 |
||
 |
||
Subscribe to
our |
||
 |
||
|
White Wine Making Making your own wine can be loads of fun and a very satisfying hobby, especially doing it with friends. You can make it as simple or as complex as you like. Have a read of this first and speak to us if you have any queries. This pamphlet is designed as an introduction only and as a guide.
Good wine can only be made with good grapes. The best flavour and aroma is generally considered to come from grapes from cool climate areas where the fruit undergoes a longer ripening period. Equally, grapes should be in good condition. Crushing as soon as possible after picking is the ideal and certainly avoiding any old mouldy grapes is recommended. As a general rule its best to try to use wine grapes to make wine and eat table grapes. So most of us are looking for Chardonnay, Reisling, Semillon, Sauvignon Blanc and a small range of other grapes that experience has taught make the best wine. If you have problems obtaining good quality grapes, please speak to us at the shop early in the year.
Before doing anything, sanitise all equipment that will come into contact with the grapes, eg. drums, crushers, spoons etc. Use Sodium Metabisulphite, Brewchlor or other sanitizers at the rate recommended on the package and rinse with plenty of water.
When making white wine it is crucial to avoid oxidation. Read the section on oxidation at the end of this leaflet. Minimize splashing and contact with air apart from during the early stages of fermentation. If possible use carbon dioxide over the wine. Dry ice can be useful and can be purchased from gas suppliers. Crush and destem all the grapes using a suitable crusher and destemmer.
These items are all available from our stores for a reasonable
daily rental fee, or for purchase. It is best to crush grapes when cool (5-15 degrees). Test the juice with a hydrometer. It should read in the range 11 to 13 Baume or Specific Gravity of 1085 to 1100.
Sulphur dioxide acts in winemaking to prevent growth of bacteria
and mould and to inhibit oxidation. One level teaspoon of potassium metabisulphite is equal to approximately 5 grams. If the grapes are in good condition and recently picked, add 1.2 grams per 10 kilograms of grapes. BEFORE PRESSING Crushed grapes may be pressed immediately or can be left for up to 24 hours. Some skin contact may be of benefit for flavour extraction with good quality grapes, however it is important to keep the temperature low to avoid extraction of astringent phenolics and tannins. Adding a pectic enzyme at this stage will assist with clarity and yield. See notes at the end of this leaflet. PRESSING The next step is to press the grapes to separate all of the skins from the juice. Try to minimize splashing during this process. Pour or scoop the wine and skins into the press once it is assembled. Be sure to have some method of collecting the wine as the juice will start to flow out of the press straight away. Several 10 litre buckets are ideal. Then transfer as soon as possible into the containers in which the juice will be settled. Once the press is filled with the grape skins you can start to press the wine. This is a fairly straightforward procedure. The only important thing to say about this is not to over-press the skins. This will achieve very little in the way of additional juice, but will extract excessive amounts of harsh tannins from the grapes. The best quality wine is made from the free-flowing juice that is the first to flow from the press.
Allow the juice to settle under refrigeration for 12 to 48 hours. Ensure that there is minimal oxygen contact during this period. At conclusion, rack juice off sediment into the container it will be fermented in (demijohns are excellent) and allow to warm slowly to about 15 degrees. We use and recommend the use of suitable size glass demijohns, stainless steel kegs with the wine held under carbon dioxide or variable capacity tanks. Demijohns range in size from 5 to 54, litres with several sizes in between. ACID ADDITION The next step is to decide whether or not the must requires any tartaric acid added to it. This food acid is added to the wine to ensure the right balance of acidity to the finished wine. Without this acid the wine will taste unbalanced and will not last any length of time. While it is possible to adjust pH in the finished wine it is highly desirable to at least get it near the recommended range prior to the commencement of fermentation. Generally, grapes picked from warmer areas will require the addition of a reasonable amount of acid due to the fruit being over-ripe (too much sugar). This is a good reason for spending a little more money on the fruit. Fruit from cooler areas will be more expensive, but it will always produce a superior finished wine. There is no strict rule for the addition of tartaric acid to juice as a number of factors can have a bearing on the quantity required. If you have a Ph meter or papers the method to follow is to test the Ph, if it is above the recommended level add a measured quantity to a sample of the juice, eg. 5 litres, test again and add more if required. At Grain and Grape, we can test the pH of your wine for a small fee. Take a sample of the juice and measure its acidity (pH) with suitable pH papers or a pH meter. The pH should be in the range 3.1 to 3.4. If the pH is higher than this it will require the addition of tartaric acid. If the pH is in the higher range, around or above 4.0 pH add 3
grams per litre.
The next step is to add the yeast to ferment the grape juice. It is possible to ferment wine without the addition of a cultured wine yeast, but this is the single biggest cause of failure in wine making. We use and recommend Lalvin EC1118, M1and M2 wine yeast and the excellent range of Wyeast liquid yeast cultures. Dissolve 5 grams of dry yeast in 50 ml of warm water (40 degrees) for each 25 litres of must. Let stand 15 minutes without stirring, then stir well to suspend all the yeast. Add to the must. In addition to yeast you will need to add a suitable yeast nutrient. We use and recommend D.A.P. (Diammonium Phosphate). This is a very simple nutrient which will guarantee a strong fermentation and reduce the risk of the production of hydrogen sulphide (rotten egg) gas. Use at the rate 1 gram per 5 litres of must. Add at the time of pitching yeast. PRIMARY FERMENTATION The wine will start to ferment in a container which should be only about 80% full. Put the balance of the juice into the refrigerator. Oak chips may be added at this stage. Follow the instructions in the notes below if you want to use them. When fermentation slows, top up your container with the wine stored in the refrigerator and allow to ferment to completion. Fermentation is complete when a hydrometer reading of below -1 Baume or 993 Specific Gravity, is achieved. At completion of fermentation, the use of bentonite is very useful to aid the clearing of the wine. Use 0.4 grams per litre. Mix bentonite well with 50 ml of water 12 hours before use. Add to the wine and stir gently to distribute evenly. RACKING AND STORAGE Leave the wine in the full container for one to two weeks after fermentation has completed. Racking, or transferring the wine, is the next step towards the finished wine. This is simply the procedure of moving the wine from one container to another, to allow the yeast to settle out, so the finished wine will be clear and sediment free. Try to transfer the wine from container to demijohn as gently as possible to avoid contact with too much air. Once in the demijohn fit a rubber bung and airlock to make sure the wine is protected while the fermentation is completed. Syphon, or drain the wine, via a syphon hose from the first demijohn to another one of exactly the same size. Do this as gently as possible, again to avoid oxidation. Stainless steel kegs used in conjunction with carbon dioxide are another excellent storage vessel, as are stainless steel variable capacity tanks. New oak barrels are also excellent storage vessels, although once again, they should be kept full at all times. Old oak barrels, especially ones which were originally used for whiskey or bourbon, are not recommended. They don’t impart good flavours and as the years go by, generally harbour bacteria which can impart very bad flavours. Wineries generally only use their barrels (and these are new ones) for 3 to 4 years and keep them full at all times. Add 1 gram of potassium metabisulphite for each 10 litres of wine just prior to racking as an anti-oxidant.
Once the wine has sat for a further 6 – 8 weeks, it is time to bottle it. Again add 1 gram of potassium metabisulphite for each 10 litres of wine just prior to racking as an anti-oxidant. Simply fill into cleaned and sterilised bottles of your choice, taking care to minimize splashing and leaving any sediment in the original container.
Now comes the hard part, waiting for it to mature. This will usually take between 6 - 9 months as a minimum, and is at its best from 18 to 4 years.
Oak is an important contributor to the flavour and aroma of some commercial wines, however good oak barrels are very expensive and there are difficulties in using them. A more reasonably priced alternative is to use oak chips. The best flavour is achieved by using them during primary fermentation. If desired, 2-3 grams per litre is an appropriate quantity to use in white wine. Simply add them to the must at the beginning of the primary fermentation.
The addition of a Pectic Enzyme (usually known as Pectinase) assists with producing a more free-flowing must. This provides more yield of juice from a given quantity of grapes and improves clarity. It should be used at the rate of 3-4 grams per 5 litres of must and is best added 24 hours before the yeast. It can be added at a later stage, however.
Many people do not like to use sulphur dioxide in making wine. Preservatives quite rightly have received a lot of bad press. However, virtually every commercial winery in the world uses sulphur. Along with neglecting to use a cultured wine yeast, it is the factor that most causes bad wine to be made, and good wine to go bad. The fact is that most sulphur dioxide dissipates during fermentation and storage. If you decide not to use it, be very careful with keeping all of your equipment clean, use grapes that are very fresh and without any visible mould and take care when transferring (racking) from container to container, to reduce the risk of oxidation.
Oxidation results from too much air contact and this is another of the main reasons good wine goes bad. The best way to think of oxidation is to call it spoilage or going stale. When an apple is bitten and goes brown, it is oxidizing. Wine also goes brown with excessive contact with air. It is particularly at risk after fermentation is finished. The two stages when red wine is most vulnerable to oxidation are during transfer as described above, and in storage. It is most important to have minimum contact with air in containers. This is achieved by filling to a narrow neck as oxidation occurs in relation to the surface area contact with air. ie an apple with a big bite out of it will spoil more rapidly than one with a small pinprick. A half full container of wine, whether a small bottle or a large barrel will go bad quickly. The other main technique for reducing the risk of oxidation is using an antioxidant. Potassium metabisuphite is the method most commonly used in white wine making and its use is described elsewhere in this brochure.
Malolactic fermentation converts malic acid in wine into lactic acid resulting in less perception of acidity in the finished wine and a mellower taste. It is used in commercial white winemaking in many wineries these days. Wyeast have a liquid malolactic culture which is easy to use and very effective. The culture is usually added at or near the end of fermentation.
Hand crushers, motorized crusher destemmers, basket presses and
corkers are all available for hire from Grain and Grape.
|
