Which wines should get malolactic fermentation?
Generally, only wines made from grapes get malolactic treatment. There are two reasons for this, the first being that the bacteria needs a small amount of grape pulp and solids to get a foothold in the wine. Second, it is only really the top quality wines that merit malolactic treatment, and these are most often sold in the form of grapes.
Wines made from concentrate are generally unsuitable for malolactic treatment. Not only are the acidity levels usually balanced toward the low side for early drinking, the levels of solids in concentrate are virtually nil. In addition, some concentrates may have small amounts of sorbate in them, causing geraniol problems.

The treatment criteria for wines are as follows:
The wine should be one where complexity is desired over fruitiness. ML tends to emphasize fermentation aromas and flavours and reduce the fresh fruity flavours of a wine. If this doesn’t suit your palate, you should reconsider treatment.
The wine must have an alcohol level below 14%. Malolactic bacteria are not especially alcohol tolerant, and a wine with a higher alcohol content will not support it.
The wine must have a pH of 3.3 or greater. If you don’t know what the pH is, it will be necessary to have it tested before attempting malolactic inoculation.
The wine must have some grape pulp or yeast sediment to promote the growth of the bacteria. If it is clear, MLF will be very difficult to start.

What form does the malolactic bacteria come in?
There are two main types of malolactic culture available, refrigerated liquid culture, and freeze dried powder. They are both perfectly good choices for inoculating your grapes. They both have to be kept refrigerated at all times.
They both come with instructions for use, which, while fine for inoculation in a laboratory setting, are somewhat confusing for the home user.

What are some of the dangers of malolactic fermentation?
In addition to transforming malic acid into lactic, leuconostoc oenos also transforms citric acid into acetic acid, which is the acid that gives vinegar it’s distinctive flavour. This usually isn’t a problem, unless the must has been treated with citric acid.
Also, because it reduces fruity flavours, there are few white wines that will benefit from ML, and some reds are best left fruity as well.

Because ML fermentation can cause the pH of the wine to rise, it may make it more susceptible to other forms of bacterial infection. You may need to adjust sulphite levels to compensate.

Partial ML, or ongoing malolactic fermentation in a wine that is to be bottled can cause the wine to carbonate (become fizzy), break the bottle with CO2 pressure, push out the cork, and spoil the flavour. You must be certain that ML is complete and/or arrested before bottling (see below).

How do I go about starting a malolactic fermentation?
Assuming you have purchased good quality grapes, you have tested the acid and pH, and are confident that going through ML will produce a better wine for you, the first step is to obtain a malolactic bacterial culture. These are sold by Wine Cave, and are labeled as ‘Leuconostoc Oenos Bacteria’.
If you are only inoculating 23 litres of wine, you don’t have to make a starter culture with either the freeze dried or liquid cultures. With the liquid culture package, when the grapes are almost finished fermentation (below) simply match the temperature of the package with the temperature of the grapes (it should be 20-25°Celsius) and add it. Within two to three weeks the ML will be well under way, and should be complete within two months.

With the freeze-dried culture it is necessary to make a sterile suspension and rehydrate the bacteria. For two grams of culture, prepare 25 ml of distilled water at 25-30° Celsius in a sanitised cup and sprinkle the culture on top. After 15 minutes, stir with a sanitised spoon and add to your fermenting must. Again it is important that the wort be below 5°Brix, so as not to slow the ML.

If you are inoculating more than 23 litres, you should purchase the culture about two weeks before your wine is nearly fermented dry, to allow time to make a starter culture. Judging the point when your wine will be two weeks away from dryness may seem difficult on first blush, but a good rule of thumb would be to purchase the culture the week before you receive your grapes.

A culture from liquid is prepared thus: obtain 2½ litres of fresh grape juice. Choose a grape juice with less than 15 PPM of SO2, and with less than 20° Brix of sugar content. If you can’t find an available juice with these characteristics, it is possible to change the pH and sugar content of a less suitable juice by either diluting with water or adding a pH adjuster. Ask your retailer for advice. Make sure you use only grape juice: apple juice or grape concentrate is not suitable.

Add about 1 gram of yeast energizer to the juice. This will help speed cell growth. Ensure the juice is between 20-25°C and inoculate with a package of malolactic friendly yeast (Epernay is ideal) and allow to sit for 2 days, and inoculate with liquid malolactic culture and maintain a temperature of 20-25°C.

After 12 days the culture will be ready. 2½ litres is sufficient for 120 litres of wine. If you have more than 120 litres, you can culture up the amount you need by simply adding your starter culture to larger amounts of suitable juice. You will need approximately ½ litre for every 23 litres of wine.

When is malolactic fermentation finished?
If the wine is kept at relatively warm temperatures (above 20°C) the fermentation will be complete within two months. The only way to monitor this is through the use of a malolactic chromatography test kit, if you wish to know that your malolactic fermentation is complete, an accurate test is the only way to find out.

Once you are satisfied that your ML is finished, you can stabilize your wine by adding sulphites to the level of approximately 50 PPM. This will prevent the re-growth of any leuconostoc bacteria, and will prevent oxidation. It is a good idea to test the pH and acidity of your wine at this point as well. Because ML can cause the pH to rise, you may need to adjust it. Space doesn’t permit a full discussion of pH and wine quality, but several winemaking books contain good sections on pH.

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You may be asking yourself, “why do I need all these ingredients?” That’s a good question, and here’s the answer. Each one of these ingredients plays a distinctly different and vital role in both the wine making process and the resulting flavor of the finished wine. Here is a brief description of what these ingredients do.

Yeast Nutrient: This is not yeast, but rather, energy for the yeast. It insures that your yeast will ferment and make alcohol sufficiently.

Yeast Energizer: Used in place of Yeast Nutrient when fermenting fruits that severely lack the nutrients yeast expects to do its job. It is a more extensive array of nutrients than Yeast Nutrient.

Pectic Enzyme: This is added to help break down the fruit so that you can extract more flavor and body from the fruit. It also helps to insure that your wine will clear up successfully.

Acid Blend: This is used to control the sharpness of the wine. Many wines will not have enough acid on their own once the required water is added. This can leave the wine tasting flat.

Wine Tannin: This is the zest of the fruit. It is added to increase the character of the wine and to help aid in its clarification. It also helps the wine to take better advantage of aging while in storage.

Wine Yeast: This is what actually does all the work. It turns all the sugars in the mix into precious alcohol. NOT BAKERS YEAST!

WHY NOT NOT BAKERS YEAST?
The thing with bakers yeast (which is closely related to vintners & brewers yeast) is that it will have a low attenuation (low alcohol producing ability) leaving your wine somewhat short of your goal. It will also leave the wine cloudy. Finally when it goes through autolysis (a horrible yeast death that burst the yeast open when it dies-LOL) it releases bitter vitamins (B) into the wine. The dead yeast must be filtered as it is now food for spoilage organisms.
In contrast a vintners (wine) yeast is much better suited to producing the alcohol and flavors that have become appreciated in wine.

Campden Tablets: These tablets are added before fermentation and again before bottling. They insure that your wine does not spoil and remains fresh tasting up to the point of consumption. Getting these ingredients in the right balance along with the fruit, sugar and water will allow you to produce wines of exceptional character and flavor.

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1. Pour milk into the pre-sterilized 5 quart stainless steel pot. Warm to 65 F with stirring.
2. Meanwhile, dissolve 1/4 tablet rennet in 1/4 cup water.
3. When the milk reaches 65 F, remove from heat, add buttermilk, whisk to mix thoroughly.
4. Stir the dissolved rennet into the 65 F inoculated milk, blend thoroughly.
5. Cover and let sit overnight undisturbed at room temperature (65-70F, 20C).
6. The next morning, a clean break should have formed (see recipe for basic cheese for the test). If the coagulated milk is not firm enough, let it sit until is does, as long as another 12 hours.
7. When a clean break is achieved, cut the curd into 1/2 inch cubes (see recipe for basic cheese for technique). Some recipes call for stirring the soft curd with a whisk. This will work, but will make the separation of curds and whey more difficult.
8. Ladle the curds and whey into a clean sterile handkerchief supported in a large strainer, placed over a one gallon bowl. Allow the whey to drain through. If the cloth becomes clogged, lift the cloth back and forth or scrape the curd away from the cloth. Save the whey for ricotta if you wish (see recipe).
9. When most of the whey has drained through, pick up the four corners of the cloth and suspend the curd in a cool place to drain overnight (from a shelf of the refrigerator if you have room).
10. The next day, remove the cheese and mix in1- 3 teaspoons of salt, according to taste. It may be eaten immediately. Store covered in the refrigerator until use.
11. You may pack the cheese into a mold of your choice (a squat tin can with the ends removed for instance).

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1. Warm the milk in the sterilized pot to 86°F (30°C). Do not let it burn on the bottom. Remove from heat.
2. Mix yogurt with an equal part milk to blend, then stir into the warmed milk to mix thoroughly.
3. Cover and let inoculated milk sit for one hour at room temperature. Meanwhile, dissolve 1/2 Junket Rennet tablet in 1/4 cup of cool water.
4. After the inoculated milk has set for one hour, stir in the dissolved rennet to mix well.
5. Cover and let the inoculated, renneted milk sit overnight at room temperature.
6. The next morning, the milk should have gelled to produce a clean break (as in the basic cheese recipe). Some of the whey will have separated. Cut curd as per basic cheese (see recipe). The curds should be about 1/2 inch in diameter.
7. With very clean hand and arm, reach to the bottom of the pot and gently lift the curds to stir. Cut large pieces which appear with a table knife so that they are 1/2 inch pieces. Continue gentle stirring for 10-15 minutes until curd is somewhat contracted.
8. Decant off the whey through the handkerchief supported by the strainer, then pour curds into handkerchief. Let the curds drain until no more whey drains out (about 2-4 hours). The whey may be saved for ricotta (see recipe).
9. Transfer the drained curds into a bowl, break into small pieces and mix in 1/2 tsp salt.
10. Prepare the cheese mold by lining the tin can (with ends cut out) with a handkerchief. Place the curds into mold, fold over ends of the cloth, place one of the cut ends on top, and place a heavy weight on top to press the curds. Let sit overnight to drain.
11. Prepare pickling brine (12.5% salt): 20 oz of water plus 5 Tbl salt. Stir to dissolve.
12. Remove the cheese from the press and cut into 1.5 inch pieces. Place into a wide-mouth quart jar. Pour brine over to cover. Let pickle for 1-2 days in the refrigerator. The cheese pieces may then be removed from the brine and stored in an air tight container in the refrigerator. Rinse before use to remove excess salt.

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