Making Wine: Topping Up and Rackings

 One of the main preoccupations of whoever makes wine is to prevent the development of faults which could compromise the quality of the finished product. To obtain this result, it is necessary to adopt specific measures and techniques in order to ensure the wine the best possible biological stability. At the end of fermentation, wine is not limpid and crystalline the way we are used to see it in our glasses after we pour it from the bottle. Making a wine limpid takes time, a process that - among the other things - is favored by many conditions which can also be obtained by means of the biological stability of wine. The operations of topping up and rackings are considered fundamental in order to obtain a good wine, stable, with no faults and fine: that's why it is usually said rackings are the fundamental secret to obtain perfect wines. At high quantities, oxygen is an enemy of wine, therefore it will be paid attention on avoiding its contact as much as possible, a condition which can be easily obtained by means of topping up.

With time, wine in a cask will tend to diminish, therefore it is necessary to periodically do topping up operations

 Among the preoccupations of whoever makes wine, there is also how to keep it in the best possible condition, in order to avoid the development of faults and to ensure the best possible biological stability. The choice of the containers to be used for the keeping, their use, temperature and humidity, are among the main factors ensuring the best conditions of stability, from aging to bottling. Wine is a live product which comes to the world, grows up and, finally, dies. This “biological” cycle is widely influenced by many factors ensuring the longest and best possible life, of course, according to the type of wine. The lack of optimal conditions or neglecting the “health” of the wine, will cause not only a sick condition, but also its premature death. The operations of topping up and rackings, which we will discuss later, are fundamental procedures to obtain a good wine, however not enough in case are not adopted good conditions of keeping.

 In “industrial” wine making, or however in most of commercial wineries making wine, stability of wine is also obtained by means of other procedures, not always possible in home making, both because of their cost, as well as for practical reasons. Among the many, pasteurization and filtering which can be obtained by using specific tools and which ensure the best biological stability of wine by removing negative bacteria and suspended particles. Despite these two techniques are frequently used in the commercial production of wine, indeed their use is frequently debated and in some case they are avoided in order to keep the wine as much “genuine” as possible. In fact, pasteurization and filtering allow the elimination of some unwanted substances from the wine and which could be cause of faults or spoilage, however these operations also remove other substances that - as a matter of fact - impoverish the wine although ensuring a better biological stability.

 In home wine making we can certainly avoid both pasteurization and filtering, however it is essential the fundamental condition for the keeping and the health of the wine are ensured. As we said in previous articles, hygiene and cleanliness of the containers used in the many phases of wine making is essential. It will also be essential in the room used for the keeping are found the fundamental hygienic conditions in order to avoid the spoilage of containers used for keeping the wine - in particular wood containers - and which could compromise the stability of wine. For this reason, after the operations of racking - and in case it is necessary, after the operation of topping up - it is important to clean the room, in particular the floor, and all the tools used. Despite Louis Pasteur defined wine as “the most healthy and hygienic of beverages”, this does not mean such conditions spontaneously happen, moreover, it should be remember wine is swallowed: another good reason to pay attention on hygiene.

 Oxygen is a friend-enemy of wine, a role determined according to the quantity and surface in contact with it. In very reduced quantities, the action of oxygen is useful for the aging of wine, something which happens - for example - in the cask. In fact, oxygen passes through the pores of the wood and reaches the inside of the cask, therefore coming in contact with the wine. However the quantity received this way is very low, favoring - as a matter of fact - a micro oxygenation indispensable for the chemical and organoleptic development of wine. In excessive quantities, it causes the oxidation of wine's components, with negative and unpleasing effects according to an organoleptic point of view. Oxygen is also a “friend” during tasting as it allows, also favored by the swirling of the glass, the development and perception of wine's aromas. During production it is however considered an “enemy” and its contact with the wine will be avoided as much as possible.

 No matter the type of container used for the keeping of wine, it is fundamental the direct contact with oxygen is avoided as much as possible. For this reason, no matter the type of container - demijohn, cask, barrique, steel or cement tanks - it is essential they are always topped up and full: a condition which avoids the contact with oxygen. When the wine is poured in the keeping container, it will be important to fill it as much as possible, by leaving the least possible space between the cap and the level of the wine. During the keeping, changes of temperature and season will cause rises and lowering of the level, therefore changing the surface in contact with oxygen while increasing the risks of oxidation. Moreover, in case of cask, part of the wine passes through the pores of the wood, therefore diminishing the level inside of it and increasing, at the same time, the surface in contact with oxygen. For this reason, at least once every two weeks, we will check the level of the wine inside the keeping containers and we will do, according to needs, topping up by adding wine up to reaching a “safe” level.

 For the topping up will be used the same wine kept in a small container - for example, a small demijohn - which will be however kept in good conditions by avoiding the contact with the air, by covering its surface, for example, with a layer of vaseline oil. For the topping up of large containers, such as casks and tanks, it is convenient the use of specific topping up caps - available in shops specialized in wine making items and which can also be used as air-locks during fermentation - which allow an easy check of the level of wine and to see when a topping up is needed. Topping up cap is mounted in the cask's bung and therefore it is filled with wine, therefore it is sealed with its cap. When needed, new wine is added to the topping up cap, therefore keeping the cask full. For small containers, such as demijohns, they must be completely filled up to few centimeters below the opening, then it is poured some vaseline oil, therefore isolating the wine from the contact with the air.

 It is said rackings are the secret for obtaining perfect wines and the experience teaches us this is true. In fact, by means of rackings it is possible to obtain very limpid wines, allowing the removal of unwanted solid and negative substances, therefore quality wines according to an organoleptic point of view. At the end of fermentation, the wine is turbid and with many suspended particles that, besides compromising the appearance, they can, with time, cause faults and spoilage. These solid substances in suspension - mainly made of yeast cells, residual of grape skins and pulp - will deposit on the bottom of the container, therefore, by means of rackings, we will separate the limpid part from the solid one. The precipitation of solid substances also happens after some weeks from every racking, a phenomenon therefore requiring the repetition of this procedure. With every racking is obtained a more stable and limpid wine, refined and perfect, therefore - according to the type of wine and its consumption - this operation will be done periodically during aging and before bottling.

 Rackings can be considered a natural clarification method, a process with which - by means of sedimentation of solid substances - it is possible to obtain a limpid and clear wine. As already mentioned, these solid substances are made of yeast cells, residuals of grape's skin, pulp and pips, more or less soluble salts, such as potassium bitartrate, and - in case of red wines - coloring substances and polyphenols. These substances will deposit on the bottom of the container and will make the so called lees that, in contact with the limpid wine, can be cause of spoilage and faults. In fact, lees contain micro organisms which could cause faults in wine, moreover, they can be the place for chemical reactions, in particular in the condition of “reduction”, that is in absence of oxygen. In this specific case could develop unpleasing aromas and tastes, such as sulphydric acid, a smell recalling “rotten eggs”, or mercaptan, recalling the smell of garlic. The presence of lees can also be cause of haziness in case they are moved and suspended in the wine. For all these reasons, lees must be removed from the wine by means of rackings.

 In wine making, there are two types of rackings, used according to the conditions of the wine and its health. Open racking, or racking in contact with air, and close racking, or racking with no contact of the air. Open racking is done by transferring the limpid part of the wine in an open container which is then immediately transferred to the destination container. This procedure allows the wine to oxygenate and it is useful in case there are unpleasing smells - in particular at the end of fermentation - which can be removed by this procedure. Close racking is done by avoiding any contact of the wine with the air, by connecting the two containers with a pipe and with which will be transferred the limpid wine to the destination container. According to the type of container, the racking can be done by using a wine pump with which the wine will be transferred from one container to another, or, in case of small containers, it can be used a siphon. It is essential the part of the pipe with which the wine is drawn off is far above the sedimented lees, as - besides making the wine turbid - it must not be transferred to the destination container, of course.

 The first racking is usually done in contact with the air, in order to favor the elimination of any possible unpleasing smell, whereas all the other rackings are usually done with no contact of the air. The racking with no contact of the air must be however done when the test of the air - described in previous articles - gives a negative result, that is in case the wine is not very resistant to the air and which can easily oxidize or spoil. After every racking, the volume of the wine diminishes - because of the removal of the lees - therefore at the end of this operation, the destination container will be topped up. The quantity of rackings and their periodicity vary according to the type of wine and the aging cycle. During the first year are usually done three or four rackings. The first racking is done after two or three weeks from the racking following the end of fermentation, in order to separate the wine from gross lees. In case a wine was made with spoiled grapes or having evident signs of mold or rot, it is best to do the first racking in advance, in order to remove bacteria and pathogen micro organisms.

 The second racking is generally done at the beginning of winter, after the arrive of the cold which will favor the precipitation of solid substances and potassium bitartrate. The third racking is done at the beginning of spring, in the period from March to April. At this point, white wines not destined to aging can be bottled, whereas for red wines and white wines destined for aging, will be done - when necessary - a fourth racking before the arrival of summer, generally in the period from June to July. When necessary, it will be done a fifth racking with the arrive of autumn. In the following years, according to the type of wine, will generally be done two rackings per year. It should be remembered that during the aging of wine and rackings, the quantity of free sulfur dioxide diminishes, therefore it is recommended to replace the lost part by adding 2 or 3 grams of sulfur dioxide for every one hundred liters of wine (4 or 6 grams of potassium metabisulfite for every one hundred liters). Finally, it is good to remember the containers receiving the wine must be clean and washed with a sulphurated solution, as described in previous articles. A final consideration about weather conditions: rackings are always done with clear sky and dry weather, when the pressure is high. Otherwise, gases dissolved in wine will tend to get free, causing the suspension of the lees and therefore making the wine less limpid.