Additives in Winemaking

August 19, 2021

Regular readers of my blog will know I'm not a great fan of some additives in wine making. For example, I would prefer to leave a demijohn of homemade country wine for 6 months to clear naturally than to add finings, an additive that speeds up the clearing process. The purpose of this list of Additives in Winemaking is to explain some of the options available. Then you can decide whether or not you wish to use them, or find a 'natural' alternative where one exists.

Additives in Winemaking can improve your homemade wine

One of the reasons some people start making wine, me included, is because we want to know what's in it. And we want to keep things as 'natural' as possible. However we need to keep in mind that our lives are full of chemicals. They are not always the enemy, by any means. Without cleaning/sterilising chemicals, for example, we could end up with unwanted bacteria in our wine which would spoil the whole brew.

Blackcurrant wine in a bucket

Additives tend to be included in most wine recipes. Some are there to fix a problem, some to stop a problem happening in the first place. Yeast is an obvious one. Finings are another. Finings are an efficient way to clear your wine, and there's every chance that your wine cleared with finings will end up crystal clear. Whereas mine, which has been left for 12 months or more to clear without finings, may never end up as clear as yours. I still prefer not to use finings when I can use time to clear my wine. But the reality is: if I don't add pectin enzyme early on in the (for example) parsnip winemaking process, my parsnip wine may never clear.

Meanwhile acids can serve a number of purposes in home brewing. They can inhibit unwanted bacteria, help fermentation, improve taste and speed up and/or improve maturation. If there are not enough natural acids in your fruit, you can add acid from a tub.

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A word about Sulphites

We are often asked about sulphites, specifically whether it is ok to leave them out of homemade wine. Sulphites are widely used in a lot of the products we eat and drink, from preserves to fruit squash. If you check your kitchen cupboard labels you may spot Sulphites, Sodium Metabisulphite, Potassium Metabisulphite or Sulphur Dioxide. These are all examples of sulphites which help to preserve our food and drink.

Used widely in winemaking for all the right reasons, the most well known sulphites act as a preservative and slow down/prevent oxidisation, so your wine stays fresh for longer.

Metabisulphites are also used widely in commercial wine production, which is why wine labels usually state that the wine contains sulphites. The quantities used in home winemaking are often smaller than you find in other products in your kitchen.

Even if you don't add sulphites to your wine, no wine is entirely sulphite-free because they are naturally created by the wine making process. However if you are intolerant to them, you can choose not to add more as your winemaking skills develop. And if you are making a wine kit, you can leave out the sulphites at the end, as we usually do. You just need to be aware that your kit wine will need to be drunk fairly quickly, as it won't last as long without this widely-used preservative. And if it's a homemade wine which needs a long time to mature, like elderberry, then sulphites will be the difference between it having time to mature and going off before it gets the chance. Again, it is down to personal choice.

The most common way to buy sulphites for wine making is in the form of Campden tablets, which are covered in this list.

15 Additives in Winemaking

Acid Blend is a mixture of Citric, Malic and Tartaric Acid. A recipe may call for one or more of these acids to be added separately. But when it asks for Acid Blend, this is what the recipe is asking for. The characteristics of each of the three acids are explained below.

Bentonite is a natural clay used for clarifying and stabilising wine. Bentonite attaches to yeast and particles and falls with them to the bottom of the fermenting vessel to form a sediment. This helps to clear your wine, and is suitable for vegetarian and vegan wine making unlike other clearing products (see Finings later).

Campden Tablets. Usually made from potassium or sodium metabisulphite, Campden Tablets have a number of uses, both in the making of the wine and the sterilising of equipment. Campden Tablets can be used:

- to sterilise the 'must' (the ingredients you start with when they are mixed together). Mix the Campden Tablets into the must and then leave for 24 hours before you add your chosen yeast. This is important as Campden Tablets kill off all bacteria, including good yeast bacteria, so it can kill your yeast if you don't leave a 24 hour gap after using Campden Tablets and before adding yeast.

- to help stop fermentation. Adding Campden Tablets to your must once fermentation seems to have stopped inhibits yeast reproduction and so helps avoid exploding bottles. It also encourages the dead yeast and any pulp stuck to it to sink to the bottom, to help clear your wine. However fermentation can still restart if you only use Campden Tablets to stop it. Adding Fermentation Stopper in combination with Campden Tablets is the ideal way to stop fermentation using additives - see more about Fermentation Stopper later.

- when racking off. Some people add a Campden Tablet to their wine every time they syphon the wine off the sediment. This is to prevent the wine oxidising which can spoil the taste.

- to sterilise equipment. Campden is the only steriliser that can safely be used in the wine itself as well as for sterilising equipment. This is different to a cleaner/steriliser product like VWP, which can be used on equipment but not in the wine itself.

Calcium Sulphate aka Gypsum. Calcium Sulphate is used to improve water in home brewing by lowering its pH. Gypsum does come up occasionally in wine recipes, bu it is used more often in beer making.

Citric Acid is the main acid in winemaking fruits such as currants, elderberries and strawberries as well as citrus fruits. Citric acid is added to wine for flavour, and also helps to promote fermentation.

Fermentation Stopper aka Potassium Sorbate. Potassium Sorbate is a yeast inhibitor. It stops bacteria dividing and producing new cells, so is designed to stop fermentation before bottling. It is usually advised that you add Campden Tablets as well as Fermentation Stopper to maximise the likelihood that your fermentation has definitely stopped. As well as this,Young's advise that when using Potassium Sorbate you should use Campden Tablets at the same time to avoid a duranium (metallic) smell in your wine.

Finings. Many wine recipes include a fining/clarifying step. This involves adding a fining agent to the wine which is later filtered out. Finings gather proteins and sediment then sink to the bottom, helping the wine to clear more quickly than waiting for this to happen naturally. Finings are often animal based, which is why many commercial wines cannot be labelled as vegetarian/vegan. For example gelatine is usually derived from animal body parts, isinglass from fish bladders, and albumen is derived from egg whites. Bentonite clay is a non-animal based alternative which can also be used to clear wine.

The alternative to using any finings at all is the use of time instead. If you want to avoid adding them, then you need to be prepared to wait for your wine to clear naturally. Once you have removed the cleared wine from the sediment, another non-additive way to ensure the wine is clear is by filtering it. This is why commercial wine producers use finings, because the alternative can be a slow, labour intensive process.

Malic Acid is the main acid in apples, rhubarb and blackberries. Malic Acid helps with the fermentation and maturing of the wine.

Pectic Enzyme. When making jam, pectin in the fruit helps your jam to set which is usually what you want. When making wine, pectin creates a haze which you don't want. Pectic enzyme decomposes the pectin in your fruit or vegetables in the early stages of the wine making process, to help speed up the clearing of your wine later on.

Precipitated Chalk aka Calcium Carbonate is used to reduce the acidity in country wines, particularly when using highly acidic fruits like rhubarb, red currants and apples. Precipitated chalk is usually added at the start of the wine making process.

Sodium Metabisulphite - see Campden Tablets above.

Super Wine Yeast Compound. Another blend, this is one of our best selling wine additives. Containing Bentonite, Wine Yeast, Yeast Nutrient, Vitamins and Minerals, it is used for making high alcohol wines, and to speed up fermentation and clearing. As Super Wine Yeast Compound contains wine yeast and nutrients, no additional yeast needs to be added.

Tannin. Tannin occurs naturally in fruit skins, more so in red than white fruits. One of the main functions of tannin in wine is to give it astringency. This is especially important in red wines which need it for depth. Tannin also combines with proteins in the wine making process to help to clear it. Tannin is the reason that red wines take longer to mature, and can taste harsh if drunk too young. Wine tannin is usually made from grape skins. Prior to commercial tannin being available, wine makers used to use strong black tea to add the tannin element to their wines.

Tartaric Acid is found in grapes and fruits derived from grapes, like raisins. Tartaric Acid imparts flavour to the wine.

Yeast. There are two types of yeast available to the winemaker. One is the ambient yeast which exists naturally on the fruit. An example of this is the apples in cider making. We make cider using cider yeast, but we also make 'wild' cider by leaving the cider to ferment naturally, using the wild yeasts present in the juice. You can also make elderflower champagne using the yeasts naturally present in the flowers, in the same way.

The other type of yeast is far more commonly used and we sell it in our shop: cultured Wine Yeast. Using cultured yeast usually involves sterilising the fruit juice to kill off all the natural yeast, then replacing them with the cultured yeast from a packet.

The main reason for doing this is predictability. Naturally produced yeast is unpredictable. Even if it works really well in one batch of wine, it can be virtually impossible to produce the same results twice. Worse, if you have undesirable bacteria in your fruit or flowers that you can't see, they can spoil a batch and you may end up pouring the whole lot down the sink. That is why cultured yeasts became popular. If you always follow the same process, the yeast usually gives the same result. So if you liked it the first time, you can keep producing it again and again.

Yeast Nutrient. Yeast nutrient is often included in homemade wine recipes. It is not yeast, but rather it is food for the yeast. Yeast nutrient feeds yeast from the start, to ensure fermentation starts quickly and a vigorous fermentation is maintained.

This list contains 15 additives you will find in winemaking recipes, and there are more as well as these. As you make more homemade wine and get to know the ingredients, some additives you will choose to use, and some you may not. It is entirely personal choice.