Innovation and authenticity for winery products

Innovation and

authenticity for winery

products

Introduction

The goal is trying not to decrease the raw material during the processes.

OIV: international organisation of wines.

From 2000 to 2018 the fields use to grape production (vineyard) is decreasing even if the wine production is

increasing. We can see less amount of grapes but more wines; the quality is increasing.

Wine consumption: after the crisis in 2008 the wine consumption has decreased. Now the consumption is

stable.

The world trade is increasing.

Production in Italy

We're producing more wine even if the vineyard extension has decreased.

The 55% of the production of wine is white. We have a lot of wineries and bottlers (people who buy wine to

bottle it).

In Italy today we have more DOC (DPO in English) wines than table wines.

WHO [World health organisation]

They say that the harmful use of alcohol should be reduced and used in moderation, alcohol is toxic for them.

The French paradox was a study by a French

scientist. He put in correlation the fat in animals

(cholesterol) the risk to die for heart disease. Usually,

in countries with a high consumption of fat, the death

rate is higher.

So the study says that if you eat a lot of animal fat you

have a higher risk of die for heart diseases. The study

shows that even if French people eat a lot of cheese

etc. they have a low rate of death for heart disease.

That's because people from other countries don't

drink wines (they contain more antioxidants and other

compounds that protect from bad cholesterol) but

vodka and spirits. It's a met-analysis; he took several

other studies, he collected data from those.

J-curve is a study related to the alcohol

consumption in the daily diet. It shows a

relationship between the daily consumption of

alcohol and the risk of death. If you don't drink any

wine at all you have a higher risk of death than if

you drink with moderation. If you drink a lot, of course, you'll have the highest risk of death.

Chianti is produced with "Governo alla Toscana"; it's a specific protocol to stabilise wines. If you want to

keep it stable you need to remove all the nutrients. Chianti's fermented once than you have some clusters of

grapes from the vineyard and they reach a point in which they're overripe and basically, they become raisins

(they loose humidity, increase the content of sugar). They take this cluster of raisins, they press it and put it in

the young wine that had already been produced. You have a second fermentation that will stabilise the wine.

Definition of wine today

You can find it in the EU regulation 1234/2007, as well as the must and other winery products.

Wine shall be the product obtained exclusively from the total or partial alcoholic fermentation of fresh grapes

whether or not crushed of grape must.

Eu has been divided in several climate areas/zones. In Italy, we need to produce wine with at least 9% VOL

and not more 15%. If the alcoholic strength goes above 15% it has to be called with a different name (liquor

wines, more than 15% and less 22%).

Adding sugar/sucrose is admitted in Northern countries but NOT in Italy because otherwise, they won't be

able to reach 8%.

It's possible to add sugar and neutral alcohol in liquor wines (e.g. Marsala).

In Italy must (also rectified must etc.) might be added to the wine.

Wines should not have less than 3,5 as regards the acidity of the wine (acid tartaric).

Sparkling wines are produced with 2 fermentations or just 1 and they can be obtained from fresh grapes,

wine or must.

Champagne is produced by 2 fermentations: the first alcoholic fermentation to produce ethanol and the

second one to increase the pressure inside the bottle (at least 3 BARS). The alcohol content should be more

than 9%. You can not add CO 2

In natural sparkling wines.

Grape must is the product form fresh grapes (not frozen). If it's a must it can't be fermented. Alcohol not

more than 1%. It is freshly crushed grape juice that contains the skins, seeds, and stems of the fruit.

Rectified grape must: is preserved grape juice that has been rectified, processed to reduce the

concentration of solids other than sugars. It is generally further treated by removing water. It comes from

grape must, after removing all the non-sugary components. It is ideal for the augmentation of the sweetness

of a wine and also for the enrichment of a grape must. It’s syrup basically.

With 61.7% is stable, it inhibit the life of microorganism.

Total alcoholic strength by volume is the content of the actual ethanol inside it + the alcohol that can be

obtained from the sugar in it.

Grape must concentrate is obtained from pressed grapes. Its water content is partially removed by

evaporation. This must is obtained by evaporation to reach a higher content of sugar.

Quality parameters for grape must:

The pH should not be more than 5, it should be acidic;

• The must should be as transparent as possible. 425 nm is for the yellow colour, the browning process

• of any food product. The maximum of absorbance should be 0.1.

This product should not contain sucrose;

• Folin index should be low: that means that the content of interfering contents is low (antioxidants:

• phenols).

Titratable acidity (volatile + non-volatile acidity) is related to sugars content; in concentrate must

• should be low;

Sulphur dioxide might be added (to avoid the browning of wine) but should not more than 25

• milligrams per kg of total sugars;

Total cation content should be low; cations should not be present because only sugar should be

• present (potassium);

HMF is the product of Maillard reaction and if the content of it is high that means the product was

• heated on a direct flame;

Presence of mesoinositol: is a polialcohol and it's a marker of the origin of must. It comes from grapes.

• If it's present it means that only grapes have been used for the must.

Colour intensity of wine ABS 420+520+610 ;

Tonality of wine is related to browning condition of wine (the aging state of wines):

A / A

420 520 .

Wine vinegar is obtained by acetous fermentation of wine and it has a total acidity.

Legge 238/2016 Testo unico del vino: it contains all the EU laws of wine.

New European low no 1234/2007:

DOP (PDO: protected designation of origin).

• IGP (PGI: protected geographical indication). They have a disciplinare di produzione (processing

• rules); the territory is larger than for DOC/DOP.

Varietal wine wine: table wine, no processing rules, no geographical origin.

•

South Tyrol has 7 viticultural areas and 98% of wine produced in Trentino Alto Adige is geographically

protected (60% white wines).

Wine is a biotechnology

Biotechnologies: processes using living organisms (microorganisms, plant or animal cells) or their parts, to

produce goods and services.

Wine is produced from grape must via fermentation.

Parameters influencing winemaking

Raw Materials: Technology:

-

- fermentation conditions, types of yeasts;

grape varieties/blends (uvaggi); -

- type of winemaking process: in bianco or in rosso

pigment profile;

- (with/without maceration), carbonic maceration,

acidity/malic acid concentration;

- others);

grape flavour and aroma. - maturation and storage conditions (maturation

means storage in oak barrels or in stainless steal

tanks);

- stabilisation processes (before bottling we need

to stabilise the wine);

- bottling;

- storage of the marketed product.

Sanitary state of the grapes and maturation are also important parameters.

Composition of grape berry Stems (3%) are not necessary because they're not

•

rich in sugar but in potassium (destabilisation of

wine) and tannins (bitter compounds that we do not

want in wine). They need to be removed because

they can damage the mechanism of some machinery.

If we want to promote the precipitation of

compounds during the first stages of the wine

making process.

Seeds (5%) not to be crushed during the wine

•

making, they contain proteins, lipids and phenolic

compounds with an astringent and bitter taste. Low

content of water.

Skin (20%) contains the pigments, it's important for red wine. At the end of maturation we have the

• formation of volatile compounds (positive odourants) between the pulp and the skin. Sometime we need

them to be realised from the skin to the pulp.

Pulp (75%). The berry is 80% water and the rest is basically sugar. The pulp should be high in sugar and

• low in bitter and astringent compounds.

N compounds are a critical point especially at the beginning of the wine making process. Winemakers

• need to quantified the N in must because the yeast needs the calories from sugar to produce energy but

they need N as well to produce proteins.

Sugars glucose and fructose are fermentable sugars. During the course of fermentation, the yeast converts

• these sugars to alcohol and carbon dioxide. The amount of alcohol produced is related to the amount of

sugar initially present in the juice; thus, by controlling the amount of sugar in the juice, one can control the

amount of alcohol in the resulting wine.

Organic acids are needed in grape pulp to make it more stable (pH low). Three primary acids are found in

• wine grapes: tartaric, malic and citric acids. They’re present as free acids and salts. If there’s a lot of Ca (eg.

when washing the tank with water) we may have precipitation of tartaric acid.

Others

• - Lecithin.

- Phytin attracts iron.

- Calcium oxalate will form salts which will precipitate in the wine so it’s not really appreciate in

winemaking.

- Pruin is a layer of thick wax on the outside of the berry produced by the fruit to reduce de dehydration

during the maturation. Yeasts are outside, when we crush the berry this action will promote the

spontaneous alcoholic fermentation.

Tannins are pigments of red wines. The only difference between the white and red skins is the presence of

• anthocyans in the red berry.

The number of the of seeds (up to 4 in one berry usually) is related to the final quality of wine: lower sugar and

higher acidity. They can release the astringency into the wine.

Layers of the ripe grape pulp

The berries are formed by multiple layers that divide the different part of the berry:

- inner layer

the is in contact with the grape seeds which absorb sugar because they’re used as a storage

for nutrients; the bitter compounds are released in the internal layer from

the seeds. This layer is low in sugar and rich of organic acids;

- intermediate layer

the has a high content of sugar and a low content of

phenolic compounds (absence of astringency and bitterness);

- outer layer

the is in contact with the skin so it is rich of phenolic

compounds (released by the skins, they are anthocyans in the case of red

wines), poor of acids and sugars.

When the grape berries are crushed what everyone

wants to obtain are the outer and intermediate layer

and it would be better to exclude the internal one.

Soft pressing (horizontal) means that the wine will be obtained from the outer and

intermediate layer. The pressure applied is 0.5-0.8 Bar. There’s a bag inflated with air

and the grape berries will be pressed against the wall with the same homogeneous

pressure. In this way the juice is richer of sugars and poor of acids. The juice is

extracted from the intermediate layers of the berry. The aroma and phenolic

compounds are preserved from oxidation. Less acidic wines are obtained through this

technique.

Strong pressing means increasing the pressure to obtain more wine but it’s called strong press (vertical

press) and the quality is lower. High pressure up to 4 Bar.

It’s not possible to apply a homogeneous pressure. So the juice is extracted from the internal layers of the

berry. The juice is more acidic and less sweet.

More acidic wines are obtained with this technique.

Anthocyans

Anthocyans are the main pigments present in red wines.

They are glucosides: upon acidic hydrolysis, anthocyanins release the anthocyanidin and the sugar (usually

glucose).

Anthocyans take their names from flowers\plants.

Most frequently occurring in nature are: malvidin, cianidin, peonidin, delphinidin, petunidin, pelargonidin.

They’re basically phenols connected to glucose. In acidic condition, anthocyanin appears as red pigment.

The compound is red because the electrons go through the central ring and there's

a resonance that produce the colour.

Malvidin-3-G is formed by two phenols, one of them is bound to a molecule of

glucose and one ring with two methoxy group and one hydroxyl.

Anthocyans can be found as esters (acylated anthocyans), especially in young red

wines, in which the hydrolysis is not yet complete. So we may have two different

types of anthocyans:

Acylated anthocyans and

• Non-acylated anthocyans.

•

The case of Brunello di Montalcino DOCG

Sangiovese grapes (and thus wine) do not contain acylated anthocyans: this is very important for authenticity.

This means that if a wine is produced with Sangiovese grapes it does not contains acylated anthocyans (if

you find them inside it is a fraud).

We can get the pigments profile of a wine thanks to the chromatography.

[Brunello and Chianti are the main wines produced by Sangiovese]

Brunello is a wine produced in a small of area of village of Montalcino, only Sangiovese collected from this

small area in Tuscany. It’s dry: a dry wine is a wine that has no residual sugar, meaning it isn't sweet.

The method of OIV describes a method of HPLC that can be used to identify the profile of anthocyans. They

use standards compounds: pigments that are not acylated are eluted before, meanwhile the acylated ones

are eluted after.

Quantitative analysis with a calibration curve: the signal of standards compounds should be

proportional.There are some papers in literature that show us that Sangiovese grapes have not acetate, very

low coumarylated anthocyans, no malvidin-caffeato whereas other grape variety have a lot of these

compounds.

We're looking for new markers to avoid more frauds.

Use of the anthocyans for the authentication for wine. They’re crucial for the quality and quality assessment.

Other phenols that binds to anthocyans to form more stable pigments, the colour for he wine become more

stable.

In the case of Brunello di Montalcino anthocyans, after few years, will decade so we are going to have a very

small fraction of the original anthocyans that were present into the grapes skin. However the colour of the

wine is till deep red even if the anthocyans are lower in concentration. It means that there’re some other

compounds which are important to determine the final colour of the wine.

Importance of the anthocyans because their profiles are used to authenticity purposes as well.

The colour of wine can change according to the pH. This happens because the free form of anthocyans

has a different conformation according to the pH.

The colour of wine turns into intense red cherry if you put some lemon drops whereas if you put some solid

soap that is alkaline the colour turns into grey\green\blue.

- At pH 3 we have a red form because the electrons play a resonance all around the structure of the

molecule, this lead to a deep intense red colour of this pigment.

- At pH 7 or higher the resonance changes and there’s the

formation of the para-quinoid form and we have an

anthocyans that has lost the red colour.

By changing the pH we could go back to the red colour.

This means that in winemaking process, every process which

leads to an increase of pH, will change the final colour of the

wine pH is 2.8-3.8.

wine. The At

this pH just 50% of anthocyans

are coloured, half is colourless.

By increasing the pH, as well as

the colour changing, there is the

possibility to go towards a

microbial spoilage and an oxidation process of wine. This is the reason why the

pH should always be monitored.

When the pH increase, and the pH is higher than 4 there are some colourless forms of anthocyans so the red

wine hue will decrease.

Even if we have colourless forms, wine is still red because these are not the only molecules responsible for

the colour of wine.

There are some other molecules which contribute to the colour of wine.

The colour is given by a reaction that occurs during winemaking and storage of wine. It’s a condensation

between free anthocyans which are coloured (malvidin-3-G) and procyanidins (only 2 -OH, otherwise we have

proanthocyanidins which is the general name of all the polymers containing catechins that are also called

condensed tannins: formed by several units of catechins or gallocatechins). Malvidin-3-G polymerises with a

procyanidin forming a polymeric pigment. This is a reaction that takes place in red wines especially during the

storage when it stays in the barrels or tanks and it needs a small amount of oxygen.

From where do we take the oxygen? Not from the sealed stainless steel tanks (we fill them completely with

wine so there’s no oxygen inside), but me might have residual oxygen in oak barrels. Indeed they might have

an internal surface with oxygens bubbles released from wood. This reaction does not occur if we put the wine

in steel tanks, so the colour of wine won’t be stable because the colour is given just by the free anthocyans.

If a winery uses stainless steel tanks, oxygen can be provided through very low flow of air into the bottom of

the tanks by using compressed air (tank connected to a manometer, air pass through a filter candle). This

process is called micro-oxygenation. That promotes a very slow oxidation of proanthocyanidins with the

formation of the polymeric pigment. This polymeric pigment is the main responsible for the final product

colour.

This process is called phenolic coupling polymerisation. The polymeric pigment is formed by several units of

catechins. It’s a huge molecule and it can be formed by malvidin + 6/8 units of flavonoids (catechins).

These pigments can’t be bleached by SO (antioxidant and antimicrobial). The bleaching process is not

2

possible when these pigments are present in wine because the SO2 can’t attack this kind of molecul