School for Viticulture and Enology

Modern Trends in Winemaking

This course is part of the programme:
Bachelor's programme in Viticulture and Enology (1st level)

Objectives and competences

Student gets knowledge about new techniques, already used in the wine making

technology, the suitability of their use regarding the wine quality and their influence on

the wine character.

Prerequisites

For understanding of new technologies students has to be familiar with chemistry, physics and basic enology and viticulture.

Content (Syllabus outline)

Lectures

White wine

The white wine technology is now going in to two different directions:

  1. The increase of sort character – especially of the grape sort aroma,
  2. The increase of extractability and stability of white wines (the maturing of wine on

    the lees or addition of the died yeast cells during the wine maturation).

The increase of white wine sort character

Monoterpens (sort aroma carriers) are found in the grape berry skin and in the grape

mould. They are synthetisised only 7-10 days before the full grape ripeness. The

mission of the technology is to preserve or increase the extraction of these compounds

from the berry skin as much as possible. This can be reached with:

  • Short term cold maceration of de-stemmed white grapes mesh (under 10°C, 6-12

    hours). Terpens are bonded to the pectin and sugars with ester bonds. The

    addition of the pectolitic enzymes with ß-glucosidasic activity is possible to

    release the bonded pectin or the use of specially selected yeasts (the yeasts

    aroma) which contain this enzyme. This is how the aroma carriers are released

    during the alcoholic fermentation.

  • Longer contact between the berry skin and must can be achieved in the process,

    where 2-3 % of mature berries are added during the fermentation and than

    removed with the first racking of the wine. Wines, produced by the technology,

    described previously have extremely expressed sort bouquet, but because of

    lower fermentation temperatures (below 15 °C) posses less extract. The use of

    enzymes is recommends for the wines that are consumed in one to two years

    from the production, especially for the aromatic wines (sauvignon, muškat).

The increase of white wines’ extractability

Extractability can be increased by alcoholic fermentation under higher temperatures

(above 20°C), where more glycerol is produced, as well as higher amounts of higher

alcohols (heavy flavor). Because of much intense fermentation and CO2 formation soft

bouquet can be lost and higher alcohols formed during the fermentation can cover the

sort character. Some people in wine trade business say that hiperoxidation of the white

must is the best solution, where already pressed must is oxygen aerated. Added oxygen

enhances the bonding of polyphenols with the proteins. The clarification of the musts is

quicker, higher aeration enables faster multiplication of the yeasts and consequently

larger amounts of glycerol is produced. Addition supply of the oxygen can cause the

monoterpenes’ oxidation-which are known as sort aroma carriers. This procedure makes

such wines richer in taste (good maturation) with less expressed sort bouquet. More

recently, especially in the southern Slovenia wine growing parts (in Brda and Koper

region) is for wines, rich in alcohol (above 13 % v/v alcohol), recommended wine

maturation in wooden barrels on the lees (or in stainless steel tanks with periodical

ventilation with oxygen) and stirring the lees. Addition of already dead yeast cells is

possible. Such maturation is going on for 6 ore more months, by stirring the lees 2-3

times per week. Malolactic fermentation happens at this kind of wine maturation (the

transformation of malic acid to lactic acid), from the dead yeast cells (added or in the

lees) yeast proteins are extracted – manoproteins. They are composed from the amino

acids and sugar part-glucose and mannose. The main role of manoproteins is:

  • Wine aroma bonding – preserving for longer period,
  • Stabilization of the tartrates crystallization (a substitute for the metatartaric acid)
  • They prevent the protein haze – by bonding the termo-labile proteins (lesser needs for the bentonite).

Such wines are chemically more stabile, rich on extract, and due to formed lactic acid

softer, fully tasted and well balanced.

Red wines

Carbon maceration:

  • Short-term maceration for young wines such as Beaujolais type,
  • Long term maceration for red wine aging,
  • Prolonged classic maceration.

Short term carbon maceration of the whole clusters, or only

partly stemmed grapes (1/3) is performed in closed

high-pressure tanks with 1-1,5 bar of up-pressure. Released

CO2 during the alcohol fermentation is regulated with the

pressure reducing valve. Alcoholic fermentation is performed

in the berries. Due to hard living conditions, the yeasts are

now forming more fruity higher alcohols, fatty acids and their

esters. Short-term maceration lasts for 2-3 days. The color

compounds are extracted in those period-only anthocyanins but

not other phenols. Such young wines have intense ruby color

tens, fruity bouquets, velvety, a bit tannin and due to CO2,

fresh.

Long-term carbon maceration can last even for 14 days or

more. After 4-5 days, are also tannins (beside anthocyanins)

extracted from skins and seeds. Such wines are rich in

fermentation aroma (heavy aromas from higher alcohols), chewy

and prepared for at least 2-3 years aging. In that period, the

tannins are than condensated, become insoluble, therefore less

tasted and softer.

Prolonged classical maceration, even to one month is performed

at 25-30°C, with “punching down the cap”. After the alcoholic

fermentation, when the “cap” of skins is resuspended, the post

maceration is going on, a week or 2, just to finish malolactic

fermentation. These wines preserve more sort character, are

rich in extract and very good for further maturation and

aging.

Integrated wine making

Like in grape growing, there are some limitations also in the

integrated wine making processes, which lower the use of

means, which are bad for human health and also environment and

also lower the environment pollution and

exploitation. Alternative technologies will be presented,

regulations, book keeping of the tracebility, labeling and

marketing of integrate made wine.

Field observations

The visit of highly sophisticated and modern wine cellar is

planned and see practical performance of some new

technological procedures. One world known wine exhibition will

be visited, where some new things, which are implemented in

the wine technology will be presented. (ENOVITIS).

Readings

Pascal Ribereau-Gayon. 2006. Handbook of Enology (Hardback), Volume 1 in Volume 2. John Wiley & Sons Ltd

Professional and scientific papers

Lecture notes

Assessment

Written and oral assignments.

Lecturer's references

Assistant professor for the field of Enology, employed at Agricultural Institut of Slovenia, external coworker at School for viticulture and enology.

1. ŠUKLJE, Katja, ANTALICK, Guillaume, COETZEE, Zelmari, SCHMIDTKE, Leigh, BAŠA ČESNIK, Helena, BRANDT, Jeane, DU TOIT, Wessel Johannes, LISJAK, Klemen, DELOIRE, Alain. Effect of leaf removal and ultraviolet radiation on the composition and sensory perception of Vitis vinifera L. cv. Sauvignon Blanc wine. Australian journal of grape and wine research, ISSN 1322-7130, 2014, vol. 20, iss. , str. 223-233, doi: 10.1111/ajgw.12083. [COBISS.SI-ID 4475240]

2. PAJOVIĆ, Radmila, RAIČEVIĆ, Danijela, POPOVIĆ, Tatjana, SIVILOTTI, Paolo, LISJAK, Klemen, VANZO, Andreja. Polyphenolic characterisation of Vranac, Kratosija and Cabernet Sauvignon (Vitis vinifera L. cv.) grapes and wines from different vineyard locations in Montenegro. South African Journal for Enology and Viticulture, ISSN 0253-939X, 2014, vol. 35, no. 1, str. 139-148. [COBISS.SI-ID 4465768]

3. COETZEE, Carien, LISJAK, Klemen, NICOLAU, Laura, KILMARTIN, Paul, DU TOIT, Wessel Johannes. Oxygen and sulfur dioxide additions to Sauvignon blanc must : effect on must and wine compostition. Flavour and fragrance journal, ISSN 0882-5734. [Print ed.], May 2013, vol. 28, iss. 3, str. 155-167, ilustr., doi: 10.1002/ffj.3147. [COBISS.SI-ID 4000872]

4. JENKO, Mojca, LISJAK, Klemen, KOŠMERL, Tatjana, ČUŠ, Franc. The influence of yeast strain combinations on the quality of sauvignon blanc wine. Food science and technology research, ISSN 1344-6606, 2013, vol. 19, no. 1, str. 7-15. [COBISS.SI-ID 4143464]

5. ŠUKLJE, Katja, BAŠA ČESNIK, Helena, JANEŠ, Lucija, KMECL, Veronika, VANZO, Andreja, DELOIRE, Alain, SIVILOTTI, Paolo, LISJAK, Klemen. The effect of leaf area to yield ratio on secondary metabolites in grapes and wines of Vitis vinifera L. cv. Sauvignon blanc. Journal international des sciences de la vigne et du vin, ISSN 1151-0285, 2013, vol. 47, no. 2, str. 83-97. [COBISS.SI-ID 4234600]

6. ŠUKLJE, Katja, GOBLER, Nico, COETZEE, Zelmari, LISJAK, Klemen, DELOIRE, Alain. Methoxypyrazines and greenness in wines: myth or reality? : a few perspectives. Wineland, ISSN 1562-7012, May 2013, [6 str.], ilustr. [COBISS.SI-ID 4246376]

7. ŠUKLJE, Katja, LISJAK, Klemen, BAŠA ČESNIK, Helena, JANEŠ, Lucija, DU TOIT, Wessel Johannes, COETZEE, Zelmari, VANZO, Andreja, DELOIRE, Alain. Classification of grape berries according to diameter and total soluble solids to study the effect of light and temperature on methoxypyrazine, Glutathione, and hydroxycinnamate evolution during ripening of Sauvignon blanc (Vitis vinifera L.). Journal of agricultural and food chemistry, ISSN 0021-8561, 2012, vol. 60, iss. 37, str. 9434-9461. http://dx.doi.org/10.1021/jf3020766, doi: 10.1021/jf3020655. [COBISS.SI-ID 3918184]

8. JANEŠ, Lucija, LISJAK, Klemen, VANZO, Andreja. Determination of glutathione content in grape juice and wine by high performance liquid chromatography with fluorescence detection. Analytica chimica acta, ISSN 0003-2670. [Print ed.], 2010, vol. 674, iss. 2, str. 239-242, doi: 10.1016/j.aca.2010.06.040. [COBISS.SI-ID 3347048]

Nagrada: Nagrada za prispevek k trajnostnemu razvoju družbe za leto 2010, Javni sklad RS za razvoj kadrov in štipendije

9. ŠUKLJE, Katja, GOBLER, Nico, COETZEE, Zelmari, LISJAK, Klemen, DELOIRE, Alain. Manipulating light in fruit zone improves wine quality : winegrowing. Practical winery/vineyard, ISSN 1057-2694, Jan. 2014, str. 27-34. [COBISS.SI-ID 4158056]

University course code: 1VV310

Year of study: 3

Semester: 1

Course principal:

Lecturer:

Assistant:

ECTS: 6

Workload:

  • Lectures: 45 hours
  • Field exercises: 10 hours
  • Individual work: 125 hours

Course type: lectures, field practice

Languages: slovene and english

Learning and teaching methods:
lectures, field observation, students' independent work