauvignon Blanc or the black currant in Cabernet Sauvignon, or, you know, things like that, that kind of grapefruit rind you get in Gewurztraminer, that to me is always kind of like, Like Alsace. Right, exactly. Yeah, so good. So, so those are, but those, those are weird because they exist, you know, those aren't as much of an impact compound because that can be a lot of different grape varieties, just depending on kind of how they were grown. And then there are other things, you know, that, that, that, you know, that are more winemaking driven, like, you know, diacetyl, you know, you get that. Butter. Butter kind of thing. You get, right, like just swim in it, right? From malolactic fermentation, you get, you know, this thing called sodalon from oxidation, which is. Sodalon? I've never heard of that one. It's like, it smells like cumin or maple syrup or walnuts. Oh, I know this very well. Is that, is that sort of, I always associate that with Mallard Reaction. Is that sort of associated with. It is, but it's like in wines, you principally get it from oxidation. So wines like, like, like, you know, Olorosa Sherry or like Von Jon from the Jura or even like really old, you know, Chardonnays or things like that, or old Sauternes tends to have that kind of thing. So yeah, there are, you know, so this idea, like these impact, the impact compounds that we understand right now, there are really only a few, you know, and then there are all of these other like aromatic compounds in wine that are either less well understood or they form this kind of like base aroma of wine or, you know, and so that's, I think in the future, like getting into more of those and their, and how they influence each other, I think will be really interesting. So we're only just beginning to understand aroma compounds. Yeah, it'd be an exciting time to go back to school, I guess. Yeah. Anybody interested in microbiology?