Movin’ On Up: A Beginner’s Guide to Winemaking Using Whole Grapes

Using a kit is a great way to make wine. No special equipment is necessary, except maybe a carboy, airlock and food grade hose to siphon the wine to clear the finished wine. The juice is already balanced when it comes to you to correct the acidity and sugar level. You just have to reconstitute the concentrate in the proper ratio and add the re-hydrated yeast. Your additives are included along with detailed instructions. What’s not to like? I started my winemaking passion with a kit and enjoyed the finished wine. After a year in the bottle the wine, in my case Chilean Cabernet, improved markedly. But I soon wanted more control over the wine I made.

Many of us who start with kits are drawn to the next level: exploring the challenges and pleasures of working with juice, either white or red, which comes to you as nature made it. Though some juice is concentrated to reduce shipping costs, it does not come with instructions, additives or guaranteed sugar levels. But it comes with more opportunities to create the wine that you enjoy drinking, rather than fashioned to the perceived taste of the average consumer. And if you buy the juice directly from a local producer, you know where it was produced, how it was grown and often the grower’s testing for sugar and acid levels. This allows you to step up your ability to craft a wine, with perhaps only minor equipment additions, such as a hydrometer to measure sugar and a simple PH meter to assess acid levels.  

But juice still has its limitations, especially in making red wine. Most of us still buy the raw juice for most whites, with the exception of those aromatic varieties, where the maker wants to control the amount of time the juice is in contact with the skins of the white grape. These varieties include Riesling, Gewürztraminer and Sauvignon Blanc.

For red wine, the color, aroma and flavors of the varietal derive mostly from the skins. To craft a great red wine with true terroir, it is vital that whole grapes are used, crushed with the skins. This article will discuss how to accomplish a red wine from whole grapes without needing to purchase expensive winery equipment, such as a de-stemmer, crusher or even a grape press. You can do this at home and without a net, but maybe with a little help from your friends.

What You Need: What You Are Getting Yourself Into

No surprise, you’ll need the actual grapes, and way to get them to your home. You’ll need a way to have them crushed, so that the skins are in contact with the juice of the grapes. You might need to adjust the amount of sugar in the must (the term for the juice and skins) and to correct any acidity problems. You don’t have to correct these levels if you believe in non-intervention. That is the philosophy of the “natural wine” movement. This article will assume some intervention.

The process of fermenting and adjusting the must is similar to what you might have done for correcting raw juice. But you may need a larger fermenter due to the increased volume of the must.

The final hurdle is getting the grape skins out of the juice at the end of fermentation. The wine is cleared, stabilized with metabisulfite and stored before bottling. Bottling is then the same as with a kit or juice.

Consider seeking out a producer that will crush the grapes for you as part of the purchase. Many do. That cuts out a lot of work. Or joining a wine club, which also has great advantages, such as the members who will happily share great advice and may have all the equipment you need. Fellow winemakers are usually very happy to help you out. For many of these members winemaking is a family project and a community party. The more the merrier! Ask if you can join in. The club itself may loan measuring equipment, such as PH meters and also physical equipment such as wine presses. Perhaps I am biased, but I find winemakers, professional and amateur, are convivial people and worth seeking out.

The Crush

Crushing and de-stemming grapes breaks the grape berry skin by gently pressing the berry. The de-stemmer removes the stems from the berry cluster. This process is usually done by a machine that does both at once. What remains is the crushed grape berries and the berry juice which pours into a bucket or container. You’ll need an open-mouthed container at least a couple of gallons larger than the total gallons of finished wine. For red wine, consider that 13 Lbs. of grapes will give you a final gallon. It takes 15 Lbs. of white grapes to get a gallon, as much juice remains in the discarded skins. For transporting the grape must, it is advisable to have a lid on the container. Consider using a reused juice bucket(s).

If you can’t find a producer who will crush and destem your grapes, and you can’t beg or borrow the use of such a machine, then there are still ways to accomplish your purpose. I recall meeting a young couple who were starting a winery. They had their license to make and sell wine, but not all the equipment they needed. They told me that they used multiple buckets and a big potato masher to crush their grapes. They picked out the stems as they pressed. They made do with what they had.

Some methods of fermentation use whole clusters, making the wine softer and silkier. This method would be an antique version of that popular method. Very trendy!

Adjusting the Must

Grapes make sugar and store it in the fruit, the grape itself. They also make acids, which the plant uses as the season continues. The major acid is tartaric. A second acid is malic. As grapes ripen, the acids are removed by the plant, but not totally. Sugars also build up. Grape growers are looking for the perfect time to harvest their crop, when the sugar-to-acid ratio is best for that varietal. But, it’s nature that calls the shots. As the grapes you purchase are what nature gives, the winemaker needs to examine the must and determine what amount of sugar (potential alcohol) and acid (balanced for flavor) they want in the wine.

The alcohol, along with any residual sugar, provides interest and fullness in the mouth as do the natural flavors of the wine. Too much alcohol and the wine is “hot.” There is an unpleasant mouthfeel and slight burning at the back of the throat. Too little alcohol and the wine seems hollow and becomes more susceptible to unwanted spoilage microbes.

Acid provides a refreshing quality to the wine. In whites, it is the foundation of the flavor. Too much is unpleasant. Too little and the wine is flabby and uninteresting. In red wine, the acid can react in your mouth with the tannins making the wines bitter. So both acid and sugar should be balanced in both red and white wines.

Often a grape grower catering to the amateur maker will post the sugar levels and often give an idea of the acidity. If not ask! For the grower, it’s pretty easy to test and they know those numbers as part of deciding when to harvest.

To measure sugar, two tools are used: a hydrometer and a refractometer. Both are relatively inexpensive, but a hydrometer is much cheaper. A refractometer looks like a small telescope. It uses a drop or two of juice and the amount of sugar (brix) shows on a scale when held up to the light. A hydrometer is more accurate, cheaper and shows potential alcohol and sugar levels in two scales, one of which is brix. It can also be used to test if fermentation is finished. Hydrometers can be had for about $20, including the test tube they float in. I recommend a hydrometer as your next step piece of equipment. A refractometer can range in price from $60 to $100.

Warm climates, like California, may produce grapes that have high sugars. Cool climate regions like New York can struggle to produce the appropriate sugar levels. If you find the sugars too low, add sugar. If they are too high add acidified water. For the amount needed a good reference is winebusiness.com. That site has free tables that calculate what you need to add to chaptalize or, in contrast, dilute the sugar.

Cool and warm climates switch problems when it comes to acid. Cool climate regions have a surfeit of acid, while warm climate regions struggle to hold on to the appropriate levels of acid. Sometimes, in both, the grapes are perfectly balanced. But that is rare. So, if your grapes come from a warm climate, it’s likely that some tartaric acid addition will be necessary. If your grapes come from the Mid-West or North East, then the acid might be a bit high, especially for red wines. To reduce acid, potassium carbonate can be used. Whether high or low, adjusting acid should be done with a solid idea of what the acid level is.

Sugar, in the unfermented must, will mask levels of acidity. Sugar is often used post-fermentation to balance out an acidic wine. This is why Riesling often has a touch of sugar in the wine. So just tasting the pre-fermentation must will not give you a proper understanding of the strength of the acids. Though large acid adjustments are usually done pre-fermentation, acids can be adjusted post fermentation with potassium carbonate (though not calcium carbonate). There will not be residual sugar in the wine, hopefully, and you can do bench trials with addition or subtraction of acid until you find your perfect balance. Again, winebusiness.com will be helpful to proper calculation.

But there is an easier way to approach this tricky issue. It is relatively easy and cheap. It’s called a titratable acid test kit. It will give you a general idea of the acids in your must. You can test for the titratable acid (TA) without needing a PH meter. Though a PH meter is a very nice addition to your winemaking equipment, especially when it comes time to stabilize your wine following fermentation, you can get by without one. A test kit for acid may start at about $15.

Primary Fermentation

Once you feel the acids and sugars are in balance, then you may add yeast to the must, just as you have with juice or a kit wine. A kit wine chooses a yeast strain for you, usually a powerful fermenting strain. But now, you can do some research to find a yeast that has qualities you find interesting, such as producing good aromas or enhancing the fruit qualities in the varietal. But do read about the nutrition requirements of your chosen strain. Some require a large amount of nutrient and may produce off odors if the must is low in nitrogen and other nutrients. If unsure, I recommend you use EC-1118 witch is a “beast” of a fermenter and has relatively low nutrient requirements. Though you should add nutrients.

Adding nutrients is an easy process. The first addition comes when re-hydrating the freeze-dried yeast. A common re-hydrant agent is called Go-Ferm, though there are many brands on the market. This protects the yeast during its rebirth. The second addition of nutrient, especially including nitrogen, is directly to the must. I like to use a complete nutrient like Fermaid K, or Fermaid O (organic) which is designed to prove this needed source of food for the yeast. Some winemakers, professional and amateur alike, use DAP. This product is pure nitrogen and can be tricky to use. Too much nitrogen can over-stimulate the yeast.

Standard advice is to wait until the yeast has consumed 1/3^rd of the sugar to add nutrients. But this assumes there is enough natural nitrogen in the must to start the process. Professional wineries can easily test for nitrogen in the must. I can’t. So, I like to divide my additions into two, a small amount added at the time of inoculation and then the balance after the sugar is depleted by 1/3^rd.  I hedge my bets, and guarantee sufficient nitrogen to start a good clean fermentation is in the must by adding some.

If you are unsure of the status of your sugar, thus unsure of when to add nutrient, wait two days after the start of a full bubbling fermentation to add your full amount of nutrient. But smell the must often and if things smell a bit off, add nutrient immediately.

At this point, if you are making a white wine and the skins are still with the juice, remove the skins unless you want an orange wine. Red wine needs those skins throughout the fermentation. In both cases stir the juice/must often and in red wine punch down the skins into the juice to help extract the color, flavors and aromas you want in a red wine.

I ferment both white and red wine in an open container to keep oxygen mixed in the juice/must and to help develop clean aromas. But, oxygen is a frenemy. When fermentation is completed, oxygen will cause the wine to spoil and the wine will need a stabilizing protectant called sulfite.

Final Press

Fermentation will take a couple of weeks. During that time the skins are still releasing flavor and color. So, there should be no rush to remove them. But at the end of fermentation the skins need to be separated from the wine and the wine allowed to settle and clarify. A wine press is used to remove the skins and press out the remaining juice in the skins. (A wine press is also used to separate and remove the juice form white wine grapes before fermentation).

If you can’t find a friend to help you out with this job, do not fret. There is a way to do this without losing much wine. You will need a colander with lots of holes. And, if it’s something you have, a chinois, which is a funny-looking food press, can also be helpful. Source a colander that will fit the top of a food grade bucket. Strain the wine through the colander pressing the skins with a potato masher. That will press out much of the trapped wine. If your pantry has a chinois, you can do a final squeeze of the skins with that.

This process adds a lot of air to the wine, so try to gauge when the wine’s fermentation has a few brix to go until complete dryness so that the added oxygen will help the yeast finish fermenting the last of the must’s sugar. Like people climbing a mountain, that last third is the hardest.

Your hydrometer’s readings will not be accurate because the alcohol now present in the wine will skew the measurement gauged for sugar in solution. But the hydrometer is still useful. When the bubbling has subsided and the gross lees (mostly yeast) are settled in the carboy, check for the completeness of the fermentation. If the measuring bulb sinks to the bottom of the measuring tube, without floating, then fermentation is complete. It’s time to rack the wine off the lees and also to protect and stabilize the new wine.

Stabilizing

Along with nitrogen, oxygen is a friend of fermenting yeast. So during fermentation, yeast should be allowed as much oxygen as possible. When fermentation is complete and the yeast has done its job, then oxygen becomes an unwanted companion in the wine. To keep wine stable, all air (containing oxygen) needs to be kept away from the wine. All wine containers should have a closure (an airlock) and the wine should be at the top of the container. This keeps air out. Also, sulfite (SO2) is added.

Sulfite is used to stabilize the wine by chemically binding to oxygen, denying any spoilage microbes the oxygen they need to grow. Sulfite is expressed in parts per million (PPM). So, it is powerful stuff. But it can be readily purchased in any wine or beer making store. It will have directions on how to add the white powder. But how much?

If you have access to a PH meter you can get a better idea of how much you need. PH and sulfite are intertwined. The lower the PH, the less needed. The higher the PH and the amount becomes exponentially larger. There are charts that are found in many websites, including Wine Maker Magazine. The standard that works for me is to use the last two numbers of the PH as the amount needed at a minimum. For instance if a white wine has a PH of 3.20, I would use 20 PPM for a minimum. If a red wine has a PH of 3.60, I would use 60 PPM. It’s a good ballpark calculation.

Keep in mind that some of the sulfite will bind with the free oxygen in the wine, but some might bind with other compounds in the wine. And this will happen more and more over time and even later in the corked wine bottle. So there is a difference between “free” and “bound” sulfite. Bound sulfite does not have a protective effect. Reapplication may be necessary.

So, what do you do if you have no access to a PH meter? I don’t recommend this, but you can wing it. If you have a very acidic wine, almost always white, then 40 to 60 PPM may work. Cool climate reds tend to be above 3.50, so 80 PPM may work for you. Warm climate reds (think California) are usually much higher in PH than cool climate reds and 100 PPM is safer.  

Another possibility is to hit all your finished white wine with 60 PPM and all reds at 100 PPM or all at 100 PPM. 100 PPM is well below recommended total amounts, and will likely cover most of the PH ranges in wine. That amount will sink down over time and it’s unlikely to be noticed by the time the wine is bottled and aged. For warm climate reds you should consider adding about 20 PPM more at bottling due to the addition of oxygen. 

Keep track of any additions of sulfite as you should never exceed 300 PPM total addition! But this is an absolute maximum and the goal to use only what you need. Also be careful to properly measure your sulfite additions. As a general guide, for small batches, one normally uses eighths, quarters, half teaspoons, and maybe a full teaspoon of potassium sulfite, depending on the amount of finished wine and whether you are working with warm climate reds. Sulfur should not hit your nose when drinking the wine. If it does, you may have made an addition error.

Another stabilizing agent is potassium sorbate, or just sorbate for short. It’s often included in kit wines as a final addition. It prevents re-fermentation in the bottle by residual yeast where there may be some unfermented sugar in the wine. Residual sugar may be intentionally left in the wine, like a touch of sugar in an acidic wine such as Riesling. Or the sugar may be there because the fermentation was not complete. Sometimes fermentations just plain stop before all the sugar is transformed (known as a stuck fermentation) but come alive when the weather warms up. It’s a real disappointment to discover that your supposedly completed wine is now pushing corks out of the bottle or the bottle is exploding!

Don’t ignore the directions on the product. You must have at least 50 PPM of sulfite in the wine and must use the recommended amount of sorbate. The sulfite prevents unwanted reactions with certain bacteria. 

Sorbate is not a required but sometimes helpful addition to finished wine. It does have some downsides. Some people can’t taste the sorbate, but those who do may find it adds a pineapple or tutti-frutti aspect to the wine. Also, you must be careful to not allow a second fermentation with malic acid bacteria (known as a malolactic fermentation) as this is the bacteria that will produce a geranium odor in the presence of sorbate. Thus keep your sulfite level high to kill this bacteria.

Congratulations! Having dealt with crushing the grapes, fermenting the must without a supplied schedule, and without having pre-made packets to add, then removing the skins and stabilizing the wine, you are now in the same game with your favorite professional winemaker. The next level is to hone your craft and bring it up to a more professional level. Join that wine club! Your comrades will be happy to discuss the merits of your wine and share of their winemaking techniques (and equipment) with you. Consider entering wine judging competitions. Judges who evaluate your wine are usually rigorously trained and will often add comments to their scoring sheets that can help you to make better wine. The scoring sheets are almost always shared with the maker.

For those who seek deeper technical assistance in winemaking, I recommend an easy to use guide written by a professional winemaker and a trained chemist: Techniques in Home Winemaking, by Daniel Pambianchi. His book has been of great help in my winemaking endeavors. Let’s keep movin’!