633:) which changes color depending on the acid levels of the solution. The indicator is added to the grape juice followed by incremental amounts of the alkaline solution as the wine changes color until adding more of the solution ceases to promote a color change. At this point the wine has been neutralized with the amount of the alkaline solution needed to neutralize calculated in a formula to give an indication of how much tartaric acid was in the wine. The TA level is then expressed in a percentage of grams per 100 milliliter. As with must weight, the ideal levels for ripeness will vary according to wine style and winemaking preference. For still table wines, TA levels often fall between 0.60-0.80% for red wine grapes and 0.65-0.85 for whites.
142:
800:
with the actual amount of anthocyanin content in a sample. To use with grapes, the skin is removed and placed across the sensor of the meter. Measurements take only a second or two. These
Anthocyanin Content Meters use an additional Near Infra-Red (NIR) signal, which takes into account the thickness of the sample, along with the absorbance wavelength to calculate a very accurate index value which is repeatable and consistent enough for comparative testing. A new method just being explored is to dip a piece of filter paper into a solution/sample to be measured and put that across the sensor head as the test sample. There have been positive reports on the second method, but they have not been published.
576:
to the most unusual elements. The must weight is then plotted on a chart to see the increasing ripeness and sugar levels of the grape. What must weight reading is most desirable will depend on the winemaker's personal goal for ripeness. A wine with the intended potential alcohol level of 12% will need to be harvested at around 21.7°Bx/12 degree Baumé/93°Oe. A wine with the intended potential alcohol level of 15% will need to be harvested at around 27.1°Bx/15 degree Baumé/119°Oe. The desired ripeness for most table wines tend to fall somewhere between those two must weight measurements.
418:. It is much more difficult to remedy the effects of extensive rains during the ripening period. Steady rains before the harvest can cause the berries to swell with water which dilutes the flavors as well as causing cracking in the skin that creates openings for spoilage causing microorganism to propagate. Because of these risks, the threat of prolong rainfall during a vintage may cause an early harvest before the grapes have fully ripened. The most favorable vintages allow a slow, steady ripening without drastic jumps in heats or the threat of excessive rain fall.
258:
476:
642:
779:
728:
585:
683:
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414:, particularly as it nears harvest, can cause the sugars in grapes to jump as acids fall dramatically. Some winemakers may decide to harvest early in order to maintain acid levels even though other components (such as tannins and phenolic compounds) may not be at optimal ripening. For the winemakers that decide to "wait it out", a lack of acid can be partially rectify during the winemaking process with the addition of acids such as
31:
719:
then multiply that number by the Brix reading. Using this method, when white wine grapes gets close to 200 and red wine grapes close to 260, it can be a good rule of thumb of when to harvest. For example, white wine grapes have a pH of 3.3 and Brix of 20, after going through that formula they will have a finally number of 217.80 which is well within an acceptable harvest range for some winemakers.
393:
674:
grapes are overripe (or that the soil has too much potassium which will also influence pH readings). While there are risks to letting the pH go too high, winemakers can counter high pH by adding more tartaric or malic acid during the winemaking. However, many viticulturists and winemakers uses pH readings as a strong boundary line for when to start the harvest.
430:
needed to ensure that the grapevine can produce enough energy to support all its physiological functions, but too much leaf cover will shade the grape clusters, limiting the direct exposure of sunlight and warmth needed for some chemical components of the grapes to develop. An excessive amount of foliage and shading may also promote the development of various
484:
the purpose of harvesting at point when each number reaches its most ideal range for the type of wine being produced. In recent years, viticulturists and winemakers have shifted away from focusing purely on those numbers towards considering other factors including the ripeness of tannins, the development of flavor precursors and the potential for
76:, etc.) and what the winemaker and viticulturist personally believe constitutes ripeness. Once the grapes are harvested, the physical and chemical components of the grape which will influence a wine's quality are essentially set so determining the optimal moment of ripeness for harvest may be considered the most crucial decision in winemaking.
765:
with different stages of development. They evaluate the skin and pulp texture of the berry as well as the color of skins, seeds and stems. If the seeds are still green, the tannins inside the grape are more likely to be harsh and bitter. As the tannins continue to develop, the seeds start darkening in color. They will observe the
654:
fall, the concentration of acids are lessening which means the pH level is rising. Yeasts, bacteria, phenolic compounds such as anthocyanins which influence color all have varying tolerance to wines with high pH levels. In general, wines with high pH value tend to have duller colors and less developed flavors and be more prone to
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The most ideal situation for a viticulturist or winemaker is to have the sugar, acidity and pH levels to be perfectly balanced at the time of harvesting. One hypothetical ideal for still red table wine is to have grape measurements reading 22 Brix, 0.75 TA and 3.4 pH. As author and winemaker Jeff Cox
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ions. It is related to the titratable acidity level of a wine but differs in significant ways. Low pH numbers indicate a high concentration of acids in a solution. While pure water is neutral with a pH of 7, wine tends to be more acidic with a pH between 3 and 4. As the acid levels in ripening grapes
735:
The idea of physiological ripeness (or physiological maturity) of grapes is a relatively recent addition to the discussion of ripeness in viticulture and winemaking. It is a broad category of factors in the development of ripening grapes that affect a wine's quality beyond the standard measurements
575:
has begun, viticulturists will test several hundred individual berries picked from clusters throughout the vineyard in increasing intervals as the harvest draws closers. The berries will usually be taken from the middle of the cluster bunch, avoiding vines on the end of rows that tend to be exposed
483:
As "ripeness" constitutes a variety of factors, there are many methods that viticulturist and winemakers may use in order to determine when the grapes are sufficiently ripe to harvest. The most common method of determining ripeness involves measuring the sugar, acid and pH levels of the grapes with
429:
can also play a significant role as it not only influences the physiological processes of the grapevine but also how the vine responds in sharing its limited resources of energy and nutrients. The leaves of a grapevine produce energy via the process of photosynthesis. A certain amount of foliage is
799:
Recently, similar methods to determine chlorophyll content in leaves non-destructively have been applied to measuring anthocyanin content. There are now a couple of optical absorbance instruments available commercially which are designed to measure and compute an index value that correlates highly
718:
of brix degrees to the TA measurements. For example, a wine with 22°Bx and .75 TA will have almost a 30:1 Brix:TA ratio. According to the Davis researchers, the most balanced table wines tend to have a Brix to TA ratio between 30:1 - 35:1. Another method is to multiply the pH reading by itself and
596:
so its presence in wine is important with winemakers trying to harvest grapes before acid levels fall too low. The stress to maintain acid levels is not as bearing due to the fact that winemakers can rectify the situation somewhat by later adding acids during the winemaking process (winemakers can
442:
which can hamper the ripening process. A very vigorous vine with many clusters and vine shoots will have several parties competing for the same resources, with the overall development of an individual clusters thus slowed. Through the process of canopy management, viticulturists try to balance not
405:
and temperature warmth are vital to the physiological functions of the grapevine (such as photosynthesis). An absence of either, such as long periods of extensive cloud cover, will cause many functions of the vine to slow or even completely halt as the vine enters a type of "survival mode". As the
265:
What constitutes "ripeness" will vary according to what style of wine is being produced as well as the particular views of winemakers and viticulturists on what optimal ripeness is. The style of wine is usually dictated by the balance between sugars and acids. What may be considered "ripe" for one
764:
For the most part, many of these qualities are difficult to objectively measure so evaluation of the physiological ripeness of grapes is centered around observing and physically sampling the grapes. With experience winemakers and viticulturists learn to associate certain taste and characteristics
248:
known as "flavor precursors" which contribute to the eventual flavor and aroma of the wine also begin to build up in the skins and pulp. Additionally the concentration of tannins in the grape increases in several areas of the grape including the skin, seeds and stem. Early in the ripening process
673:
that can give readings to an accuracy of plus or minus 0.1. As with sugars and acids, the ideal pH levels to determine ripeness will vary. For white wines, winemakers often look for pH readings between 3.1 and 3.2, while would be a maximum of 3.4. If the pH is too high, it may be a sign that the
769:
of the stems as they turn from being flexible and green to hard, woody and brown (for many varieties but not all) indicating that vine has completed its work in developing its "offspring" grape clusters and has started to store carbohydrates and resources for its next growing season. During the
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which occur late in ripening as the buildup of sugars have leveled. This stage is distinct from the sugar/acid interactions of ripening because it is possible for a grape to be "ripe" in the context of sugar and acid levels but still be very immature when it comes to the development of tannins,
620:
or "TA" (also referred to as "total acidity") is the measure of the tartaric acid in the grapes. This is the most abundant acid and also the one acid that has the most pronounced and long lasting impact on the taste of the wine. The TA is often measured by neutralizing some grape juice with a
376:, maintaining a certain amount of acidity in the grapes is important to the winemaking process. As the concentration of acids in the grapes decreases the further along the ripening process you go, grapes destined for sparkling wines are often some of the earliest grapes to be harvested in a
736:
of sugars, acids, and pH. These factors generally include evaluating the ripeness of tannins as well as the development of other phenolic compounds that contribute to the color, flavor, and aroma of wine. In many ways, the concept of physiological ripeness is similar to the
368:
and phenolic compounds that produce various aromas in wine that contribute to a wine's flavor profile. For this reason, some winemakers will value having a higher potential alcohol level and delay harvesting until the grapes have a sufficiently high concentration of sugars.
786:
While it is difficult to objectively measure the qualities of physiological ripeness, researchers in the wine industry have been continuing pursuing methods that give some indication of the grapes development in these areas. For instance, some wineries have started using
601:). However, natural acids in the grape play other roles in the development of flavor and aroma compounds as well as fighting against the effects of spoilage organisms so the most ideal situation for winemakers is to try and harvest while acid levels are acceptable.
703:, grape varieties, vineyard management and the general characteristics of the vintage, winemakers learn to find a compromise between all these component readings and select the point of ripeness that is most align with their vision for the end product wine.
848:, creating glycosides. These compounds are released during the late stages of winemaking and aging, when they augment or enhance flavor compounds. Theoretically, grapes with more flavor precursors have the potential to produce higher quality wine.
173:, which may last from 30–70 days depending on the climate and other factors, the grapes go through several changes which impact their sugar, acid, tannin and mineral composition. The concentration of phenolic compounds in the skin, most notably
396:
Vineyard management techniques such as canopy management can influence the ripening process of grapes by balancing the amount of foliage needed for photosynthesis versus excessive foliage that shades the grapes and competes for the grapevine's
863:
per liter or per grape berry. The relationship between the presence of glycosides in wine grapes and the potential for quality in the resulting wine is not exact science but this remains an area of continuing research and development.
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to determine the concentration of color producing anthocyanins in the skins of grapes. A sizable amount of research has gone into studying methods to determine the presence of flavor precursors and glycosides in the ripening grapes.
406:
grapevine funnels more resources to preserve its own survival, less resources are directed towards the ripening and development of the grape clusters. Excessive heat can also cause a grapevine to react adversely. The occurrence of
859:. Through this method glycosides from the grape juice are isolated and then hydrolysized to yield glucose. The amount of glucose produced is then quantified and tabulated in results that are expressed as amount of glycosides in
446:
Even if climate and vineyard management has been ideal, other factors may prevent full and even ripeness. Among the clusters of a grapevine, individual berries may not all ripen at the same pace. This problem, commonly known as
239:
increase in concentration as they are disseminated among the skin of the grapes and its fleshy pulp. The color of the grape berries begins to change due to the building up of phenolic compounds such as anthocyanin in the skins.
249:
these tannins are very bitter and "green". Exposure to the warmth and sunlight during the ripening period ushers in chemical changes to the tannins that when processed into wine makes the tannins feel softer in the mouth.
380:. With their high acidity and low sugar levels, these grapes would be underripe and would produce table wines that many wine drinkers would consider unpalatable, yet the balance of sugars and acids is well suited for
803:
Flavor precursors are flavorless compounds that occur naturally in grapes as the result of normal metabolic activity of the grape vine. They are more abundant in grapes than the phenolic compounds known as
443:
only the amount of clusters and vine shoots on the vine but also try to achieve an optimal balance of needed foliage for photosynthesis without excessive shading that could hamper the ripening process.
321:. The greater the concentration of sugars in the grape, the greater the potential alcohol level. However, most strains of winemaking yeast have difficulties surviving in an alcohol solution above 15%
204:
molecules. The rate of this build up will depend on several factors including the climate (such as a string of cloudy weather which prohibits sunlight from reaching the vine) as well as the potential
340:) in the wine contributes much more than just healthful benefits in moderation and minimal consumption, prudently applied, or, negative effects in excess. It has an immense impact of the
592:
As sugar levels in the grape rise, acid levels fall. All wines need some degree of acidity in order to be balanced and avoid tasting flabby or dull. Acidity is also a key component in
528:
in the winery with the juice from several dozen or hundreds of grape berries. Different countries around the world use various scales to measure the must weight of grape juice. In the
706:
There are several formulas that viticulturist and winemakers can use that utilize the various measurements of sugar, acid and pH level. One method developed by researchers at the
149:. As the grapes ripen, the concentration of phenolic compounds like anthocyanins replaces the green color of chlorophyll in the grape berries which makes them black instead.
227:
In addition to the change in sugar, acids and pH levels of other components of the grapes are building up during the ripening process. The mineral components of potassium,
731:
In determining physiological ripeness, winemakers will observe the lignification of the grape stems as they turn from being flexible and green to hard, woody and brown.
313:
as well as the potential alcohol level of the wine will play a considerable role in dictating when a grape is "ripe" enough. This is because sugars are converted by
113:
of the grapes, are evaluated to determine ripeness. Towards the end of the 20th century, winemakers and viticulturists began focusing on the concept of achieving "
851:
Scientists have discovered it is possible to determine, to some extent, the presence of these compounds in the grape before harvest. One way is to measured with
212:
which compete for the resources of the mother grapevine. As the concentration of sugars builds up, the concentration of acids decreases due, in part, to simple
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ripening period winemakers and viticulturists will continually sample grapes throughout the vineyard in the weeks and days leading up to harvest.
421:
The role that climate plays in influencing the ripening process cannot be overstated, but it is not the only factor. Vineyard management such as
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or taste), the stage of ripening when aroma and flavor become apparent. Research has shown that most aroma compounds develop in the berry in
153:
If ripening is broadly defined as the development of wine grapes, then it could be said that ripening is happening throughout the continuous
1518:
974:
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caused by spoilage organisms which makes monitoring the pH levels of grapes during ripening a priority for viticulturists and winemakers.
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or "flavor precursors". These compounds are found in trace amounts, and measured in parts per trillion. Through the action of acids and
261:
Pinot noir grapes that are destined for sparkling wine will be considered ripe much earlier than Pinot noir destined for still red wine.
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1044:
832:. When these components are "free" they are known as "flavor compounds" but when they combine with sugars in the grapes, they become
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to development. A combination of these factors apart from sugar, acid and pH are considered "physiological" ripeness of the grape.
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winemaker could be considered underripe to another winemaker or even overripe to yet a third winemaker. Climate and the particular
669:, the results are usually not as detailed and accurate as what is needed to evaluate ripeness. Therefore, most wineries will us a
165:
though it may be longer in cooler climates), the grapes are hard and green with low sugar levels and very high levels of mostly
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329:
which influences the sweetness level of the wine. Wines that are destined to be sweet, such as dessert wines, are often called
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Winemakers use a refractometer on samples of grapes picked in the vineyard to measure sugar levels while determining ripeness.
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because they are harvested at extreme points of ripeness much later than when regular table wine grapes have been harvested.
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will also play a role in determining ripeness and date of harvest. In very hot climates, such as certain areas in
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325:(ABV) and cease fermentation before all the sugar is converted into alcohol. This leaves a certain amount of
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1021:
Practical Winery and
Vineyard, Department of Enology & Viticulture, UC Davis, July/August issue 2001
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to the harsh effects of acids and tannins, making the wine seem softer. It also plays a role during the
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One of the primary factors influencing the ripening process of grapevine is the climate and weather.
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produced by photosynthesis is transferred from the leaves to the berries as it is broken down into
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101:) and acids is considered one of the most critical aspects of producing quality wine so both the
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There are several factors that contribute to the ripeness of the grape. As the grapes go through
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period of the grape but can also be caused by soil deficient in various nutrients such as
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Researchers in the wine industry are developing new ways to objectively measure ripeness.
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to indirectly measure the must weight from the juice of a single grape or they can use a
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Since more than 90% of all the dissolved solids in grape juice are sugars, measuring the
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318:
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Third
Edition pg 255–274, 317–324, 397, 523–524, 582-581 Oxford University Press 2006
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294:. The ripening periods for each individual grape variety will vary with grapes such as
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of winemaking that is rarely dealt to winemakers. With all the variables of climate,
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Grapes that have been left on the vine too long may become over ripe and dehydrated.
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While the rudimentary method of testing pH is to expose the grape juice to a
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in the roots and trunk of the grapevines as well as through the process of
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taking much longer to ripen compared to early ripening varieties such as
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54:. What exactly constitutes ripeness will vary depending on what style of
47:
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aromas and flavor that are characteristic of a complex or quality wine.
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of the wine as well as the balance of sweetness, tannins and acids. In
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209:
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The principle acids found in wine grapes are tartaric and malic acids.
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1221:
1139:
824:, which contributes to the "green-bell pepper" aroma associated with
649:
The pH level of a wine is the measurement of the amount of free (H+)
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435:
345:
309:
Since over the course of ripening sugars in the grapes increase, the
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162:
1564:
1338:
1186:
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81:
43:
117:" ripeness in the grapes-described as a more complete ripeness of
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1206:
837:
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The pH levels for most wine fall between 3 and 4 on the pH scale.
505:
422:
377:
337:
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197:
193:
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of the juice is measured in relation to the specific gravity of
68:
30:
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or a number of other factors that may contribute to incomplete
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357:
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The increase of sugars in the grapes comes from the storage of
1050:
252:
1314:
1150:
1112:
1045:
Fruit
Maturity Evaluation of Wine Grapes for Harvest Planning
715:
456:
392:
157:. More narrowly defined, ripening begins at the inception of
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1416:
1371:
947:
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937:
935:
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504:. Rather than measure the actual "weight" of the must, the
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55:
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927:
925:
923:
921:
919:
917:
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913:
27:
How the term "ripe" is used in viticulture and winemaking
220:. The decrease in free acids, as well as the buildup of
910:
372:
For other types of wines, such as sparkling wines like
216:
but also to the consumption of acids in the process of
136:
110:
459:, an attack of various grapevine ailments such as the
224:, triggers a rise in the pH level of the grape juice.
278:, ripeness is usually achieved around 30 days after
161:. At this point (which is normally 40–60 days after
773:
356:qualities of ethanol reduce the sensitivity of the
900:Fourth Edition, pg 97-106 Storey Publishing 1999
677:
451:, could occur because of poor weather during the
177:for red wine grapes, replaces the green color of
1606:
844:derived from the sugar in the grapes go through
989:
987:
985:
892:
890:
888:
886:
884:
882:
880:
878:
876:
282:starts while in much cooler climates, like the
181:as the grape berries themselves change color.
1066:
1037:Assessing Ripeness Through Sensory Evaluation
597:also rectify deficiencies in sugar levels by
1519:Effects of climate change on wine production
982:
873:
855:. Another method is through analysis of the
812:, which contributes to the floral aroma of
253:Varying ripeness levels for different wines
50:on the vine which signals the beginning of
1073:
1059:
516:. Viticulturists and winemakers can use a
722:
290:, this may not occur until 70 days after
145:Pinot noir grapes in the early stages of
1047:, information from Cooperative Extension
1041:Wine Business Monthly, November 15, 2006
975:Handbook of fruit science and technology
777:
726:
681:
640:
583:
474:
391:
388:Factors influencing when ripeness occurs
256:
140:
97:between sugar (as well as the potential
29:
665:such as the strips used for a standard
629:) and then using an indicator (such as
14:
1607:
470:
336:The presence of alcohol (particularly
208:size of grape clusters and young vine
1054:
500:is a good indicator of the amount of
853:gas chromatograph-mass spectrometers
137:What happens to a grape as it ripens
1017:In search of optimal grape maturity
24:
1123:International Grape Genome Program
25:
1636:
1103:Annual growth cycle of grapevines
1027:
608:are tartaric and malic acid with
1591:
1590:
774:Flavor precursors and glycosides
616:acids playing a small role. The
364:in its complex interaction with
123:phenolic compounds in the grapes
1080:
995:"Understanding Wine Technology"
678:Balancing sugar, acidity and pH
317:into alcohol by the process of
1007:
997:pg 18-27 DBQA Publishing 2005
965:
953:"The Oxford Companion to Wine"
708:University of California-Davis
691:notes, these numbers are the "
491:
13:
1:
1550:Glossary of viticulture terms
1182:Diurnal temperature variation
867:
808:, and include compounds such
579:
155:annual cycle of the grapevine
1560:Glossary of winemaking terms
971:D. K. Salunkhe, S. S. Kadam
34:Grapes ripening on the vine.
7:
636:
560:was used until 1961 and in
10:
1641:
1329:Integrated pest management
566:Klosterneuburger Mostwaage
540:it is measured in degrees
1588:
1542:
1524:Environmental stewardship
1499:
1405:
1362:
1280:
1237:
1167:
1088:
382:sparkling wine production
89:will continue to rise as
42:is the completion of the
1452:Great French Wine Blight
1534:Sustainable agriculture
1315:Frost damage prevention
1197:Regional climate levels
556:and most of Europe the
461:grapevine fanleaf virus
125:that contribute to the
1555:Glossary of wine terms
857:glycosyl-glucose assay
783:
732:
723:Physiological ripeness
687:
646:
589:
568:(°KMW) scale is used.
480:
398:
262:
150:
35:
979:pg 13 CRC Press, 1995
898:"From Vines to Wines"
781:
758:secondary metabolites
730:
685:
644:
594:food and wine pairing
587:
478:
434:and ailments such as
395:
260:
144:
33:
87:sugars in the grapes
1509:Adaptive management
471:Evaluating ripeness
465:plant fertilization
58:is being produced (
1427:Botrytis bunch rot
1247:Grapevine planting
1177:Climate categories
826:Cabernet Sauvignon
784:
733:
688:
647:
625:solution (such as
618:titratable acidity
590:
502:sugars in the wine
481:
399:
331:late harvest wines
296:Cabernet Sauvignon
263:
246:volatile compounds
151:
109:", as well as the
36:
1602:
1601:
1447:Grapevine yellows
951:J. Robinson (ed)
544:(symbol °Bx); in
427:canopy management
323:alcohol by volume
218:plant respiration
16:(Redirected from
1632:
1625:Wine terminology
1594:
1593:
1478:Uncinula necator
1467:Pierce's disease
1075:
1068:
1061:
1052:
1051:
1022:
1011:
1005:
991:
980:
969:
963:
949:
908:
894:
627:sodium hydroxide
522:refractive index
510:specific gravity
38:In viticulture,
21:
18:Underripe grapes
1640:
1639:
1635:
1634:
1633:
1631:
1630:
1629:
1605:
1604:
1603:
1598:
1584:
1570:Outline of wine
1538:
1529:Organic farming
1514:Biodynamic wine
1501:
1495:
1486:Red spider mite
1407:
1401:
1358:
1320:Green harvest (
1305:Erosion control
1282:
1276:
1257:Row orientation
1239:
1233:
1169:
1163:
1108:Grape varieties
1090:
1084:
1079:
1030:
1025:
1012:
1008:
992:
983:
970:
966:
950:
911:
895:
874:
870:
830:Sauvignon blanc
822:methoxypyrazine
776:
725:
714:which uses the
680:
639:
631:phenolphthalein
582:
536:, and parts of
514:distilled water
494:
473:
390:
311:sweetness level
255:
139:
28:
23:
22:
15:
12:
11:
5:
1638:
1628:
1627:
1622:
1617:
1600:
1599:
1589:
1586:
1585:
1583:
1582:
1577:
1572:
1567:
1562:
1557:
1552:
1546:
1544:
1540:
1539:
1537:
1536:
1531:
1526:
1521:
1516:
1511:
1505:
1503:
1497:
1496:
1494:
1493:
1488:
1483:
1482:
1481:
1472:Powdery mildew
1469:
1464:
1459:
1454:
1449:
1444:
1439:
1434:
1429:
1424:
1419:
1413:
1411:
1403:
1402:
1400:
1399:
1394:
1389:
1384:
1379:
1374:
1368:
1366:
1360:
1359:
1357:
1356:
1351:
1346:
1341:
1336:
1331:
1326:
1322:Vendange verte
1317:
1312:
1307:
1302:
1297:
1292:
1286:
1284:
1278:
1277:
1275:
1274:
1269:
1264:
1262:Trellis design
1259:
1254:
1249:
1243:
1241:
1235:
1234:
1232:
1231:
1230:
1229:
1224:
1219:
1209:
1204:
1199:
1194:
1189:
1184:
1179:
1173:
1171:
1165:
1164:
1162:
1161:
1158:Vitis vinifera
1154:
1147:
1142:
1137:
1125:
1120:
1115:
1110:
1105:
1100:
1094:
1092:
1086:
1085:
1078:
1077:
1070:
1063:
1055:
1049:
1048:
1042:
1029:
1028:External links
1026:
1024:
1023:
1006:
981:
964:
909:
871:
869:
866:
775:
772:
724:
721:
701:vineyard soils
679:
676:
638:
635:
599:chaptalization
581:
578:
548:it is degrees
546:Germany (wine)
493:
490:
472:
469:
440:powdery mildew
412:growing season
389:
386:
362:ageing of wine
327:residual sugar
254:
251:
190:photosynthesis
138:
135:
26:
9:
6:
4:
3:
2:
1637:
1626:
1623:
1621:
1618:
1616:
1613:
1612:
1610:
1597:
1587:
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1578:
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1556:
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1548:
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1535:
1532:
1530:
1527:
1525:
1522:
1520:
1517:
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1512:
1510:
1507:
1506:
1504:
1498:
1492:
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1398:
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1375:
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1370:
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1340:
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1335:
1332:
1330:
1327:
1325:
1323:
1318:
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1313:
1311:
1308:
1306:
1303:
1301:
1298:
1296:
1293:
1291:
1288:
1287:
1285:
1279:
1273:
1270:
1268:
1267:Vine training
1265:
1263:
1260:
1258:
1255:
1253:
1250:
1248:
1245:
1244:
1242:
1236:
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1205:
1203:
1200:
1198:
1195:
1193:
1190:
1188:
1185:
1183:
1180:
1178:
1175:
1174:
1172:
1168:Environmental
1166:
1160:
1159:
1155:
1153:
1152:
1148:
1146:
1143:
1141:
1138:
1135:
1134:
1129:
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1119:
1116:
1114:
1111:
1109:
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1087:
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1071:
1069:
1064:
1062:
1057:
1056:
1053:
1046:
1043:
1040:
1038:
1033:M. Greenspan
1032:
1031:
1020:
1018:
1010:
1004:
1003:1-891267-91-4
1000:
996:
990:
988:
986:
978:
976:
968:
962:
961:0-19-860990-6
958:
954:
948:
946:
944:
942:
940:
938:
936:
934:
932:
930:
928:
926:
924:
922:
920:
918:
916:
914:
907:
906:1-58017-105-2
903:
899:
893:
891:
889:
887:
885:
883:
881:
879:
877:
872:
865:
862:
858:
854:
849:
847:
843:
839:
835:
831:
827:
823:
819:
815:
811:
807:
801:
797:
794:
790:
789:near infrared
780:
771:
768:
767:lignification
762:
759:
755:
751:
747:
743:
739:
729:
720:
717:
713:
712:Brix:TA ratio
709:
704:
702:
698:
694:
684:
675:
672:
668:
664:
659:
657:
652:
643:
634:
632:
628:
624:
619:
615:
611:
607:
606:acids in wine
602:
600:
595:
586:
577:
574:
569:
567:
563:
559:
555:
551:
547:
543:
539:
535:
531:
530:United States
527:
523:
520:which uses a
519:
518:refractometer
515:
511:
507:
503:
499:
489:
487:
477:
468:
466:
462:
458:
454:
450:
444:
441:
437:
433:
432:vine diseases
428:
424:
419:
417:
416:tartaric acid
413:
409:
404:
394:
385:
383:
379:
375:
370:
367:
363:
359:
355:
351:
347:
343:
339:
334:
332:
328:
324:
320:
316:
312:
307:
305:
301:
297:
293:
289:
286:and parts of
285:
281:
277:
273:
269:
268:grape variety
259:
250:
247:
243:
238:
234:
230:
225:
223:
219:
215:
211:
207:
203:
199:
195:
191:
187:
186:carbohydrates
182:
180:
176:
172:
168:
164:
160:
156:
148:
143:
134:
132:
131:aroma of wine
129:, flavor and
128:
124:
120:
116:
115:physiological
112:
108:
107:total acidity
104:
100:
99:alcohol level
96:
92:
88:
84:
83:
77:
75:
71:
70:
65:
61:
57:
53:
49:
45:
41:
32:
19:
1476:
1442:Downy mildew
1386:
1354:Weed control
1344:Millerandage
1321:
1192:Microclimate
1156:
1149:
1131:
1127:
1118:Hybrid grape
1098:Ampelography
1091:horticulture
1034:
1014:
1009:
994:
972:
967:
952:
897:
850:
810:monoterpenes
802:
798:
793:spectroscopy
785:
763:
754:glycosylated
749:
741:
734:
711:
705:
689:
663:pH indicator
660:
648:
603:
591:
572:
570:
495:
482:
449:millerandage
445:
420:
400:
371:
350:wine tasting
335:
319:fermentation
308:
291:
284:Loire Valley
279:
264:
226:
183:
175:anthocyanins
170:
158:
152:
146:
80:
78:
74:dessert wine
67:
39:
37:
1620:Viticulture
1252:Propagation
1089:Biology and
1082:Viticulture
693:royal flush
667:litmus test
656:wine faults
558:Baumé scale
534:New Zealand
498:must weight
492:Must weight
410:during the
354:anaesthetic
179:chlorophyll
167:malic acids
103:must weight
91:acid levels
48:wine grapes
46:process of
1609:Categories
1580:Winemaking
1502:and issues
1500:Approaches
1462:Phylloxera
1432:Bot canker
1334:Irrigation
1310:Fertilizer
1283:management
1212:Topography
1202:Soil types
1013:L. Bisson
868:References
861:micromoles
846:hydrolysis
842:glucosides
834:glycosides
806:flavonoids
744:(from the
742:engustment
740:notion of
697:poker hand
604:The major
580:Acid level
552:(°Oe); in
526:hydrometer
486:glycosides
408:heat waves
397:resources.
304:Pinot noir
300:Chardonnay
272:California
242:Flavonoids
210:shoot tips
121:and other
93:fall. The
1491:Vine moth
1457:Nematodes
1422:Black rot
1406:Pests and
1382:Noble rot
1377:Festivals
1222:elevation
1170:variation
1140:Rootstock
621:standard
538:Australia
453:flowering
436:bunch rot
374:Champagne
346:mouthfeel
276:Australia
233:magnesium
222:potassium
169:. During
163:fruit set
64:fortified
62:, still,
60:sparkling
1615:Oenology
1596:Category
1565:Oenology
1543:See also
1437:Dead arm
1409:diseases
1387:Ripeness
1339:Klopotec
1281:Vineyard
1240:planting
1238:Vineyard
1187:Drainage
1145:Vineyard
1133:Veraison
1128:Ripening
993:D. Bird
814:Riesling
756:form as
671:pH meter
651:hydrogen
637:pH level
623:alkaline
614:succinic
573:veraison
403:Sunlight
292:veraison
280:veraison
214:dilution
202:fructose
171:veraison
159:veraison
147:veraison
82:veraison
44:ripening
40:ripeness
1397:Weather
1392:Vintage
1364:Harvest
1349:Pruning
1300:Coulure
1207:Terroir
896:J. Cox
838:enzymes
710:is the
562:Austria
550:Oechsle
506:density
423:pruning
378:vintage
338:ethanol
288:Germany
229:calcium
198:glucose
194:Sucrose
119:tannins
95:balance
52:harvest
1290:Canopy
1217:aspect
1113:Grapes
1001:
959:
904:
820:, and
818:Muscat
791:(NIR)
750:gustus
738:French
610:citric
571:After
554:France
366:esters
358:palate
352:, the
342:weight
237:sodium
1417:Birds
1272:Yield
1227:slope
1151:Vitis
748:root
746:Latin
716:ratio
457:boron
315:yeast
244:and
206:yield
127:color
105:and "
1575:Wine
1372:Brix
1295:Clos
999:ISBN
957:ISBN
902:ISBN
828:and
816:and
612:and
564:the
542:brix
438:and
425:and
344:and
302:and
274:and
235:and
200:and
69:rosé
56:wine
508:or
1611::
984:^
912:^
875:^
840:,
695:"
532:,
467:.
384:.
306:.
231:,
192:.
133:.
111:pH
85:,
72:,
66:,
1324:)
1136:)
1130:(
1074:e
1067:t
1060:v
1039:"
1035:"
1019:"
1015:"
977:"
973:"
20:)
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