Those of you who have been hanging around cellars too long like me start sliging around terms like, "sparge," "bulldog," and, "malo," all of us sounding like we'recelebrating some antiquated form of "talk like a pirate day." I guess it's the way it goes no matter what industry or line of work you find yourself in. Eventually you just start using terms that only make sense to a few of the people around you.
Well, I'm about to let you in on the secrets of MALO.
What we mean when we use the shorthand "malo," is "malolactic fermentation," which in itself is somewhat of a misnomer. It's the conversion of malic acid, the tart acid found in abundance in apples and also grapes, into lactic acid, a softer tasting acid found in yogurt and other cultured dairy products. This conversion is carried out by a diverse group of microorganisms known as Lactic Acid Bacteria [LAB]. There are a few major genuses - Pediococcus, Leuconostoc, Oenococcus, and Lactobacillus. They all work to convert malic acid to lactic, but they tend to prefer different habitats, such as different pH levels, alcohol levels, and temperatures. This is kind of analagous to if Neanderthals, and a bunch of other hominids lived at the same time as us, ate the same foods as us, but we all lived on different continents or in different climates.
While LAB are present at all stages from grape to wine, their populations tend to change and decline during fermentation, mostly due to some voracious giants called yeast. (To a bacteria, a yeast is the size a mammoth would be to us.) It's hard to get a foothold when you've got these collosal creatures all over the place eating all the food and giving off toxic substances. This leads to a pretty large decline in LAB populations over fermentation. And when all the sugar has been consumed and the last yeast cell dies in a pool of its own wine, what you're left with is an environment that isn't a particularly great place for bacteria to live. It's pretty acidic, there's a high level of alcohol, and the yeast have generally eaten up most of the micronutrients necessary for life. Only a few specially-adapted types of LAB survive. Eventually, the dust clears, and the bacteria that are left start to build up their populations.
Of course, it doesn't always work like this. If a wine isn't acidic enough, the LAB will start building up their populations before alcoholic fermentation finishes, and will start consuming the sugars that remain in addition to the malic acid, leading to off-aromas-- yogurty, spoiled milk smells, in addition to vinegar.
Another issue that can arise is a lack of sulfur dioxide after the malic acid is completely consumed. If the pH is high and there's no added sulfur, certain strains of LAB will continue to consume constituent parts of the wine like citric acid and glycerol. If the baceria start consuming the glycerol, it can lead to extremely bitter flavors in the wine. If they start consuming citric acid, it can lead to high levels of a compound that tastes like movie-theater butter-- this is what is responsible for the buttery quality of certain Chardonnays. At high levels, however, it can taste rancid. And if they start to consume the tartaric acid present in the wine, it can turn the wine hazy.
But for the most part, the LAB do us a service in that they quietly and slowly do the work to turn what would otherwise be a rough and sour wine, and soften and refine it into something that we find much more palatable. We don't let them do it in all wines-- some tartness is refreshing in wines like Pinot Grigios and Sauvignon Blancs-- but a high percentage do go through malolactic fermentation. If you happen to be at the winery later this fall when our wines are going through malo, we'll let you give them a try and see what all the fuss is about.
There are a few tools in my harvest toolbox that I just can't do without. Sure, the press and the punchdown tool are invaluable, but sometimes it's an ingredient that really saves the day. And one ingredient that is really a workhouse around here is the enzyme.
What is an enzyme? As much as the image above might lead you to believe it's a pile of birthday present ribbon trash, it's actually a protein that helps catalyze a reaction-- that is to say, it helps speed up a reaction. We use a few different enzymes for a few different purposes. Most of the enzymes that we use in winemaking are derived from fungal sources-- cousins to the yeasts that we use for fermentation.
For white wines, we like to use enzymes to help with clarification. Grapes, like most fruit, have a percentage of pectin in their pulp. This pectin makes them slightly gummy and can get in the way of the juice settling properly. The enzyme effectively acts like a bunch of little dudes with scissors, and breaks up the long pectin chains. With those out of the way, the juice and solids can separate more quickly and thoroughly. As you can imagine, this also helps us later on down the line when it's time to filter-- with less large particles in the wine, it saves us a lot of time and filter pads.
For red wines, we're looking for a similar pectin breakdown, but we also want to enhance the extraction of color compounds and tannins into the wine. So we're looking for somethign that will also help break down the grapes skins a little bit. This can get tricky, because if you use too much enzyme, you can wind up just turning your red wine ferment into a disintegrated mess-- you still want the skins pretty well intact so you have something to press against when you press at the end of fermentation. That's the trick with enzymes-- you want to use just enough so they're effective, but not so much that you turn your fermentation into the consistency of applesauce. We're talking on the order of about 20 grams per ton of grapes.
That's the great thing about enzymes-- a tiny bit goes such a long way. If you come out to the winery during crush and see us pouring a little bit of this and that into the auger, feel free to ask which is the enzyme. Because we're almost surely using it.
Hi Everyone. Today is a special day for me. An anniversary.
I moved here to work at Aridus exactly one year ago today. My partner, Riley, and I rolled up to the home in Tucson that we'd left when I started my wine career, dog and the boxes upon boxes from our wine cellar in tow. It was 7 pm, and the sky was putting on one of those magnificent sunsets that take up the whole of the firmament out here in the Sonoran Desert. We let the dog out, and unloaded all the wine. When we were done, the sky had darkened and the stars were out. I drank a Pacifico and stuck my feet in the pool.
This year, though, I'm not drinking Pacifico. And I'm not just dangling my feet in the pool. This year, I'm cannonballing in, and I'm drinking rosé. But not just any rosé. I'm drinking the rosé that I made last harvest for Aridus. I don't mean to toot my own horn, but I really, really like this wine.
My favorite rosés are from France. But not just from France-- from Provence. But not just from Provence-- from Bandol. What is Bandol, you ask? Bandol is a region in France that is particularly known for its wines crafted from Mourvedre. They produce reds, and some of the best rosés in the world. The rosés must be at least 50% Mourvedre (though the best use more), with Grenache and Cinsault making up the rest of the blend. If you happen upon one, especially one from Domaine Tempier, I highly recommend you try it.
Or... you could drink ours. It's 68% Mourvedre, and 32% Grenache. We macerated on the Mourvedre skins for two days before pressing them off, and the Grenache we pressed immediately. We blended the juices shortly thereafter and started fermentation, long and cool. Fermentation lasted 15 days, at which point we chilled the tank down to arrest fermentation at 1.3% residual sugar. After settling, we racked off lees into 57% neutral oak, and 43% new French oak. The rosé stayed in barrel for 4 months before bottling. It's been in bottle for three months now, since we bottled it on February 23rd. And now it's drinking beautifully. Just in time to quench your thirst. Put down the Pacifico! I think you'll prefer this.
Here is my surefire recipe to become a winemaker:
Get a bunch of barrels and stack them up at least as tall as you are. Next, grab a glass and put some wine in it. Put on your favorite plaid shirt (if you don't have one, get one immediately), and if you're feeling formal, a thermal vest. Now get someone to take your photo against those barrels as you stick your nose in that glass.
Just kidding! But seriously, just do a google image search for "winemaker," and see how far that deviates from the picture I've painted above.
"How did you become a winemaker?" is a question that I get pretty regularly. It's not a particularly common job, and being from Wyoming, it's not like I grew up imbued in a rich wine tradition. (The first wine I remember enjoying was Blue Nun, if that gives you any indication. I was five years old, though, in my defense...) One thing I can tell you about the path to winemaking is that nobody's is ever really that linear.
So let's say you want to try your hand at winemaking. Where do you start? What resources do you need?
I'd recommend just starting. Get yourself five gallons of grape juice, a food-grade bucket, and a 5 gram packet of yeast. Visit the online WineMaker Magazine site, and check out their guide for newbies. Read through it, clean and sanitize your bucket, and give it a go. I think the first step is just realizing that you can pretty easily convert juice into wine. Taste the ferment along the way-- make notes as to what you're noticing as it progresses. When do you feel the first prickle of carbon dioxide? How do the aromas and flavors shift? At what point does it seem more like wine than juice? Is there any point at which you wonder if this is going to turn out at all? Share the wine with your family and friends and see what their impressions are. You probably won't make a world-class wine right off the bat, but remember-- this is an experiment and a learning experience. If something goes wrong, GREAT! You can figure out what happened and fix it next time. Maybe nothing goes awry, but you realize you'd like to target different flavors or mouthfeel. That's awesome. Keep a log with your notes, and find everything you can to ask a question about. Ask the questions and search for answers. Then try again using what you learned.
Books and online resources can really help you out. Pick up something like, Home Winemaking Step by Step, or The Home Winemaker's Companion. Scour the back issues of WineMaker magazine. Find an online Q&A forum and see who else is asking the questions you have.
Live people can be an excellent resource, as well. Check in at your local homebrew shop and see if a staff member has some ideas for you. While you're there, peruse the tools they have for sale, and ask what they're for. Buy yourself one-- a hydrometer and cylinder, or a fermentation lock, then figure out how to use it. Think about what you really wished you had during your first fermentation, and find the tool that fits the bill.
If you can't get the answer you're looking for at the homebrew store, why not try reaching out to an actual winemaker? Most of us (provided it's not our busy season) are happy to share our knowledge and experience with interested hobbyists. And our contact information usually isn't that hard to find, so you're generally only one search and a few clicks away from being able to send an e-mail or make a phone call. And by all means, when you have the time, go visit a winery! Schedule a tour, and ask away. Look at what's happening at a big scale, and think about how that might translate to your own set-up. At the smaller commercial operations you'll usually be face to face with somebody directly involved in the production of wine. If you come out here to Aridus, chances are it will be me or Dan, our cellarmaster, taking you through the facility.
If, at some point, you find that home winemaking isn't just a passing hobby, there are more than a few ways to get into the industry. One great way to gain hands-on experience and find out if this is really for you is to work a harvest. Wineries always need additional hands during harvest. You can find all sorts of positions listed on winejobs.com. Browsing through the listings will give you an idea of what the work entails. Apply to a few in your area and see what comes of it. You won't be paid well, but you'll gain a lot in experience. After you've made it through one harvest, if you're still loving it, find another harvest position in the other hemisphere. See firsthand what another winery is doing differently. Do this enough times, and you'll gain a solid grasp of winemaking during the harvest. Eventually you'll have the experience necessary for a full-time position, and you'll see what happens in the winery during the rest of the year.
Education is also a great way in to the industry. You'll take general chemistry, biology, and horticulture classes to build up a solid knowledge base, and then start digging deep into the specifics of wine. There are programs at community colleges that really focus on getting folks ready for the industry. And there are University programs that provide unprecedented access to cutting edge research. You can take a look at the curriculum and decide for yourself what will best suit your style and goals.
I'm sure there are many other inroads besides all these listed above. If you're interested, I really do think you should try it! It's fun at any scale, and much more within reach that most people think. Cheers!
Yeast are very complex little creatures. They're a single celled fungus, and the type that is primarily responsible for alcoholic fermentation is called saccharomyces cerevisiea. The inner workings of a yeast cell are much like those of our own cells, with similar internal structures that have great names like mitochondria, golgi bodies, and endoplasmic reticula. They really aren't that different than we are on a cellular level. The major differences are the way in which they get energy from their food source, and what they produce as a result. In a very basic sense, fermentation is how yeast get energy to live.
As important as grapes are themselves in wine aroma, the bulk of the aromas in wine arise through the fermentation process, that is to say, yeast take what is present in the grapes and convert it into aroma and flavor.
The major aromatic compounds that come from yeast action are organic acids, higher alcohols, esters and aldehydes. As yeasts go about the business of producing alcohol, it's not a linear process of sugar in alcohol out-- there are a number of steps that the sugar goes through and at each step an intermediary is produced. Some of these go on to become aroma compounds rather than alcohol. In addition, sometimes the alcohol reacts with one of the intermediary products to form an aroma compound. It's all part of a living system, and living systems tend to be pretty complex.
The major compounds that yeast are resposible in wine are volatile fatty acids, higher alcohols, esters, and sulfur compounds. With many of these compounds, the effect of their presence can be either pleasant or unpleasant depending quite a bit upon their concentration in the wine.
Volatile fatty acids include compounds like acetic acid, which is essentially vinegar, and octanoic acid, which can taste sweet and buttery, and they are the products of two enzyme systems in yeast. They can range from oily to rancid to sweet and back again.
Higher alcohols are formed through the interaction of amino acids and sugars, and can account for such aromas as marzipan, fresh grass, and flowers.
You may remember from our discussion on grapes that esters are responsible for general fruity aromas in wine. Yeast produce these through sugar byproducts-- from a reaction between alcohol and a compound called acetyl-CoA, or through an interaction between amino acids and alcohol. They can give the wine aromas like banana, violet, and pear.
Unfortunately, yeast also can produce sulfur compounds that can add an unsavory note to wine. If you've ever had a wine that smelled like rotten eggs, burnt ruber, onion, or boiled cabbage, you know what I'm talking about. Those are yeast-produced aromas, and they're all sulfur compounds. Luckily, properly managing the fermentation process can ensure that yeast don't produce these in levels that are detectable.
This is obviously a very compressed version of how yeast contribute to the aromas in your glass of wine, but barring getting too deeply into metabolism, I hope it has helped illuminate the important role that yeast have to play not only in producing the alcohol in wine, but in the development of the aroma and flavor itself.
We're finally coming to the close of our bottling season. Whew.
If you've been into our tasting rooms, hopefully you've gotten a taste of our recently released 2015 Cabernet Sauvignon, 2016 Sauvignon Blanc, and 2016 Rose. Allow me to give you a sneak peek of some of our upcoming releases...
2014 Petite Verdot
And stay tuned for more...
It's going to be a great summer!
Everyone would like to think that their wine is fermented grapes and fermented grapes only, but I'm here to break it to you: that's almost never the case. Luckily, I'm also here to elucidate what might have been added to the wine you drink and most importantly, why.
Which brings me to an ingredient that I am very passionate about. Sulfur.
More specifically, sulfur in the form of sulfur dioxide. Good old SO2.
SO2 is one of my favorite winemaking ingredients, because it serves a dual purpose in a wine solution. It is antioxidative, and it also inhibits the growth of microorganisms.
As an antioxidant, it works to block oxidative reations-- that is, the sorts of reactions that make your wine start to smell and taste like spoiled fruit.
As an antimicrobial, it helps prevent the growth of bacteria, molds, and yeasts that can grow in wine and turn it into vinegar, or otherwise spoil it.
It's true that SO2 can be toxic when ingested in high doses-- the number isn't exactly set in stone, because doctors don't want to kill people to find out where that threshold is. They think it's somewhere around 190 milligrams per kilogram of weight (or about 86 milligrams per pound). An acceptable daily intake is considered to be about 48 milligrams per day for a 150 pound person. To put this in perspective somewhat, your body produces about 2,000 milligrams of sulfur dioxide just on its own every day, and that's also about how much you urinate out.
How much SO2 we add to a wine depends on its pH (the concentration of hydrogen ions in solution), but as a general rule of thumb, we target about 35 milligrams per liter of wine. This works out to about 26 milligrams per bottle. So unless you're drinking a bottle of wine and more per day, you're probably not in a lot of danger of overdosing on SO2. And in all seriousness, please don't drink that much wine. Share some with a friend, or cork it up for the next day.
And to add another layer of perspective on SO2, it's in quite a lot of food products. Dried apricots can contain nearly 2000 milligrams per kilogram, and they're the reason that dried apricots are still a vibrant orange color, rather than a dark brown-- that's an antioxidation example for you. It's in sugar, salad dressing, bottled fruit juices. Mostly things that you want to consume in moderation anyway.
We add sulfur here in the form of potassium metabisulfite, or KMBS for short. In water, the potassium disassociates and you get an active form of sulfur. It's a powder, and we dissolve it in a small volume of hot water before mixing it into wine. Larger wineries might keep a tank of pressurized liquid SO2 on site, which can be released directly into wine in tank. For our purposes and size, KMBS makes the most sense for us. And we take into account the alcohol level and the pH of the wine to make sure that we're only ever adding the minimal amount necessary to be effective against microbes and oxidation.
I hope this has shed a little light onto sulfur use in the winery. If you've heard about some other ingredient in wine that you'd like me to talk a bit about, please feel free to comment and let me know. I'm open and taking suggestions.
Most of us have eaten a grape-- usually a table grape from the grocery store. If you're lucky enough to have visited a vineyard or an enterprising tasting room around harvest, you may have even had the chance to taste a wine grape. Neither of these experiences, however, really elucidates much as to how a wine made from the same grape will actually smell and taste. If an alien came to earth and was given each, I doubt it would deduce that one was derived from the other. Why is this?
First of all, let's talk grape berry structure. The three main components of a grape are its skin, its pulp, and its seeds. Different compounds are found at different concentrations in each of these parts of the grape.
What even is a grape made of? Seventy-five to eighty-five percent of a grape is water. Fifteen to twenty-five percent is sugar. Acid makes up half to one percent, and pectin accounts for about a quarter of a percent. Add these numbers up, and you have very little left to work with in order to distinguish one type of grape from another. Luckily, the compounds that account for the vast differences in the wines made from these grapes require very small concentrations for the human nose to detect them once they are released from their bound forms.
These aroma and flavor compounds fall into a camp known as secondary metabolites. These largest group of these are phenolic compounds. Phenolics are a diverse group, including tannins, which contribute structure and mouthfeel, anthocyanins, which give wine its color, and flavonols, which work in concert with tannins and anthocyanins to boost their effects. These are generally found in all parts of the berry. The role these compounds play in terms of flavor is that they are responsible for the bitterness and astringency of a wine. In total, these make up about 0.65% of a grape.
And finally, the really fun stuff-- the compounds that really differentiate one grape variety from another...
Terpenes are responsible for floral aromas in wines, most notably in Muscat varieties and their cousins. They have fancy names such as geraniol (which smells like geraniums), and linalool (which smells like roses). It doesn’t take a very high concentration of these compounds to tickle your nose. In fact, many ripe grape aromas are dominated by terpenes. They come in two forms-- free, which is just like it sounds, and-- glycosylated, which is a fancy way of saying "attached to a sugar molecule." When attached to a sugar, they don't have an aroma. When free, they do.
Pyrazines are the compounds culprits for vegetable-like aromas in wine, and their detection thresholds tend to be very low. They can be a good thing, such as in herbaceous New Zealand-style Sauvignon Blanc, or a bad thing, such as in Cabernet Sauvignon, which if picked too early, can be overwhelmed by green bell pepper odors.
Volatile esters tend to be accountable for the various fruity aromas you get when sticking your nose in the glass. They can smell like specific fruits like strawberries, peaches or even bananas, or can just contribute to a generally “fruity” bouquet.
Thiols are sulfur-based compounds that span a huge range of aromas from cooked cabbage and garlic to passionfruit and grapefruit. As you can imagine, they can be either a pleasant or unpleasant addition to the drinking experience.
Norisoprenoids are compounds that are derived from carotenoids, which play a part in photosynthesis. The two best known compounds in wine that are associated with this class are beta-damascenone, which is the primary aroma in roses, and also present in fruits like raspberries, and TDN, a diesel-type aroma, which is not a norisoprenoid per se, but tends to increase as carotenoids break down.
So now that I’ve overwhelmed you with wine science, why don’t you go fill a glass with your preferred alcoholic blend of esters and monoterpenes, with judicious splashes of pyrazines and thiols. I’ll meet you back here in a few weeks to talk through the role of yeast in wine aroma and flavor.