Caballero B. (ed.) Encyclopaedia of Food Science, Food Technology and Nutrition. Ten-Volume Set

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depends, as for the short Charmat, on whether tar-

taric stabilization is needed. After bottling under

pressure at a low temperature, the sparkling wine is

left to age for a long period (7–14 months) in bins so

as to acquire the premium organoleptic qualities, es-

pecially with wines of Pinot origin (such as the

German dry sparkling wines). A typical example of

this type of production is the German and Austrian

natural sparkling wine known as Sekt. Even though

this sparkling wine can be produced following the

traditional method, Charmat method, or Transfer

method, for the most part, the wine is produced

using the long Charmat method (85%), only 7% by

the transfer method, and 8% by the traditional

method.

0016 In some cellars, once fermentation is complete,

yeast autolysis is accelerated by increasing the tem-

perature in the Charmat tank to 42



C for 72 h. The

disadvantage is that the CO

pressure is doubled from

5 bar at 20



C to 10 bar. Therefore, Charmat tanks

resistant to 13 bar are used, even though the pressure

in the interior is not allowed to exceed 8–9 bar be-

cause decompression is provoked. The temperature

stimulates the activity of the proteolytic enzymes and

the lysis phenomenon to improve similar organoleptic

characteristics to those of sparkling wines fermented

in the bottle. This shortens the long Charmat method,

even though an aging period of several months is still

recommended after bottling.

Transfer Method

0017 This system, of Italian origin, obviates the need

for the riddling and disgorging steps characteristic

of the Champenoise, traditional, or classical methods.

The term ‘transfer’ refers to transferring the wine,

which has undergone a second fermentation in a

bottle to a Charmat tank (Figure 1). Therefore, it

can be considered an intermediate system between

the Champenoise method and the Charmat method.

The wine is left in the bottle with only a crown cap

during a minimum of 9 months, sometimes more. It is

then transferred under pressure with the lees to the

Charmat tank. From this moment on, the process is

exactly like that of the Charmat method. The draw-

back of this method is that it is as laborious as (if not

more so) the Champenoise method (from bottle to

tank to bottle), and that filtration is carried out on a

product that contains a Champenoise bouquet, sig-

nificantly reducing the sensorial qualities of the

sparkling wine. This method is declining and has

already been abandoned in Italy, but is still employed

on a limited scale in some German, Austrian, Greek,

Hungarian, American, and Argentinean companies.

In the USA when the sparkling wine has been

transferred to another bottle different to that used

for fermentation, the label may mention that it has

been ‘fermented in bottle,’ but not ‘fermented in this

bottle,’ as in the case of sparkling wines produced by

the method champenoise.

Further Reading

De Rosa T (1987) Tecnologia dei vini spumanti. Brescia:

Edizioni AEB.

Flanzy C (1999) Oenologie: Fondements scientifiques et

technologiques. Paris: Technique et Documentation.

Naudin C and Flavigny L (eds) (1999) Larousse des Vins.

Tous les Vins du Monde (1998) Paris: Larousse-Bordas.

Rankine B (1995) Making Good Wine. A Manual of Wine-

making Practice for Australia and New Zealand.

Sydney: Pan Macmillan Australia.

Ribe

rau-Gayon P, Glories Y, Maujean A and Dubourdieu D

(1998) Traite

d’Oenologie. Paris: Dunod.

Stevenson T (1998) Christie’s World Encyclopedia of

Champagne & Sparkling Wine. Bath, UK: Absolute

Press.

Wiesenthal M and Torres MA (eds) (1988) Enciclopedia del

vino: Enologı

a, viticultura y cata. Barcelona: Ediciones

Orbis.

http://www.astidocg.it

http://www.champagne.fr

http://www.crcava.es

http://www. englishbubbly.com/html

http://www. europa.eu.int/eur-lex

http://www.talento.it

Dietary Importance

S S Percival and S L Talcott, University of Florida,

Gainesville, FL, USA

Background

0001The health benefits ascribed to wine are associated

with both moderate alcohol intake and the content of

polyphenols that have antioxidant capability. This

review will cover wine composition, epidemiological

data, and experimental data related to beneficial

effects of wine consumption. It is important to note

that alcohol consumption and mortality follow a

J-shaped curve (Figure 1); that is, if nondrinkers are

assigned a relative risk of 1.0, then the odds ratio for

relative risk of adverse health effects is lower for those

WINES/Dietary Importance 6209

consuming one to three drinks per day. When con-

sumption is greater than three drinks per day, the

odds ratio is greater than for nondrinkers. Thus, tee-

totalers and heavy drinkers have a greater risk of

adverse effects and death than moderate consumers.

Health benefits, accordingly, are manifested only in

relation to a moderate consumption of wine, moder-

ate in terms of quantity related to body size and

therefore defined as two glasses (150 ml per glass or

5 oz per glass).

0002 The grape species used in wine production is usu-

ally Vitis vinifera. When information is available, we

will also include data related to the species Vitis

rotundifolia, also known as the muscadine grape.

This grape has a higher antioxidant profile and con-

tains unique components and amounts compared

with Vitis vinifera. Very few studies have been done

with the Vitis labrusca, which is also known as the

Concord grape.

Wine Composition

0003 The phytochemical content of grapes of all species is

linked to environmental conditions, but levels in

wines are also influenced by viticultural practices,

variety, and processing procedures (Table 1). In

addition to ethanol, wine (especially red wine) con-

tains a range of phytochemical compounds that

confer health benefits for a variety of reasons that

will be discussed. These include phenolic acids

(p-coumaric, cinnamic, caffeic, gentisic, ferulic, and

vanillic acids), trihydroxy stilbenes (resveratrol and

polydatin), and flavonoids (anthocyanins, catechin,

epicatechin, myricetin, kaempferol, and quercetin).

An estimate of the different classes of compounds in

wine follows (Table 2). Nonflavonoid compounds

such as the hydroxy benzoic acids, hydroxycinnamic

acids and stilbenes make up about 40% of the total

phenolic acids and polyphenols. Flavonoids make up

the remaining 60%. Hydroxybenzoic acids make

up about 60% of the nonflavonoid fraction with

gallic acid, about 120 mg l

1

, found in the highest

quantity. Anthocyanins make up the largest portion

of the flavonoids with the distribution as 50% antho-

cyanins, 30% flavanols such as catechin and epicate-

chin and 20% flavonols such as quercetin, myricetin,

and kaempferol. Procyanidins are large complexes of

epicatechin, catechin, and gallic acid. They comprise

the largest fraction of the flavanols. A high level of

flavonoids is found in the skin and seeds of the grape.

Therefore, the longer the fermentation time with skin

and seeds, the more flavonoids are extracted. Conse-

quently, white wine has relatively low levels of flavo-

noids compared with red (Table 2).

0004V. rotundifolia, the muscadine, has approximately

twice the polyphenolic content of the more com-

monly consumed V. vinifera and significantly more

gallic acid and epicatechin (Table 3). V. rotundifolia

has less catechin and procyanidin B3 than V. vinifera.

Also, V. rotundifolia is found to have approximately

10 times more resveratrol than V. vinifera.

0005Muscadine grapes are similar to V. vinifera in that

both contain high concentrations of neutral and

acidic polyphenolic compounds. Neutral phenolics

contain characteristic structural features that have

been associated with radical scavenging abilities,

including the number and location of hydroxyl

groups, and the presence of a 2, 3 double bond.

Additionally, these compounds have the ability to

act synergistically with other antioxidant compounds

or chelate metals that participate in free radical

generation.

Epidemiological Evidence for Health

Benefits of Red Wine

0006Epidemiological evidence that led to the suggestion

that red wine confers benefits was first revealed in the

Mediterranean population. Despite an intake of sat-

urated fat about three times greater than Americans,

the French population has only about one-third of the

incidence of coronary disease. Consumption of red

wine has been hypothesized to be the contributing

factor in protection against cardiovascular disease

1800

1600

1400

1200

1000

800

600

200

400

01 2 345 67

Drinks per day

Men

Women

Deaths per 100 000

fig0001 Figure 1 Rates of death from all causes.

tbl0001Table 1 Variability in total phenolics analyzed by different

laboratories

Investigator 1 Investigator 2 Investigator 3

Cabernet Sauvignon 1800 2600 821

Petite Syrah 3200 2266

Muscadine 1269

6210 WINES/Dietary Importance

and is popularly known as the ‘French Paradox.’

The positive attributes of the Mediterranean diet,

besides a moderate consumption of alcohol, mainly

as wine, include: high monounsaturated to saturated

fat ratio; high consumption of vegetables, fruits,

legumes, and grains; moderate consumption of

dairy, mostly as cheese; and low consumption of

meat. The French population consumes less milk,

and more garlic, cheese, fruits, vegetables, and wine.

Therefore, this postulate, that red wine is the pro-

tective factor in these diets, cannot be wholly ascribed

to the wine. Other dietary factors may play a con-

siderable role.

0007 Epidemiological data showing a relationship be-

tween chronic disease and red wine consumption are

limited, but the data suggest a significant correlation

between red wine and reducing the risk of heart dis-

ease. The fact that red wine is high in flavonoids and

polyphenols and therefore antioxidants is often the

reason why the consumption of red wine is thought to

reduce the risk of disease.

0008 Although benefits due to red wine consumption

and heart disease are largely thought to be due

to polyphenols, some studies suggest a benefit due

to alcohol regardless of the form in which it was

consumed. One study was not successful in showing

a wine and heart disease correlation, but the

consumption of wine by this particular population

was very low.

0009Epidemiological evidence supporting a reduction in

risk for certain cancers is strong for consumption of

fruits and vegetables or for the consumption of green

tea, yet data do not exist for red wine consumption.

Some evidence exists from animal studies and will be

discussed.

Relation to Diet

Bioavailability

0046Research on the absorption of polyphenolics from

foods is limited, and yet it is the critical element

in understanding health benefits conferred by red

wine as well as by fruits, vegetables, and teas. Limited

data are available on the bioavailability of bioactive

compounds from red wine; however, anthocyanins

have been detected in human plasma as well as in

the urine of volunteers who drank red wine. Further-

more, anthocyanins have been detected in human and

rat plasma as intact glycosides with no deglycosyla-

tion or further methylation or sulfation, although the

level was less than 1% of the oral dose. A methylated

form of a particular anthocyanin was detected in the

liver of the animals. Catechin has been detected in

tbl0002 Table 2 Relative distribution of phenols and polyphenols in red and white wines

Red wine White wine

Total polyphenols and phenolic acids 1200 mg l

1

200 mg l

1

Nonflavonoids 240–500 mg l

1

60% 160–260 mg l

1

85%

OH-benzoic acids (gallic acid, protocatechuric acid, p-hydroxybenzoic acid) 15% 45%

OH-cinnamic acids (coutaric, caffeic, caftaric, coumaric, ferulic) 80% 55%

Stilbenes (resveratrol, polydatin) 5% trace

Flavonoids 750–1060 mg l

1

40% 25–30 mg l

1

15%

Flavonols (quercetin, myricetin, kaempferol, rutin) 10% 0

Flavanols (catechin, epicatechin, procyanidins) 30% 100%

Anthocyanins (delphinidin, cyanidin, petunidin, peonidin, malvidin) 60% 0

tbl0003 Table 3 Comparison of polyphenolics in Muscadine and Cabernet Sauvignon

Compounds Cabernet Sauvignon13 -day skin fermentation Muscadine, cv. Noble 14 -day skin fermentation

Total phenolics 821 mg per liter of GAE

1269 mg per liter of GAE

Gallic acid 15.9 200

Caftaric 4.6 0.9

Coutaric 0 0.3

Catechin 32.6 2.6

Ellagic 0 4.1

Epicatechin 40.3 205

Procyanidin B3 30.2 0.9

Procyanidin B4 5.2

Total added 128.8 (15.7% of GAE) 413.8 (32.6%)

GAE, gallic acid equivalents.

WINES/Dietary Importance 6211

mouse plasma after consumption of a diet containing

wine solids.

0011 Colonic bacteria can metabolize polymeric procya-

nidins. An in vitro study showed that they were able

to be completely degraded to low-molecular-weight

aromatic compounds. These monomers may be easily

absorbed in the large intestine and may therefore

result in further beneficial effects.

0046 Numerous studies indirectly assess bioavailability

by measuring plasma antioxidant levels as an index

of absorption and transport to the blood. Each day,

356 ml (12 oz) of red Muscadine wine (cv. Noble)

were consumed for 4 days. The oxygen radical ab-

sorptive capacity (ORAC) in human plasma was in-

creased by 10–15% (Figure 2). When the serum

sample was deproteinized by acetone, the plasma

ORAC values were lower but increased 21–33%

over the 4 days. Mice consumed muscadine wine

or Cabernet Sauvignon over 9 days as their sole

source of fluid. Based on preconsumption levels,

plasma ORAC levels rose by two-thirds in the case

of the cabernet and doubled in the case of the musca-

dine (Figure 3). The results showed that the antioxi-

dant capacity in plasma increased two- to three-fold

with the consumption of the wines. The antioxidant

capacity in this study was measured by DPPH (1,

1-diphenyl-2-picrylhydrazyl). This has been shown

by others and confirms that the compounds that con-

fer antioxidant activity are absorbed and transported

to the plasma.

Intake

0012 The estimated intake of total polyphenols in the diet

per day is 1 g. Although this value was derived over

25 years ago, it appears still to hold true. Wine com-

position is complex and variable. Because of the vari-

ability among grapes and wine, it would be difficult

to estimate the consumption of polyphenols, even if

consumption of the wine volumes were known. Teis-

sedre, however, calculates the flavonoid consumption

by the French population to be about 400 mg per day

from red wine. In the USA, the consumption would

probably be less.

Individual Components of Red Wine having

Potential Benefits

0013 The phenolic compounds in wine all have the poten-

tial to act as antioxidants. Because of structural dif-

ferences, the phenolics vary in their relative activity.

0014 Ellagic acid has been well studied as an isolated

compound. Ellagic acid is an important phenolic

compound found in many small fruits including

cranberry, blackberry, blackcurrant, mayhaw, straw-

berry, and raspberry. Various reports have shown a

positive effect for ellagic acid as a functional anti-

mutagen, anticarcinogen, and inhibitor of various

chemically induced cancers. Muscadine grapes have

appreciable amounts of ellagic acid (10–25 mg l

1

)

thought to be derived either directly from hydrolysis

of ellagitannins or from dimerization of gallic acid.

0015Resveratrol is a phytoalexin that has been associ-

ated with anticancer, antiinflammatory, and antimu-

tagenic activity. Resveratrol is found in the highest

concentration in the skin and seeds, especially when

the plant has been stressed. The content of resveratrol

in the red wines from V. vinifera contains very little

resveratrol, whereas it is found in higher concentra-

tions in the muscadine wines. During processing, the

longer the skins and seeds are fermented with the

crushed grapes, the more resveratrol will be found

in the wine. Resveratrol was first discovered in the

V. vinifera grape species. It is synthesized by the leaf

and skin in response to fungal infection. Thus, wine

ORAC

Water

Cabernet

Muscadine

Day 1 Day 4 Day 9

fig0003Figure 3 Mouse serum oxygen radical absorptive capacity

(ORAC) values after 9 days of consumption.

1234

Day of consumption

Run #1, whole serum

Run #2, whole serum

Run #1, deproteinized serum

Run #2, deproteinized serum

ORAC

fig0002Figure 2 Human serum of oxygen radical absorptive capacity

(ORAC) values after 9 days of consumption.

6212 WINES/Dietary Importance

derived from healthy plants has little to no resvera-

trol. Muscadine, however, has higher levels of resver-

atrol. The biological activities of resveratrol are

numerous. It has been shown that resveratrol has

antiinflammatory activity from its ability to inhibit

eicosanoid production, antioxidant activity by scav-

enging radicals and chelating metals, and anticancer

activity including antimutagenic, anticarcinogenic,

and chemopreventative activity. Heart health benefits

may be derived from its ability to inhibit platelet

aggregation and induce vasorelaxation. Resveratrol

has also been shown to have estrogenic activity.

0016 Catechin and epicatechin are major components in

red wine and are responsible for all the flavonoid

content of white wine. These polyphenols are high-

molecular-weight molecules with the ability to com-

plex with other phenolic acids making a near endless

array of procyanidins. They are also found in green

tea and chocolate.

Health Benefits

Alcohol, Flavonoids, and Immunity

0017 Ethanol is known to modify immune cell function

detrimentally. In animals that drank 5% ethanol

daily, there was a marked reduction in total spleno-

cytes and total thymocytes, and an increase in T-cells

relative to B-cells in the periphery. An increase in

natural killer (NK) cytotoxic activity in both the

spleen and the periphery was also found, but there

was little change in NK cell number. We also found a

modest, but significant, change in peripheral NK cell

numbers.

0018 Alcohol consumption for 2, 4, and 8 weeks was

associated with a decrease in the number of NK cells

in the spleen and periphery over time. The cytotoxic

activity of peripheral and splenic NK cells was

decreased modestly, in contrast to the aforemen-

tioned study.

0019 The effect of alcohol on NK activity is one of the

most controversial because of the variable results

among laboratories. A reduction in the number of

NK cells or their activity would have serious con-

sequences in terms of host defense to viruses and

tumors. Further research is needed to understand the

role of both alcohol and wine polyphenolics on NK

cell activity.

0020 The detrimental effect of alcohol on immune func-

tion is thought to be due to free radical generation

related to acetaldehyde. By extension, then, will the

consumption of red wine reduce the detrimental

effects of alcohol on immunity by virtue of its anti-

oxidant polyphenolics? Consider, first, the data that

show an effect of polyphenols on the modification of

immune cell function. Although the studies showing

modification of immune cell function have been

largely done with isolated compounds, the research

suggests that flavonoids can alter immunity.

0021Flavonoids have been studied in relation to NK

cell function. A dose-dependent antitumor activity

against solid tumors was exhibited using a type of

flavone in mice. This was attributed to a stimulation

of cytokine gene expression caused by the flavone.

Specifically, mRNA for interferon a was upregulated.

This was an ex vivo experiment, so it is not known if

naturally occurring flavones show the same effect or

if the food itself is potent enough to alter cytokine

expression.

0022Flavonoids commonly found in red wine have been

shown to be antiallergenic. Certain flavonoids were

found to inhibit the stimulated release of mast cell,

eosinophil, and basophil granular components, with

quercetin being particularly active. Antiviral activity

was demonstrated by the inhibition of viral infection

of cells and inhibition of the replication of virus, once

the cell was infected. Different flavonoids have differ-

ent capabilities. Antiinflammatory activity was dem-

onstrated by the inhibition of neutrophil activation

via inhibition of the NADPH oxidase activity. Inhib-

ition of phospholipase A

was also demonstrated,

resulting in an inhibition of the release of arachidonic

acid and reduced production of prostaglandins and

leukotrienes. These activities have not been demon-

strated in studies utilizing the wine itself.

0023A study was conducted in 4-week-old mice in

which they consumed one of four beverages put into

their drinking bottles as the only fluid available to

them. They drank a Muscadine wine, a Cabernet

Sauvignon wine, ethanol, or water for 8 weeks. The

Muscadine, Cabernet, and ethanol were adjusted to

6% alcohol, and it was shown that the mice drank an

equal volume of fluid without any differences in body

weight or food consumption among the groups. The

amount of wine or ethanol consumed by the mice was

equivalent to two 178-ml (6-oz) glasses of wine for a

human when based upon caloric consumption. This

model utilized a moderate consumption of the food

itself rather than isolated compounds or pharmaco-

logical doses.

0024Some aspects of immune function were impaired in

the mice that consumed ethanol, but not in those that

consumed wine. Ethanol consumption decreased the

basal numbers of NK cells and T-lymphocytes. How-

ever, the mice that consumed the same amount of

ethanol as wine had basal levels of NK cells and

T-lymphocytes equal to the water-consuming controls.

0025Mice were stimulated with a low level of lipopoly-

saccharide (LPS) in order to induce an immune

response. We asked, first, if ethanol would reduce

WINES/Dietary Importance 6213

the response and, second, if the red wine would pre-

vent the reduced response. In control mice, 24 h after

injection of LPS, blood lymphocyte numbers were

reduced due to emigration and turnover. However,

in the mice that consumed ethanol, the T-lymphocyte

numbers were the same before and after the LPS.

The mice that consumed either of the red wines

showed a normal emigration of T-lymphocytes after

LPS injection.

0047 NK cell numbers, however, increase after LPS,

likely due to the reduced numbers of other lympho-

cytes from the blood and/or possibly due to the mi-

gration of NK cells from the bone marrow. The mice

that consumed ethanol had the lowest increase in NK

cell numbers, whereas the mice consuming the red

wine had an increase equal to that of the animals

that drank water. These data suggest an impaired

immune response to the LPS when even a moderate

amount of ethanol was consumed. The mice that

consumed wine as their sole beverage responded

identically to the mice that consumed water. Perhaps

free radicals generated during alcohol metabolism

damaged the immune response, but the polyphenolic

compounds in the red wine prevented the damage. It

was also hypothesized that another mechanism could

be functioning, i.e., the alteration in the phase I and

phase II enzymes involved in alcohol degradation.

0026 Free radical damage due to ethanol consumption

was not found in any of these groups. Liver and

lymphocyte glutathione levels and thio barbituric

acid-reacting substances (TBARS) were not signifi-

cantly different among the groups, stimulated or non-

stimulated. The data suggest that immunity can be

compromised without any overt signs of free radical

damage.

Cardiovascular Disease

0027 The health benefits of red wine related to cardio-

vascular disease have been documented in epidemi-

ological studies, as well as experimental animals and

humans. An excellent review of this was presented

by German and Walzem in the Annual Reviews of

Nutrition (2000).

0028 Research has shown that moderate alcohol intake,

regardless of the type of beverage, lowers cardiovas-

cular mortality risk. The mechanism is related to the

elevations in high-density lipoprotein (HDL) choles-

terol. The rise in HDL cholesterol accounts for nearly

half of the reduction in risk for death due to heart

disease. Ethanol also stimulates liver lipogenesis,

resulting in increased plasma triglycerides, increased

lipoprotein lipase, thereby increasing triglyceride-rich

lipoproteins, and increased expression of ApoAI and

ApoAII, which together have a net effect of increasing

the production of HDL.

0029The other nonalcoholic components of wine have

also been shown to modify physiological cardio-

vascular health. One of the initial factors related to

plaque formation in heart disease is the oxidation of

low-density lipoprotein (LDL). Once oxidized, the

molecule is rapidly taken up by macrophages that

then take on the appearance of ‘foam cells.’ These

foam cells modify the endothelium and contribute to

the formation of blockage. Many ex vivo studies have

measured the oxidation rates of LDL in the presence

of wine phenolics and shown it to be reduced. It is

not clear how much or to what extent the LDL is

protected in vivo.

0030In addition to the protection against LDL oxida-

tion, the polyphenols and phenolic acids in wines

affect endothelial cells, platelets, lymphocytes, and

macrophages through changes in cell signaling. The

phenolic compounds in wine, as well as the ethanol,

have been shown to reduce platelet aggregation. In

addition, phenolics and ethanol have both been

shown to improve endothelial function, as measured

by vasodilation, vasorelaxation, or cellular adhesion

molecule expression. Again, the extent to which this

happens in vivo is not known.

Cancer

0031One of the few studies that used wine itself in the

experimental design showed a reduction in cancer

frequency. Mice consumed commercial wines or 12%

ethanol with or without ethyl carbamate at 10 or

20 mg per kilogram of body weight for 41 weeks.

Liver and lung were examined, and the incidence of

tumors (percentage of mice with tumors) and the fre-

quency (number of tumors per tumor-bearing mouse)

were evaluated. Although the incidence of liver

tumors was not consistently affected by the treat-

ments, the frequency of tumors was significantly less

for the wine-drinking animals than for the water- or

ethanol-drinking animals. Similar results were found

for the incidence and frequency of lung adenomas.

0032Moderate wine consumption in humans was asso-

ciated with protection against hydrogen peroxide-

induced DNA damage, a preliminary event related

to cancer. Four volunteers drank 300 ml (9 oz) of

red or white wine. Blood samples were collected

before drinking and 1, 3, 8, and 24 h after drinking.

Hydrogen peroxide-induced micronucleated cell

frequency was determined in fresh lymphocytes that

were incubated in the donor’s homologous serum.

Less damage occurred when the lymphocytes were

incubated with their respective plasma 1 h after con-

sumption, but not before consumption or at 8 or 24 h,

suggesting that the protective effects are transient due

to turnover of the bioactive compounds.

6214 WINES/Dietary Importance

0033 HTLV-1 transgenic mice that develop clinical and

pathological features resembling human neurofibro-

matoses were fed dehydrated and dealcoholized wine

(wine solids). The wine solids diet contained 0.04%

polyphenols. Mice were examined daily for tumors,

and the endpoint was age of tumor onset (latency).

The age at which the first tumor appeared in the

control mice and that in the experimental mice

were 71 + 4 days and 102 + 10 days, respectively in

the first experiment and 63 + 4and86+ 6daysin

the second. They calculated the wine solid concen-

tration at approximately one-quarter of that of a

human consumption of 1 g of polyphenols per day.

Catechin was the major polyphenol measured in the

wine.

Other Diseases

0034 Many other chronic diseases exist that are thought to

be due to free radical damage. For example, Parkin-

son’s and Alzheimer’s diseases, diabetes, arthritis,

inflammatory disorders, radiation injury, reperfusion

injury, and macular degeneration as a few examples

are thought to result from the accumulated damage

caused by free radicals. No data exist to suggest that

red wine consumption will prevent or alter the course

of these diseases.

Mechanisms

Antioxidation

0035 The mechanisms by which the compounds in red

wines are thought to provide benefits related to risk

reduction of chronic disease are via the antioxidant

capabilities of the polyphenolic compounds. In gen-

eral, antioxidants work by different mechanisms.

Firstly, a free radical is defined as a compound miss-

ing an electron. Polyphenols, and antioxidants in

general, can donate electrons to the free radical to

prevent the free radical from obtaining electrons from

the lipids of cell membranes, proteins, or nucleic

acids. Secondly, the phenolics in red wine, shown by

in vitro studies, can chelate metals, particularly iron

and copper, which participate in the generation of

free radicals. Thirdly, the phenolics in red wine

can spare or help in the regeneration of other

antioxidants. Flavonoids have been shown to con-

serve endogenous vitamin E contained in the LDL

molecule.

0036 The relative strengths of the flavonoids in their

ability to prevent free radical damage by any of the

above mechanisms is dependent upon the system used

to study it. Numerous systems exist, in both aqueous

and hydrophobic phases. The radical generated in the

procedure as well as the detection system are different

and can result in different effects. Some generaliza-

tions of structural requirements can be drawn to

signify relative strengths of the polyphenols. Conju-

gation between the A and B rings in the form of a 2,3

double bond, a 3

di-hydroxyl configuration of the

B ring, a 3-hydroxyl group in the C ring, and a 5-

hydroxyl group in the A ring is highly significant for

the radical scavenging function. Glycosylation of the

polyphenols as well as sulfation and methylation may

result in changes to the relative antioxidant strength.

As stated earlier, the absorption and relative bioavail-

ability are factors in assessing relative antioxidant

strength. Much is yet to be done to understand the

structure–function relationship of the thousands of

polyphenolic compounds. Although the mechanisms,

components, and availability are not yet clear,

consumption of red wine is known to increase the

antioxidant capacity of the plasma.

Cell Signaling

0037Flavonoids and therefore, by extrapolation, bio-

active red wine components produce other metabolic

changes that could be interpreted as beneficial. Com-

ponents found in red wine are known to inhibit the

arachidonic acid cascade via inhibition of phospho-

lipase A2, lipoxygenase, and cyclooxygenase, thus

accounting for potential antiinflammatory activity.

Growth inhibitory activity via, for example, p53,

tyrosine kinase, or polyamine metabolism have been

shown to result from bioactive compounds found in

red wine. Very little work has been done in vivo or

with the wine itself.

Microsomal Detoxification Enzymes

0038Changes in the levels of Phase I and Phase II micro-

somal detoxification enzymes are associated with

both beneficial and harmful effects. Inhibition of the

Phase I microsomal detoxification enzymes is associ-

ated with drug toxicity due to a reduction in drug

metabolism. Activation of the phase I enzymes is

associated with drug tolerance or the conversion

of innocuous compounds to toxic or carcinogenic

compounds. Induction of phase I enzymes has been

associated with the promotion stage of carcinogen-

esis. Potential phase I enzymes that may be involved

in carcinogenesis include cytochrome P450 2E1

(CYP2E1), CYP1A1, CYP1A2, and CYP3A4.

Alcohol is known to induce CYP2E1.

0039Induction of phase II enzymes is associated with

anti-initiation processes related to cancer. Enzymes

such as glutathione S-transferase (GST), epoxide

hydrolase, N-acetyltransferase, and quinone reduc-

tase have been linked to beneficial anticancer

activities.

WINES/Dietary Importance 6215

0040 Different dietary agents result in distinct alter-

ations in the expression in phase I and II enzymes.

For example, butylated hydroxy toluene (BHT),

ethoxyquin, indol-3-carbinol, and phenethyl isothio-

cyanate induced both the phase I and the phase II

isozymes and are therefore referred to as bifunctional

agents. Caffeic acid, garlic oil, and propyl gallate

induced phase II enzymes, but not phase I. 4-Methyl

catechol, a-tocopheral, and red wine decreased phase

I and induced GST. The type of red wine used in this

study was not defined. The ratio of the phase I/phase

II is more important in understanding protection or

toxicity as opposed to the levels of one or the other. If

the relative increase in phase II enzymes is greater

than the phase I enzymes, then the assumption is

that it is overall protective. If phase I enzymes in-

crease relatively greater than phase II, then the poten-

tial for damage, by free radicals or production of

toxic compounds, is greater. Alcohol consumption is

known to induce phase I CYP2E1, resulting in pro-

duction of acetaldehyde. Acetaldehyde, whether

generated by this mechanism or by alcohol dehydro-

genase, is potentially damaging due to its participa-

tion in free radical generation.

0041 In one of the few articles that used the wine itself,

Chan et al. showed that red wine solids, but not white

wine solids, inhibited CYP3A4. In the study by Perci-

val and Sims, liver microsomal cytochrome CYP2E1

and GST were altered by wine consumption, and

Muscadine wine resulted in different patterns relative

to the Cabernet Sauvignon. The Muscadine wine

reduced CYP2E1 about 80%, whereas the Cabernet

had no effect. Although the GST activity was also

reduced in the mice that drank Muscadine, the ratio

between the two enzymes was increased threefold,

suggesting a beneficial effect of the Muscadine wine.

GST activity was no different in the ethanol group

or the Cabernet group compared with the water-

consuming group, suggesting that there are unique

components in the Muscadine wine that resulted in

the observed changes. Moreover, the mice that drank

the Cabernet Sauvignon did not have an extensive

change in the microsomal detoxification enzymes,

signifying a unique response of the mice to the

Muscadine wine.

0042 Ellagic acid has been shown to increase phase II

enzymes GST and quinone reductase in mice. It has

also been shown to inhibit metabolic activation of

carcinogens. For example, ellagic acid inhibits the

conversion of polycylic aromatic hydrocarbons,

nitroso compounds, and aflatoxin B1 into com-

pounds that cause genetic damage. Ellagic acid was

also shown to inhibit CYP1A1. The anticarcinogenic

effectiveness of ellagic acid was due to several

different structural aspects of the molecule.

Summary

0043Red wine consumption results in an increase in anti-

oxidant levels in the blood. Data on benefits of the

individual compounds are emerging, but the study

of red wine itself is limited. Health benefits can be

demonstrated in epidemiological and animal studies

regarding heart disease, but information is less solid

regarding cancer, and nonexistent for other disease.

The data cannot be ascribed solely to the phytochem-

ical content of the wine since moderate alcohol intake

is known to have benefits, both physiologically and

psychologically.

0044The mechanisms by which the phenolic/poly-

phenolic compounds confer benefits are via their

antioxidant activity, intracellular signal modification,

alterations in gene expression, and alterations in

microsomal detoxification enzyme activity. Other

functional modifications that occur due to pheno-

lics/polyphenolics, such as antimutagenic, anticarci-

nogenic, or antiinflammatory activity are derived

from one of these major mechanisms.

0045The contribution of red wine to health can only be

understood in the context of the whole diet. In popu-

lations that consume limited amounts of fruits and

vegetables, as in Denmark, the consumption of wine

is likely a significant contributing factor of phenolics

and other phytochemicals and therefore more likely

to provide benefits. In other populations, such as

those that consume a Mediterranean-style diet, red

wine is less likely to contribute to the overall health

and disease risk reduction due to the consumption of

olive oil, fruits, and vegetables. Recommendations to

consume red wine for its beneficial effects may be

imprudent, due to the health problems associated

with overuse. However, if a person drinks alcohol

sensibly, red wine has an advantage due to its contents

of beneficial compounds.

See also: Antioxidants: Role of Antioxidant Nutrients in

Defense Systems; Bioavailability of Nutrients; Cancer:

Epidemiology; Coronary Heart Disease: Etiology and

Risk Factor; Immunology of Food; Phenolic

Compounds; Tannins and Polyphenols

Further Reading

Auw J, Blanco V, O’Keefe S and Sims CA (1996) Effect of

processing on the phenolics and color of Cabernet

Sauvignon, Chambourcin, and Noble wines and juices.

American Journal of Enology and Viticulture 47:

279–286.

Bravo L (1998) Polyphenols: chemistry, dietary sources,

metabolism, and nutritional significance. Nutrition

Reviews 56: 317–333.

6216 WINES/Dietary Importance

Cao G, Sofic E and Prior RL (1997) Antioxidant and proox-

idant behavior of flavonoids: structure–activity relation-

ships. Free Radical Biology and Medicine 22: 749–760.

Clifford AJ, Ebeler SE, Ebeler JD et al. (1996) Delayed

tumor onset in transgenic mice fed an amino acid-

based diet supplemented with red wine solids. American

Journal of Clinical Nutrition 64: 748–756.

Fremont L (2000) Biological effects of resveratrol. Life

Sciences 66: 663–673.

German JB and Walzem RL (2000) The health benefits of

wine. In: McCormick DB, Bier DM and Cousins RJ (eds)

Annual Reviews of Nutrition, pp. 561–593. Palo Alto,

CA: Annual Reviews.

Manthey JA and Buslig BS (1998) Advances in Experimen-

tal Medicine and Biology. New York: Plenum Press.

Middleton E and Kandaswami C (2000) Plant flavonoid

modulation of immune and inflammatory cell functions.

In: Klurfeld DM (ed.) Nutrition and Immunity , vol. 8,

pp. 239–266. New York: Plenum Press.

Percival SS and Sims CA (2000) Wine modifies the effects of

alcohol on immune cells of mice. Journal of Nutrition

130: 1091–1094.

Rice-Evans CA, Miller N, Bolwell P, Bramley P and Pridhan

J (1995) The relative antioxidant activites of plant

derived polyphenolic flavonoids. Free Radical Research

22: 375–383.

Stoewsand GS, Anderson JL and Munson L (1991) Inhib-

ition by wine of tumorigenesis induced by ethyl carba-

mate (urethane) in mice. Food and Chemical Toxicology

29: 291–295.

Teissedre P and Landrault N (2000) Wine phenolics: con-

tribution to dietary intake and bioavailability. Food

Research International 33: 461–467.

Wine Tasting

A C Noble, University of California, Davis, CA, USA

Introduction

0001 The phrase ‘wine tasting’ is most frequently associ-

ated with subjective determination of quality of wine

by experts at competitions or wine fairs. Increasingly

often, consumers are learning about wine through

tastings conducted by wine societies; similarly, wine

bars offer the opportunity to taste single glasses

of wines. Although wines are informally ‘tasted’

throughout all phases of wine-making, for example

during aging in oak barrels, analytical sensory

methods must be used to determine if wines differ in

flavor or to measure the effects of a specific treat-

ment. In this article, standardized wine terminology

and objective sensory methods for evaluating wine

flavor will be introduced and contrasted with more

subjective quality evaluations. (See Sensory Evalu-

ation: Sensory Characteristics of Human Foods.)

Quality Evaluation

0002Assessment of quality is made as a composite re-

sponse to the sensory properties of wine based on

expectations for a given wine type. These expect-

ations are a function of previous experience with

wines. Thus, while quality judgments are required

for wine shows, for example, they are subjective.

Responses vary among individuals because of differ-

ent expectations and preferences. Therefore, the most

experienced, skilled, and sensitive of wine judges will

have differences of opinion about wine quality. Con-

siderable experience with wines is required to make

meaningful wine-quality evaluations; nearly all qual-

ity scorecards or schemes for awarding medals at

competitions assume that the judges have a concept

of the ‘standard’ for each wine type being judged. (See

Sensory Evaluation: Practical Considerations; Food

Acceptability and Sensory Evaluation.)

0003One of the most widely used scorecards is the Davis

20-point system (Table 1). For both systems, each

factor is assessed separately and judged relative to

an existing internal standard for the class of wine

being evaluated. For example, for a young white

Riesling, points are subtracted for a dark gold color

which suggests excessive oxidation in this generally

very light-colored variety, whereas a dark gold in an

older white Riesling may be consistent with a wine of

that age, so no points are subtracted.

0004These types of scorecard serve as a training device

by forcing judges to examine the same factors, but

experienced judges seldom rate each category inde-

pendently, using the specific weighting assignments.

Instead, the attributes are confounded; dark color in a

young white Riesling influences the judge to look for

and generally subtract points for an oxidized aroma

and flavor by mouth. Most experienced assessors tend

to evaluate color, aroma, taste, and flavor by mouth

and come up with a final score using their own criteria.

Further, differences in preferences result in greatly

differing overall quality evaluations. Judges who like

varietally distinct Sauvignon blanc or Cabernet Sauvi-

gnon wines (e.g., wines with intense asparagus or bell-

pepper aromas) give high-quality ratings for these

wines, whereas judges who dislike the intensely vege-

tative aromas rate the wines as being defective.

(See Sensory Evaluation: Appearance; Aroma; Taste.)

Wine Terminology

0005An alternative and more analytical approach to

wine tasting is descriptive analysis. This can be done

WINES/Wine Tasting 6217

informally by recording specific terms to describe a

wine. However, when naive wine drinkers first try to

describe wine flavor, they usually find it difficult to

name specific and familiar flavor notes. Standardized

terminology for wine evaluation has been developed

which facilitates development of precise descriptions.

A standardized terminology using analytical terms for

evaluation of table wines is presented in a hierarchical

system in the wine aroma wheel (Figure 1). (A similar

scheme for evaluation of sparkling wine aroma has

also been developed.) The most general terms are

located in the inner tier, with increasingly specific

terms placed in the second and third tiers. In con-

struction of this word list, subjective, hedonic terms,

such as ‘rich,’‘well-rounded,’‘harmonious,’‘ele-

gant,’ and ‘austere,’ which may have meaning to an

individual or group of people but which cannot be

readily defined or standardized, were specifically ex-

cluded. Terms are grouped by similarity of the aromas

where possible. To define the terms, reference stand-

ards can be easily prepared (Table 2).

Descriptive Analysis

0006 In contrast to quality ratings of wine experts, which

provide an overall impression of their preferences but

do not provide description of the flavor or reasons for

the quality assignment, descriptive analysis provides

specific information about the wines, which is figura-

tively a ‘photograph of the flavor.’ Analytical sensory

evaluations, such as descriptive analysis, are con-

ducted under controlled conditions which minimize

bias. For example, to exclude the influence of color,

tests are conducted under red lights or using black

glasses. Tulip-shaped glasses are used for all

evaluations of aroma. The optimum shape for in-

creasing intensity has recently been demonstrated to

be a tall glass with a wide bowl and narrow mouth.

(See Sensory Evaluation.)

0007In descriptive analysis, initially analytical descrip-

tive terms or attributes, such as those in the wine

aroma wheel, are identified which are necessary

to describe and differentiate the wines. For each

attribute, reference standards are provided which

define the specific aroma or taste characteristics and

provide a common point of reference for communi-

cation. Even if descriptive analysis is done informally

by consumers, profiles of wine flavors can be de-

veloped which permit specific comparisons of the dif-

ferences among wines. More formally, data obtained

using trained judges under controlled conditions pro-

vide precise information about wine flavor. Judges are

trained extensively in the use of these terms in discus-

sion sessions and in formal scoring tests, with refer-

ence standards available to define each attribute

clearly. The intensity of each term is then rated in

each of the wines and the data are analyzed statistically

to confirm that the judges are consistent and reprodu-

cible and to determine whether differences among

wines are statistically significant. (See Sensory Evalu-

ation: Sensory Rating and Scoring Methods.)

0008The information provided by this type of analysis

can be illustrated briefly, first, by examination of

results from a descriptive analysis of Napa Valley

Cabernet Sauvignon wines made from vineyards

with different soils. Trained judges rated flavor by

mouth and aroma attributes using the reference

standards described in Table 3. How soil type may

have influenced wine sensory properties is seen in

Figure 2 for two wines which were produced at the

tbl0001 Table 1 Point assignment of the Davis 20-point scorecard

Characteristic Weight

Appearance 2

Color 2

Aroma and bouquet 4

Volatile acidity 2

Total acid 2

Sugar 1

Body 1

Flavor 2

Astringency 2

General quality 2

Explained in detail in Amerine MA and Roessler EB (1983) Wines,Their

Sensory Evaluation. San Francisco: W.H. Freeman.

17–20, superior wines: must have some outstanding characteristic and no

marked defect; 13–16: standard wines with neither an outstanding

character nor defect; 9–12, wines of commercial acceptability but with a

noticeable defect; 5–8, wines of below commercial acceptability; 1–4,

completely spoiled wines.

tbl0002Table 2 Composition of typical aroma reference standards

Term Composition

Berry 1 blackberry, 15 g raspberries, 10 g strawberry

jam, 10 g raspberry jam in 3 ml base wine

Vanilla 0.1 ml vanilla extract in 25 ml base wine

Butterscotch 0.2–0.3 ml butter extract in 25 ml base wine

Vegetative 0.2 ml asparagus brine, 0.4 ml black olive brine,

1.5 ml green-bean brine in 25 ml base wine

Bell pepper 0.1 g fresh bell pepper in 25 ml base wine

Cloves 3 whole cloves in 25 ml base wine

Soy 0.4 ml soya sauce in 2.5 ml base wine

Mint Piece of eucalyptus leaf and 0.05 ml mint

eucalyptus extract in 25 ml base wine

Base wine was a neutral, low-intensity red wine.

Data from Spears TA (1990) Evaluation of the effects of soil and other

geographic parameters on the composition and flavour of Cabernet

Sauvignon wines from the Napa Valley. Unpublished. MSc Thesis,

University of California, Davis.

6218 WINES/Wine Tasting