Flor (Spanish and Portuguese for flower ) in winemaking , is a film of yeast on the surface of wine , important in the manufacture of some styles of sherry . The flor is formed naturally under certain winemaking conditions, from indigenous yeasts found in the region of Andalucía in southern Spain . Normally in winemaking, it is essential to keep young wines away from exposure to air by sealing them in airtight barrels, to avoid contamination by bacteria and yeasts that tend to spoil it. However, in the manufacture of sherries, the slightly porous oak barrels are deliberately filled only about five-sixths full with the young wine, leaving "the space of two fists" empty to allow the flor yeast to take form and the bung is not completely sealed. The flor favors cooler climates and higher humidity, so the sherries produced in the coastal Sanlúcar de Barrameda and El Puerto de Santa María have a thicker cap of flor than those produced inland in Jerez . The yeast gives the resulting sherry its distinctive fresh taste, with residual flavors of fresh bread. Depending on the development of the wine, it may be aged entirely under the veil of flor to produce a fino or manzanilla sherry, or it may be fortified to limit the growth of flor and undergo oxidative aging to produce an amontillado or oloroso sherry.
50-404: During the fermentation phase of sherry production, the flor yeast works anaerobically , converting sugar into ethanol. When all the sugar has been consumed, the physiology of the yeast changes to where it begins an aerobic process of breaking down and converting the acids into other compounds such as acetaldehyde . A waxy coating appears on the cells' exterior, causing the yeast to float to
100-439: A secondary fermentation . Fermentation may be done in stainless steel tanks, which is common with many white wines like Riesling , in an open wooden vat, inside a wine barrel and inside the wine bottle itself as in the production of many sparkling wines . The natural occurrence of fermentation means it was probably first observed long ago by humans. The earliest uses of the word "fermentation" in relation to winemaking
150-409: A bioreactor in which the lining in contact with the cell culture will be plastic , and this lining is encased within a more permanent structure (typically, either a rocker or a cuboid or cylindrical steel support). Commercial single-use bioreactors have been available since the end of the 1990s and are now made by several well-known producers ( See below ) . Single-use bioreactors are widely used in
200-426: A dried or "inactive" state and is reactivated in warm water or diluted grape juice prior to being added to the must . To thrive and be active in fermentation, the yeast needs access to a continuous supply of carbon , nitrogen , sulfur , phosphorus as well as access to various vitamins and minerals . These components are naturally present in the grape must but their amount may be corrected by adding nutrients to
250-520: A family of bioreactors from lab to production that has full scale-up of the bioprocess. Suppliers are working to improve plastic bag materials and performance and also to develop a broader range of sensors and probes that provide scientists greater insight to cell density, quality and other metrics needed to improve yields and product efficacy. New perfusion devices are also becoming popular for certain cell culture applications. Environmental aspects for single-use bioreactors are important to consider due to
300-691: A fundamental role in malolactic fermentation which is essentially the conversion of malic acid into lactic acid . This has the benefit of reducing some of the tartness and making the resulting wine taste softer. Depending on the style of wine that the winemaker is trying to produce, malolactic fermentation may take place at the very same time as the yeast fermentation. Alternatively, some strains of yeast may be developed that can convert L-malate to L-lactate during alcohol fermentation. For example, Saccharomyces cerevisiae strain ML01 ( S. cerevisiae strain ML01), which carries
350-582: A gas barrier. Finally, a contact layer is made from PVA or PP . For medical applications the single-use materials that contact the product must be certified by the European Medicines Agency or similar authorities responsible for other regions. In general there are two different approaches for constructing single-use bioreactors, differing in the means used to agitate the culture medium. Some single-use bioreactors use stirrers like conventional bioreactors, but with stirrers that are integrated into
400-511: A gene encoding malolactic enzyme from Oenococcus oeni and a gene encoding malate permease from Schizosaccharomyces pombe . S. cerevisiae strain ML01 has received regulatory approval in both Canada and the United States. Single-use bioreactor A single-use bioreactor or disposable bioreactor is a bioreactor with a disposable bag instead of a culture vessel. Typically, this refers to
450-416: A result of the commercialization of a drug. This is not always the case, as commercialized drugs can be found being produced in single-use suits/facilities. SUSs contain fewer parts compared with conventional biopharmaceutical manufacturing systems, so the initial and maintenance costs are reduced. Limiting factor for the use of some single-use bioreactors is the achievable oxygen transfer, represented by
500-399: A scale of 1000 Liters volume. Several variations on these two methods exist. The Kuhner Shaker, was originally designed for media preparation, but is also useful for cell cultivation. The PBS Biotech Air Wheel technology uses buoyancy from the air feed to provide rotational power to a stirrer. Measurement and control of a cell culture process using a single-use bioreactor is challenging, as
550-434: A secondary fermentation where sugar and additional yeast known as liqueur de tirage is added to the wine. This secondary fermentation is what creates the carbon dioxide bubbles that sparkling wine is known for. The process of carbonic maceration is also known as whole grape fermentation where instead of yeast being added, the grapes fermentation is encouraged to take place inside the individual grape berries. This method
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#1732848356357600-542: A series of a reaction that convert sugar into alcohol. The discovery of the Embden–Meyerhof–Parnas pathway by Gustav Embden , Otto Fritz Meyerhof and Jakub Karol Parnas in the early 20th century contributed more to the understanding of the complex chemical processes involved in the conversion of sugar to alcohol. In the early 2010s, New Jersey based wine tech company GOfermentor invented an automated winemaking device that ferments in single-use liners similar to
650-422: A single-use bioreactor is not a disposable, but will be continuously reused. The plastic bag that is used instead of a culture vessel is a disposable, as well as all the integrated sub-assemblies like sensors, tubing, and stirrers. The bag and all its parts are mainly made from plastics that are derived from petroleum. Current recycling concepts are mainly focused on incineration, to recover the energy originated from
700-539: Is hártya which means film . Natural yeast film was traditionally used in Gose beer to seal bottles, instead of caps or corks. Flor is also present in Vernaccia di Oristano D.O.C. a wine from the italian region of Sardinia and Malvasia di Bosa. Fermentation (wine) The process of fermentation in winemaking turns grape juice into an alcoholic beverage. During fermentation , yeasts transform sugars present in
750-442: Is assembled, delivered and stored dry, with the consequence that the usual pH-electrodes can not be used. Calibration or additional assembly is not possible. These constraints have led to the development of preconfigured bags with new types of analytical probes. The pH value can be measured using a patch that is just a few millimeters in size. This patch consists of a protecting membrane with a pH-sensitive dye behind it. Changing pH in
800-482: Is common in the creation of Beaujolais wine and involves whole clusters of grapes being stored in a closed container with the oxygen in the container being replaced with carbon dioxide. Unlike normal fermentation where yeast converts sugar into alcohol, carbonic maceration works by enzymes within the grape breaking down the cellular matter to form ethanol and other chemical properties. The resulting wines are typically soft and fruity. Instead of yeast, bacteria play
850-494: Is due to, as stated previously, reduced qualification and validation procedures. This increases productivity and costs due to less resources and time being required for changing from one process to another. Since drugs in the clinical and R&D stage (pre-commercialized drugs) are not needed on the same scale of most commercial drugs, they are often produced in single-use suites so the same area/facility can quickly switch from one drug to another. Often when drug becomes commercialized
900-399: Is fermented between 18–20 °C (64–68 °F) though a wine maker may choose to use a higher temperature to bring out some of the complexity of the wine. Red wine is typically fermented at higher temperatures 20–30 °C (68–86 °F). Fermentation at higher temperatures may have adverse effect on the wine in stunning the yeast to inactivity and even "boiling off" some of the flavors of
950-421: Is the development of chemical residue and spoilage which can be corrected with the addition of sulfur dioxide (SO 2 ), although excess SO 2 can lead to a wine fault. A winemaker who wishes to make a wine with high levels of residual sugar (like a dessert wine ) may stop fermentation early either by dropping the temperature of the must to stun the yeast or by adding a high level of alcohol (like brandy ) to
1000-559: The Saccharomyces cerevisiae (also known as "sugar yeast") species. Within this species are several hundred different strains of yeast that can be used during fermentation to affect the heat or vigor of the process and enhance or suppress certain flavor characteristics of the varietal . The use of different strains of yeasts is a major contributor to the diversity of wine, even among the same grape variety. Alternative, non- Saccharomyces cerevisiae , yeasts are being used more prevalently in
1050-631: The single-use bioreactor . In winemaking, there are distinctions made between ambient yeasts which are naturally present in wine cellars, vineyards and on the grapes themselves (sometimes known as a grape's "bloom" or "blush") and cultured yeast which are specifically isolated and inoculated for use in winemaking. The most common genera of wild yeasts found in winemaking include Candida , Klöckera/Hanseniaspora , Metschnikowiaceae , Pichia and Zygosaccharomyces . Wild yeasts can produce high-quality, unique-flavored wines; however, they are often unpredictable and may introduce less desirable traits to
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#17328483563571100-462: The absence of air. In winemaking, there are different processes that fall under the title of "Fermentation" but might not follow the same procedure commonly associated with wine fermentation. Bottle fermentation is a method of sparkling wine production , originating in the Champagne region where after the cuvee has gone through a primary yeast fermentation the wine is then bottled and goes through
1150-434: The acetaldehyde to be eventually converted, by reduction, to ethanol . During the conversion of acetaldehyde, a small amount is converted, by oxidation, to acetic acid which, in excess, can contribute to the wine fault known as volatile acidity (vinegar taint). After the yeast has exhausted its life cycle, they fall to the bottom of the fermentation tank as sediment known as lees . Yeast ceases its activity whenever all of
1200-419: The advantages of SUSs decrease since one area/facility can be dedicated to one product- essentially eliminating the need for flexibility which is the major advantage of SUSs. It is estimated that ≥85% of pre-commercial drug product production utilizes single-use systems-based manufacturing. Stainless steal reusable systems become more advantageous as the demand for the drug product and batch size increases- often
1250-409: The amount of disposable material used compared with conventional bioreactors. A complete life cycle assessment comparing single-use bioreactors and conventional bioreactors does not exist, but many ecological reasons are supporting the concept of single-use bioreactors. For a complete life cycle assessment not only the manufacturing, but also the repeated use need to be considered. Even the main part of
1300-410: The bag in which the cultivation will be performed is a closed and pre-sterilized system. Sensors for measuring the temperature, conductivity, glucose, oxygen, or pressure must be built into the bag during the manufacturing prior to sterilization. The sensors can’t be installed prior to use of the bioreactor as in the conventional case. Consequently, some challenges must be taken into consideration. The bag
1350-563: The contact of product to non-single-use parts/systems. Compared with conventional bioreactor systems, the single-use solution has some advantages. Application of single-use technologies reduces cleaning and sterilization demands. Some estimates show cost savings of more than 60% with single use systems compared to fixed asset stainless steel bioreactors. In pharmaceutical production, complex qualification and validation procedures can be made easier, and will finally lead to significant cost reductions. The application of single-use bioreactors reduces
1400-455: The culture medium changes the pH, and the color, of the dye. The color change can be detected with a laser external to the bag. This and other methods of non-invasive measurement have been developed for single-use bioreactors. Decreasing product contact with parts/systems decreases qualification and validation times when changing from one drug process to another. Since the biopharmaceutical manufacturing process includes many steps other than just
1450-420: The culture vessel need to be cleaned and sterilized after each fermentation . Cleaning requires large amounts of water, in addition to acids, alkali and detergents. Sterilization with steam at 121 degrees C and 1 bar pressure requires large quantities of energy and large amounts of distilled water. This distilled water (often called "water for injection" in pharmaceutical nomenclature) must be prepared by expending
1500-501: The effect during fermentation of releasing glycoside hydrolase which can hydrolyse the flavor precursors of aliphatics (a flavor component that reacts with oak ), benzene derivatives, monoterpenes (responsible for floral aromas from grapes like Muscat and Traminer ), norisoprenoids (responsible for some of the spice notes in Chardonnay ), and phenols . Some strains of yeasts can generate volatile thiols which contribute to
1550-429: The field of mammalian cell culture and are now rapidly replacing conventional bioreactors. Instead of a culture vessel made from stainless steel or glass, a single-use bioreactor is equipped with a disposable bag. The disposable bag is usually made of a three-layer plastic foil. One layer is made from Polyethylene terephthalate or LDPE to provide mechanical stability. A second layer made using PVA or PVC acts as
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1600-446: The fruity aromas in many wines such as the gooseberry scent commonly associated with Sauvignon blanc . Brettanomyces yeasts are responsible for the "barnyard aroma" characteristic in some red wines like Burgundy and Pinot noir . Methanol is not a major constituent of wine. The usual concentration range is between 0.1 g/liter and 0.2 g/liter. These small traces have no adverse effect on people and no direct effect on
1650-408: The industry to add greater complexity to wine. After a winery has been in operation for a number of years, few yeast strains are actively involved in the fermentation process. The use of active dry yeasts reduces the variety of strains that appear in spontaneous fermentation by outcompeting those strains that are naturally present. The addition of cultured yeast normally occurs with the yeast first in
1700-429: The introduction of active yeasts to the grape must, phosphates are attached to the sugar and the six-carbon sugar molecules begin to be split into three-carbon pieces and go through a series of rearrangement reactions . During this process, the carboxylic carbon atom is released in the form of carbon dioxide with the remaining components becoming acetaldehyde . The absence of oxygen in this anaerobic process allows
1750-466: The juice into ethanol and carbon dioxide (as a by-product ). In winemaking , the temperature and speed of fermentation are important considerations as well as the levels of oxygen present in the must at the start of the fermentation. The risk of stuck fermentation and the development of several wine faults can also occur during this stage, which can last anywhere from 5 to 14 days for primary fermentation and potentially another 5 to 10 days for
1800-410: The must to kill off the yeast and create a fortified wine . The ethanol produced through fermentation acts as an important co-solvent to the non-polar compound that water cannot dissolve, such as pigments from grape skins, giving wine varieties their distinct color, and other aromatics. Ethanol and the acidity of wine act as an inhibitor to bacterial growth, allowing wine to be safely kept for years in
1850-447: The petroleum as heat and electricity. Most of the petroleum would be burned anyway in power plants or automobiles (citation required). Burning of the single use components of bioreactors creates a detour through biochemical engineering during their life cycle that does not have a big influence. The making of conventional culture vessels form stainless steel or glass requires more energy than making plastic bags. Using conventional bioreactors
1900-421: The plastic bag. The closed bag and the stirrer are pre-sterilized. In use the bag is mounted in the bioreactor and the stirrer is connected to a driver mechanically or magnetically. Other single-use bioreactors are agitated by a rocking motion. This type of bioreactor does not need any mechanical agitators inside the single-use bag.,. Both the stirred and the rocking motion single-use bioreactors are used up to
1950-599: The point of becoming vinegar . Above 16% the flor cannot survive, and so the wine essentially becomes an oloroso . A film of yeast similar to flor is also used in the production of vin jaune in the Jura wine region in eastern France . The French term used for this yeast film is voile , meaning " veil ". A similar yeast to flor is used in the production of Szamorodni szaraz in the Tokaj wine region in northeastern Hungary and southeastern Slovakia . The Hungarian name for this yeast
2000-730: The risk of cell damages. Single-use bioreactors are currently available with up to a volume of about 1000 L; that’s why scale up is limited compared to conventional bioreactors. However, a handful of suppliers are now delivering units at the 2,000 liter scale and some suppliers (Sartorius, Xcellerex, Thermo Scientific HyClone and PBS Biotech) are providing a family of single-use bioreactors from bench-top to full-scale production. Three challenges exist for faster and greater single use bioreactor adoption 1) higher quality and lower cost disposable bags and containers, 2) more reusable and disposable sensors and probes that can provide high quality analytics including real-time cell culture level data points, and 3)
2050-412: The risk of cross contamination and enhances the biological and process safety. Single-use applications are especially suitable for any kind of biopharmaceutical product. A major reason single-use bioprocessing (SUS) is popular with pharmaceutical companies and contract manufacturing organizations (CMOs) is because a process area/facility can quickly change from one process (drug product) to another. This
Flor - Misplaced Pages Continue
2100-416: The senses. During fermentation, there are several factors that winemakers take into consideration, with the most influential to ethanol production being sugar content in the must, the yeast strain used, and the fermentation temperature. The biochemical process of fermentation itself creates a lot of residual heat which can take the must out of the ideal temperature range for the wine. Typically, white wine
2150-463: The specific mass transfer coefficient (k L ) for the specific phase area (a), resulting in the volumetric oxygen mass transfer coefficient (k L a). Theoretically this can be influenced by a higher energy input (increasing the stirrer speed or the rocking frequency). However, since single-use bioreactors are mainly used for cell culturing, the energy input is limited by the delicate nature of cells. Higher energy input leads to higher shear forces causing
2200-654: The sugar in must has been converted into other chemicals or whenever the alcohol content has reached 15% alcohol per unit volume; a concentration strong enough to halt the enzymatic activity of almost all strains of yeast. The metabolism of amino acids and breakdown of sugars by yeasts has the effect of creating other biochemical compounds that can contribute to the flavor and aroma of wine . These compounds can be considered " volatile " like aldehydes , ethyl acetate , ester , fatty acids , fusel oils , hydrogen sulfide , ketones and mercaptans or "non-volatile" like glycerol , acetic acid and succinic acid . Yeast also has
2250-415: The surface and form a protective "blanket" thick enough to shield the wine from oxygen . This process drastically lowers the acidity of the wine and makes sherry one of the most aldehydic wines in the world. Studies have shown that for the flor to thrive, the wine must stay in a narrow alcohol range of 14.5% to 16% ABV . Below 14.5% the yeast will not form its protective cap, and so the wine will oxidize to
2300-417: The use of bioreactors, single-use technologies are utilized throughout the manufacturing process due to its advantages. Single-use bioprocessing (SUS) steps available are: media and buffer preparation, cell harvesting, filtration, purification and virus inactivation. The major innovation of single-use technologies in this area of processing has been in the construction of 2D/3D bags and tubing wielding- reducing
2350-483: The wine, and can even contribute to spoilage. Few yeast, and lactic and acetic acid bacterial colonies naturally live on the surface of grapes, but traditional wine makers, particularly in Europe, advocate use of ambient yeast as a characteristic of the region's terroir ; nevertheless, many winemakers prefer to control fermentation with predictable cultured yeast. The cultured yeasts most commonly used in winemaking belong to
2400-409: The wine, in order to foster a more encouraging environment for the yeast. Newly formulated time-release nutrients, specifically manufactured for wine fermentations, offer the most advantageous conditions for yeast. Oxygen is needed as well, but in wine making, the risk of oxidation and the lack of alcohol production from oxygenated yeast requires the exposure of oxygen to be kept at a minimum. Upon
2450-545: The wines. Some winemakers may ferment their red wines at cooler temperatures, more typical of white wines, in order to bring out more fruit flavors. To control the heat generated during fermentation, the winemaker must choose a suitable vessel size or else use a cooling device. Various kinds of cooling devices are available, ranging from the ancient Bordeaux practice of placing the fermentation vat atop blocks of ice to sophisticated fermentation tanks that have built-in cooling rings. иьИс A risk factor involved with fermentation
2500-400: Was in reference to the apparent "boiling" within the must that came from the anaerobic reaction of the yeast to the sugars in the grape juice and the release of carbon dioxide. The Latin fervere means, literally, to boil . In the mid-19th century, Louis Pasteur noted the connection between yeast and the process of the fermentation in which the yeast act as catalyst and mediator through
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