From the vineyard, but not from the grape: launch of "SusBev" project in Germany

At the beginning of the year, a multidisciplinary German consortium of biotechnologists, oenologists, winemakers and sustainability experts started work on a state funded innovation project: the "Sustainable Beverages" project, or "SusBev" for short, is part of an overarching research project on Bioeconomy.


The aim of the project is to use agricultural residues and side streams from viticulture and other regional agricultural processes to produce healthy and tasty beverages and food.


In their first task, the researchers are working on using the leaves of new grape varieties adapted to climate change to make wine-like drinks. The vine leaves and shoots of these varieties, which have not yet been used as a raw material, are suitable because they have an attractive, varietal flavor (like the berries from which wine is made). In addition, their resistance to fungal attack means that the plants require less pesticide treatment, which is beneficial for the environment as well as for consumers.


BRAIN Biotech AG, Tropical Viticulture Consultants (TVC), Zukunftsweine GmbH (ZW) and Provadis Hochschule are participating in the SusBev project. In particular, TVC provides expertise in the selection, harvesting and processing of suitable side streams. Find out more about the project here and stay tuned for exciting novel grape-based beverages.                         


(Source: BRAIN Biotech, Press Release 14 March 2024)



May is the month of sprouting trees..and vines..and ideas!

TVC founder Wolfgang Schaefer and Pit Hoehnen are tired but happy after a long day of picking and processing fresh PIWI grape shoots and leafs.


For this product trial, TVC is teaming up with cooperating wine-growing estates from the grape growing region Rheinhessen that are interested in broadening their non-alcoholic product range.


One such trial product relies on the collection of young, untreated grape leafs and shoots. These are shredded and then soaked with demineralized water for several hours, upon which they are pressed and then pasteurized, before being stored in 50l stainless stell KEGs. The thus obtained grape leaf infusion can be stored at around 6°C for a prolonged period. The infusion can be used to improve classic dealcoholized wine products, but its unique aroma and acidity also make it a promising basis for stand-alone innovative drinks with zero alcohol.


The idea was initially fostered by TVC in tropical grape growing regions, and it first seemed hard to apply it in temperate climate because it is quite impossible to find untreated vines that are geared for grape production. With the new generation of PIWI-growing estates, however, a special winter pruning technique was developed that allows for both the collection of up to 50% of untreated leafs in May AND a regular grape harvest in September. If that isn't the prime example of a win-win situation, what is? We are very excited for the upcoming developments and will keep you posted for sure!





Grapevine (Vitis Vinifera) is chosen as medicinal plant of the year 2023

In order to promote the knowledge of medicinal plant properties, the German Natural Healing Association Theophrastus (NHV Theophrastus) annually appoints a respective plant as 'plant of the year'. Replacing 2022s nettle, the year 2023 is dedicated to the grapevine.


The family of Vitis Vinifera composes almost 10,000 varieties worldwide. The plant has been cultivated for millenia, and the healing properties are well known since ancient times. Apart from being rich in fibre and vitamins, grapevines produce high levels of anthocyanins and polyphenols, which are known for their antioxidant properties and related health benefits in regard to heart and vascular diseases, diabetes, and certain cancers. These properties can be found both in the leafs and the grapes, and are more pronounced in some varities than others (e.g. deep red leafed or certain PIWI varieties).


Further processing, such as producing vinegar, adds more health benefits in the form of becoming an disinfectant, fever reducing, and digestive agent. And, if drunk in moderation, wine of course is a very tasty processed form of grapes. Cheers then to you, Vitis Vinifera!


You can read the whole article in German here.


(Source: NHV Theophrasuts, November 2023,



Join the Online PIWI Summit on May 30, 18:00 - 20:00h (CET)

PIWI International is inviting you to their second online summit this May. Join for free and hear about the newest developments in the field of PIWI worldwide.


TVC founder and CEO Wolfgang Schaefer will be among the speakers and present an insight into "Brave New Wines - The potential of fungus tolerant cultivars in the tropics". See you on tuesday, May 30, then!



TVC is hiring - active partner & shareholder wanted


TVC is a long-standing small consultancy based close to Frankfurt/Main, Germany. Our specialization in the field of tropical viticulture and oenology engages us with a wide range of clients from all around the globe, covering everything from short term assessments to multi-decade complex projects. Present assignments include Bhutan, Ethiopia, Ghana, Nepal and Thailand.


We are currently looking for a committed and experienced oenologist / winemaker / beverage technology engineer (ideally all at the same time) with good command of both written and spoken English. International travel of 1-6 weeks plus videocall settings and online consultation services should not pose a problem.


We are offering the unique opportunity to join our company (GmbH) as an active partner and shareholder. A comprehensive onboarding and practical induction training by the two current associates is provided. If you would like to know more, get in touch via


And please feel free to spread the word. Thank you!




Friendship forged at Nepals Pataleban Vineyards

Sometimes its just a matter of chance to make good things happen:

Following a TVC posting at Geisenheim, recent graduate Sebastian Erbeldinger applied for a volunteer engagement at Pataleban Vineyards in Nepal. The growing estate and winery was looking for technical support during the upcoming harvesting season.


24-year old Erbeldinger from the family run winery Bastianshauser Hof in Rheinhessen was awarded a DLG Award for 'Young Winemaker of the Year' in 2019, and has working experience in New Zealand and South Africa. The idea of spending six weeks at Pataleban winery in Nepal was enticing, and, as it turned out, a perfect fit!


On site he was welcomed by Sataya Bohora, Patalebans winemaker and heart&soul of the winery for many years. A successful grape harvest and installation of new machinery later, we are happy that the viticultural ties between Nepal and Germany are deepening.





Nepalese winemaker Siddartha Karki during viticultural training at the Mosel river

The first winery in Nepal is getting ready for future challenges. Kumar Karki, who founded the countrys pioneer estate, is supporting his son Kumar Karki in receiving a classical oenological training at the Mosel river in Germany. The region is known for some of the most renowned wineries in Germany, and with its steep slopes resembles at least some of the qualitites of Nepalese viticulture. Siddharta Karki is also closely mentored by Tropical Viticulture Consultants (TVC).  In a short interview with Wolfgang Schäfer, Siddharta talks about his impressions and plans.

DAS DEUTSCHE WEINMAGAZIN Ausgabe 16/17 vom 21.8.2021 ab Seite 52.


Find the full article in German version on our Media page.



TVC Article about Nepalese Viticulture in "Das Deutsche Weinmagazin"

When thinking about Nepal and the breathtaking snow-covered mountain range of the Himalaya, one does not usually bear lush grapes and sweeping vista of vineyard terraces in mind. However, this is exactly what you’ll find when visiting the "Pataleban Vineyard Winery" about 1.5h west of Katmandu!

Learn more about the particularities of viticulture under these extreme circumstances in this brief article by long-standing international grape growing consultant Wolfgang Schaefer from TVC and Dr. Dietrich Marbé-Sans, DLR RNH Oppenheim.

DAS DEUTSCHE WEINMAGAZIN Ausgabe 16/17 vom 21.8.2021 ab Seite 52.



Find the full article in German and English version on our Media page.




News Article "Adapting to climate change: How Thailand’s tropical wines are teaching the old world new tricks"

Climate change is affecting viticultural production around the globe.

How winemakers in Thailand deal with the resulting challenges, and how expertise gained in the tropics can be relevant for future European viticulture is laid out in this Channel NewsAsia article by Jack Board. 


The article features interviews with Nikki Lohitnavy, winemaker and oenologist from GranMonte wine estate, and with Hans-Peter Hoehnen, TVC founding member and long-standing viticultural consultant for GranMonte and Siam Winery. Well written and poignant, it gives a great overview and makes for an informative read.

Niki Lohitnavy, GranMonte Estate

(Source: CNA, 2021 / Image:



There is always a first time..TVC Geisenheim spring lecture online only

The lectures on tropical viticulture at Geisenheim University are always special events, often including tastings of wines from unusual places and cultivars. But due to Covid-19 restrictions, this years spring course could only take place digitally. After a quick trip to the electronics shop, and with support from the Geisenheim IT department, Wolfgang Schaefer was set up for the first online lecture ever. It went surprisingly smoothly and students were curious as always!





Pataleban Vineyards from Nepal join International PIWI Assocation

The International PIWI Assocation is a research network aiming at the further dissemination of fungus resistant grape varieties (PIWI = Pilz widerstandsfähig = German for 'fungus resistant'). The association encompasses over 350 members worldwide from now 19 countries in Europa, Asia and North America.


Pataleban Vineyards is a client of TVC and located close to Kathmandu in Nepal. The vineyard and resort was established in 2006 by Kumar Karki, an innovative entrepreneur who aims at developing eco-tourism, horticulture and organic farming on their estate. The terrain in the area is truly mesmerizing: with an altitude difference of 640m from the lowest to the highest vineyard terraces -within the same valley!-, Pataleban boasts one of the steepest vineyards in the world. Water supply, pest control, and short cultivation periods are other challenges. Fungus tolerant grape varieties offer great potential for viticulture under such less-than-ordinary circumstances, and first field trials with PIWI cultivars are under way in Nepal. Furthermore, Mr. Karki's son Siddharta Karki will complete an internship in a German winery in fall 2019, and plans to enroll for a degree in "International Wine Business" at Hochschule Geisenheim University in the following year.


Welcome then to the newest member, Pataleban Vineyards, and to a succesful cooperation!


Juror at the International PIWI Wine Award 2019

Wolfang Schaefer from TVC recently had the honor of tasting and assessing some of the latest 471 PIWI-wines from 14 countries submitted to the jury at the 9th International PIWI Wine Award.


Nearly all producers had to cope with the effects of last years extremely hot summer, resulting in low acidity and reduced extract density. Climate change has thus already become a tangible factor for wine making. It is expected that the increased irregularity of temperature and rainfall will influence ripening time, yield, and fungal infestation rates.  PIWI or fungus resistant grape varieties (PIWI = Pilz widerstandsfähig = German for 'fungus resistant') require significantly reduced fungicide applications. The reduced input of heavy machinery in the vineyards also leads to a lowering of CO2 production per hectar, and more resilient soils.


Martin Darting, developer of the applied world-renowned PAR® tasting method: "Hence my appeal to wine lovers: be open to the new grape varieties and support PIWI. Demands of the market increasingly force wine-growers to plant resistant grapes. Year after year, the International PIWI Wine Award illustrates that these varities also deliver high-quality and appealing wines."


A press release can found here, and the complete ranking including PAR assessment sheets here.


(Source: TVC, November 2019 & PIWI International / Image:



A Grape is Born - Successful Breeding of First Georgian PIWI Cultivar

Mr. Erekle Martiashvili (left) planting seeds of the new Rkatsiteli  X PIWI cultivars at Saguramo, Georgia.


For the first time since the country's independence, new fungus tolerant grape cultivars have been bred and are now successfully growing at the PIWI grape breeding center founded in Georgia last year. The germination and growth rates of a dozen of crossbreeds between indigenous Georgian grape varieties and established PiWi cultivars are very promising. The Georgian manager of the program, Mr. Martiashvili, continues to work closely with renown grape geneticist Valentin Blattner from the Institute of Ecology and Grape Breeding in Switzerland. We are all very excited to see how the young plants will continue to fare and how they will like their new "home" outside at the Saguramo trial fields. (Source: TVC, Tbilisi, May 2018)



Premium Quality "Saperico" Grape Juice and Tea in Georgia

After two years of consultancy and the establishment of cooperations with local farmers and entrepeneurs, TVC is proud to welcome the new "Saperico" brand now on the market in Georgia.


"Saperico" stands for high quality grape products made from the unique Georgian grape cultivar Saperavi. "Saperico" grape juice is a single-origin, deeply coloured juice made from freshly pressed grapes, and only gently pasteurized to maintain the richness of taste and exceptional levels of healthy anthocyanins and polyphenols.


Even more unique is the second of "Saperico" products: or have you ever tasted grape skin tea?

After pressing the grapes, a large amount of crushed grape berry mush remains. As the berries contain the highest amount of antioxidants and sweetness, it is only natural to also use these excellent fruits! The mush is dried and then ground to a fine powder, which is then filled into tea filter pads to provide you with a wonderfully lilac coloured, refreshing and nutty tea with great health benefits.


(Source: TVC, Tbilisi, January 2018 / Image:



Novation in Grape Vine Breeding in Georgia

Valentin Blattner (left) supervising field trainings at Saguramo (middle) to boost Rkatsiteli variety (right).


The country of Georgia is one of the cradles of wine production and home to around 500 indigenous grape varieties. With the end of the Soviet Union, however, fewer investments have been made and breeding programs were phased out. The last decade has now seen a revival of Georgian viticulture with new agencies and training programs, and an already impressive increase in wine production.

To ensure future quality winemaking, Georgian grape varities need to be adapted to the now omnipresent Oidium and Peronospera diseases. One way of adding resilience is a breeding program which incorporates the latest generation PiWi (fungus tolerant) grape varities.


For that purpose, TVC has invited and hosted reknown grape geneticist Valentin Blattner from the Institute of Ecology and Grape Breeding in Switzerland to share his know-how with Georgian counterparts like Prof. Dr. Ujmajuridze from the Scientific Research Center for Agriculture in Saguramo, and Prof. Dr. Chichua from the Agricultural University in Tbilisi. Mr. Blattner and his colleague Doris Gralimund spent several days in Georgia to set up a breeding program, demonstrate new breeding techniques, and train selected young viticulturists. We are very excited to see how the new crossbreeds will turn out and hope to see Mr. Blattner in Georgia again soon. A big thank you to all involved!                                            (Source: TVC, June 2017 / Rkatsiteli image =



Proudly Presented by TVC: The World's First Grape Leaf Soda KISUU!

Everybody knows wine, secco, or grapejuice..but have you ever considered a drink made from grapeleafs? KISUU is the world's first Grape Leaf Soda and was very well received at this year's PROWEIN fair in Düsseldorf.
Grape leafs contain very high levels of minerals, tartaric acid, and antioxidants. Many cultures cherish the young leaves as a healthy vegetable and ingredient of tea. The wine experts from TVC and Chaivallier took this idea a step further and created KISUU, a softdrink for connoisseurs. Tartly, refreshing, unique.

The name KISUU  is derived from East Africa and means “good spirit”. Good spirit – no spirits is our slogan and means that you can enjoy the best of the vine without a drop of alcohol. The lightly sparkling KISUU only contains cold-brewed grape leaf extract, spring water, and a tad of grape juice.


We are still in negotiations with producers and distributors for our market launch in Germany.


TVC Contributes to 2017 ASIAN WINE REVIEW

From countries with millenia of wine making experience to such with no previous traditions, Asia is hugely diverse and up to now relatively uncharted terrain for wine lovers. Over the past decades, however, a rapidly growing modern wine industry has evolved. While a series of trophy winning wineries are gaining international attention, avid local wine professionals such as the Hong Kong based "The Flying Winemaker" lead a "vino revolution" aimed at changing the way wine is perceived and enjoyed in Asia.


One of the most important venues of these exciting developments is the Asian Wine Review (AWR), which is published once a year and provides information on cultivars, wineries, the Asian wine business in general, and an evaluation of select Asian wines by tasting notes and scores. The review is an excellent way to familiarize oneself with the vibrant Asian wine scene and discover some truly unexptected wine gems. With more than 30 years of viticultural experience in Asian countries, TVC is proud to contribute to this years edition. Enjoy our editorial "A short history of tropical viticulture".

(Source: &, November 2016)




Now Available in Tbilisi: Saperavi Grape Juice by TVC

When visiting Georgia, one will inevitably encounter the famous "Saperavi" cultivar and the full bodied, aromatic wines tradtionally made from it. As a teinturien cultivar, both the grape flesh and skin are of a deep red colour. Research from the past two years has shown that this vine produces grapes with exceptional levels of anthocyanins and polyphenols, which are known for their antioxidant properties and related health benefits.


While "Saperavi" wine is delicious, there are of course numerous situations when a non-alcoholic beverage might be a better choice. In cooperation with the Agricultural University of Georgia and selected grape growers from Georgia, TVC has therefore developed and produced a single-origin "Saperavi Grape Juice". The high quality juice is produced with care, contains no additives or preservatives, and remains unfiltered to boost antioxidant capacities. Health-conscious consumers can now enjoy a refreshing non-alcoholic drink with the same benefits of a mouthwatering "Saperavi" but without alcohol!


Trial production has started in October 2016, and the distinctive 0.33l bottles with the black "Saperavi Grape Juice" label will soon be available in selected winery restaurants, vino-therapy outlets, and health food stores in Georgia.

If all goes well, commercial production will ensue in October 2017.  (Source: TVC, Tbilisi, October 2016)



Powerful PIWIs - Impressive Results of Tropical Test Trials And Spreading Commercial Cultivation

PIWI Grape Variety "Rubin Golodrigi"
PIWI Grape Variety "Rubin Golodrigi"

PIWIs, or fungus resistant grape varieties, have been grown by TVC on test trial sites in Asia since 1993. The experience of these last decades has TVC fully convinced: PIWIs are one of the most promising innovations in tropical viticulture!


The results from trial sites as diverse as Curacao, Indonesia, Myanmar, the Phillipines, and Thailand are remarkable. With an increasing range of high-quality PIWI table and grape vine varieties, local conditions can be well catered for, and the resulting grapes are of high quality. In addition, the effect of reduced agrochemical treatments is even greater than expected: in Thailand, applications in PIWI sites could be cut by 50%, and even higher reductions are possible in regions with less pronounced monsoonal climate. This means a considerable economization of expenditures, but also significantly reduced environmental pollution and more carbon-footprint friendly vine production.


While continuing field trials, TVC is therefore now starting to provide support for the first commercial PIWI cultivation in the tropics and subtropics. If you are interested in learning more about this great innovation, please contact us! For more information on PIWIs, please feel welcome to visit PIWI International.

(Source: TVC, September 2015 / Image: 


New Cooperation On Red Grape Leaf Production with ELKANA in Georgia

Red grape leaves are in ever-growing demand for the production of vein medication. The number of suitable cultivars are, however limited, and leaves have to be grown completely organically to minimize residues. It is therefore with great pleasure that we announce the newly sealed cooperation with the organic agriculture consultancy "ELKANA" from Tbilisi. Georgia, the cradle of over 300 autochthone grape cultivars, happens to be the home of some of the best of teinturien (=red leafed and fleshed) cultivars in the world. The "Saperavi", for example, is the only teinturien cultivar which is used for single-origin wine production and that with astonishing results! It also is a fungus tolerant cultivar, which is why coincidentally Valentin Blattner has been already propagating "Saperavi" and will surely introduce new dimensions for its cultivation. ELKANA are accomplished promoters of organic agriculture, including viticulture, and will support the new red grape leaf project with their valuable local expertise. First field visits in Georgia have been very promising, and we are very much looking forward to the BIOtiful cooperation with ELKANA!

(Source: TVC, Tbilisi, December 2014 / Image:



Launching of Asian Wine Producers Association

With the launch of the Asian Wine Producers Association, a pan-Asian network of wine producers join forces in their strive to shape and represent the new Asian wines from vine to wine. Created in Hong Kong during the 2013 Hong Kong International Wine & Spirits Fair, the association picked up its activities in 2014 and reunites some of Asia’s top wineries, two of which are also clients of TVC. Congratulations to all!

(Source:, December 2014)


Fruitful meetings at the 4th International Symposium on Tropical Wines in Brisbane

The 4th International Symposium on 'Tropical wines & Grape and wine production in diverse regions' was held from August 17-22 in Brisbane, Australia this year as part of the International Horticultural Congress (IHC2014). The symposium offered a two day programme with varied presentations and our session, too, went smoothly thanks to the great organization and the attentive audience. It was a great to catch up with colleagues, compare notes, and make new friends in the pleasant setting of Brisbane. We are already looking forward to the next symposium in 2018 - see you in Istanbul, Turkey! 

(Source: TVC, December 2014 / Image:




New Cooperation with Renown Grape Variety Grower Valentin Blattner

After several meetings and a joint travel to project vineyards in Asia in 2012, the well-known grape grower Valentin Blattner from Switzerland has affirmed his plans to cooperate with TVC in establishing a new research site and seedling facility in the tropics.

Mr.Blattner is one of the leading European grape variety hybridizers and known for innovative crossbreeds and ground-breaking results in the development of fungus resistant varieties. He plans to work on new PIWI varieties especially modified for tropical viticulture, for example by considering especially adapted vines from the Caribbean and Brazil (Vitis Caribea / Vitis Tiliifolia). The idea to locate these research efforts in a tropical country with existing viticultural infrastructure seems natural. One can build on sound experience and resources from the existing vineyard and facilities while benefiting from the uncomparable advantages of viticultural production in the tropics.

These include a year-round vegetation phase, which allows for a higher replication rate, continuous growth of seedlings (instead of being limited to summertime) and thus a much faster development of new varieties. In addition, the more far-reaching possibilities of regulating grape vine development in the tropics through pruning measures leads to the simultaenous florescence of both early and late blooming grape varieties. In selective breeding, this is a huge advantage, because it renders the complicated and costly storage of pollen unnecessary. Last but not least, speficic traits for grape varieties under tropical conditions can be tested in real time and in situ.

The knowledge and improved varieties thus gained will greatly benefit future tropical viticulture, and TVC is very much looking forward to this fruitful cooperation. (Source: TVC, Friedrichsdorf, March 2013)


Extensive Test Trials with Latest Fungus Resistant Grape Varieties (PIWIs)

TVC is implementing the as yet most comprehensive test trial of fungus resistant grape varieties in a tropical country. A new trial field with a selection of 25 most promising varieties has been established in late 2012 to gain more knowledge on the applicability and benefits of these special crossbreeds under tropical monsoon climate conditions. TVC has been succesfully growing fungus resistant grape varieties, also known as PIWIs, on trial sites in Asia since 1993. These efforts were funded and taken up by several pioneer winemaking companies. The latest test trial builds upon the experience of the last decades and also includes the latest generation of PIWIs, a field of viticultural development that is continuously advancing.

„PIWI“ is a German abbreviation and stands for "Pilzwiderstandsfähigen Reben", or fungus resistant grape varieties. These were created by crossing European grape varieties and American fungus resistant varietals. The resulting crossbreeds have been steadily improved since the 1950s, and today provide a high quality alternative to common wine varieties. They also scientifically belong to the type Vitis vinifera because they cannot be distinguished taxonomically.

The advantage of PIWIs lies in their resistance to fungal diseases, especially anthracose, downy and powdery mildew, which are the reason for most agrochemical treatments in viticulture. This problem is even more pronounced in the tropics, where humidity is often a problematic factor. The use of PIWIs under these circumstances can significantly reduce the application of fungicides, thus reducing environmental pollution and expenditures for spraying agents. (Source: PIWI International&TVC, Friedrichsdorf, February 2013)

Tropical Vineyards
Tropical Vineyards
Tropical Vineyard Management
Tropical Vineyard Management
Grape Leaves Production
Grape Leaves Production