Expert Advice: Wine Additives

People are freaked out by chemicals. We picture slimey billionaires, scheming behind a desk, counting their vast sums of money that have been made by poisoning innocent people with their chemical laden products. I understand your concern. There are enough class action lawsuits pending out there to make anyone leary of the word “chemical”.

However, not all chemicals are necessarily bad, just as not everything labeled “all natural” is good - arsenic comes to mind - it’s naturally occurring in the world, but would you eat it?

There are a few chemicals, or additives, that are actually helpful, if not essential to wine making. However, I still get a lot of reactions of shock and horror when I advise a novice wine maker to add, say, potassium metabisulphite to their wine. I mean, it doesn’t sound like it would taste good. It doesn’t even sound safe. It sounds like something that might be found in a cleaning product you keep under your kitchen sink.

So here I’ll break down some of the common additives (let’s use that word, it’s less scary) in home winemaking. I’ll let you know what they are made of, what they are used for, and in what quantities. Then, you can make your own informed decision. Ready?

Acid Blend

What is it: a blend of three different acids commonly used in winemaking: 25% Tartaric Acid, 25% Malic Acid, and 50% Citric Acid. Why should I put it in my wine?  It improves the flavor of your wine, giving it a boost of the acids already found in the fruit you are fermenting. Acid levels can be off depending on the ripeness of the fruit, whether it was fresh or frozen, when it was pressed, etc. Acids affect how “sharply” you can taste the flavors of the fruit used in winemaking, so it is very important to make sure your acid levels are balanced. How much should I use? This is a tough question, and will vary depending on the type of fruit you are using, but a general rule is about 1 teaspoon per gallon of must.

Tartaric Acid

What is it? A white, crystalline, organic acid that occurs naturally in many plants, most notably in grapes. Its salt, potassium bitartrate, commonly known as cream of tartar, develops naturally in the process of winemaking. It is commonly mixed with sodium bicarbonate and is sold as baking powder used as a leavening agent in food preparation. Why should I put it in my wine? The acid itself is added to foods and beverages as an antioxidant and to impart its distinctive sour taste. How much should I use? This is a tough question, and will vary depending on the type of fruit you are using, but a general rule is about 1 teaspoon per gallon of must.

Malic Acid

What is it? An organic compound with the molecular formula C4H6O5. It is a dicarboxylic acid that is made by all living organisms, and it contributes to the pleasantly sour taste of fruits, and is used as a food additive. Why should I put it in my wine? Another type of acid that contributes to the sourness of most fruits. How much should I use? This is a tough question, and will vary depending on the type of fruit you are using, but a general rule is about 1 teaspoon per gallon of must.

Citric Acid

What is it? A weak organic tricarboxylic acid having the chemical formula C6H8O7. It occurs naturally in citrus fruits. More than a million tons of citric acid are manufactured every year. It is used widely as an acidifier, as a flavoring and chelating agent Why should I put it in my wine? Citric acid enhances the fruitiness and liveliness of wines. Wine that is short on citric acid tastes “flat” with little mouthfeel and very little complexity. How much should I use? This is a tough question, and will vary depending on the type of fruit you are using, but a general rule is about 1 teaspoon per gallon of must.

Tannin

What is it? A tannin (or tannoid) is an astringent, polyphenolic biomolecule that binds to and precipitates proteins and various other organic compounds including amino acids and alkaloids. The astringency from the tannins is what causes the dry and puckery feeling in the mouth. Why should I put it in my wine? Astringency by itself isn’t always a great thing, but in wine, it’s crucial. The astringency adds mouthfeel and flavor to the wine. The reason extra tannin is needed is because tannins are found mostly in the skins and stems of the fruit, which are often discarded and not included in the fermentation process. How much should I use? Recommended usage varies according to the type of grape or fruit, but rule of thumb is 1/2 teaspoon per gallon of must.

Potassium Sorbate

What is it? is the potassium salt of sorbic acid. It is a white salt that is very soluble in water. It is primarily used as a food preservative. Why should I put it in my wine? It is used in wine to inhibit bacteria, mold, and yeast growth, which is essential to the aging process. It also inhibits refermentation from taking place, so when you do finally get those wine bottles on the racks, you don’t have corks blasting across the room. How much should I use? Use ½ teaspoon per gallon of wine.

Potassium Metabisulfite

What is it? A white crystalline powder (or Campden Tablet) with a pungent sulfur odour. The main use for the chemical is as an antioxidant or chemical sterilant. It is very similar to sodium metabisulfite, with which it is sometimes used interchangeably. Potassium metabisulfite is generally preferred out of the two as it does not contribute sodium to the diet. Why should I put it in my wine? To inhibit bacterial growth and retard oxidation, both of which are integral to the aging process. How much should I use? Use 1 teaspoon per 6 gallons of wine, or 1 campden tablet per gallon.

Yeast Nutrient

What is it? A delightful mixture of amino acids, vitamins, and minerals, (biotin, pantothenic acid, calcium, magnesium, potassium, just to name a few). Why should I put it in my wine? This mixture of good stuff is exactly what yeast need to be happy and healthy. It will ensure that your fermentation gets off to a good start and finishes all the way through. How much should I use? Use 1 teaspoon per gallon of must. Wait 24 hours before adding yeast to ensure the healthiest environment possible for fermentation.

Yeast Energizer

What is it? A blend of magnesium sulfate (commonly known as Epsom salt, used to improve crops, relieve aches and pains, etc,), yeast hulls, and vitamin B complex. Why should I put it in my wine? Use it only if you have a slow or stuck fermentation. It gives your yeast a shot of energy. Yeast hulls are basically the dead husks of yeast cells that the new yeast cells “cannibalize” for a boost of energy. How much should I use? Use ¼ teaspoon per gallon of wine.

Of course, humans have been making alcohol for thousands of years, and nothing is required for fermentation but yeast and sugar. Still, don’t be afraid of chemicals. Most of them are byproducts of naturally occurring processes, and they will help make your wine taste as delicious as those store bought bottles. Cheers!