FLAVOnoids in Fruits and Vegetables:their Impact on Food Quality,Nutrition and Human Health

Consumers’ websiteflavomail@vtt.fihttp://flavo.vtt.fi

Project websiteflavo04@versailles.inra.fr

http://www.flavo.info

© INRA 2007

Project FOOD-CT-2004-513960-FLAVO

Priority 5: Food Quality and Safety

"Let your food be your medicine, and your medicine be your food" Hippocrates, c. 460 BC - c. 370 BC

Consumers

Health / Life quality improvement

Food &Beverages

Fresh Fruit & Vegetables

Improved Crops

Project Update September 2007

Further reading• http://flavo.vtt.fi and http://www.flavo.info.

• Flavonoid oxidation in plants: from biochemical properties to physiological functions (2007).Pourcel et al. Trends in Plant Sciences, 12 : 29-36.

• Characterization of major enzymes and genes involved in flavonoid and proanthocyanidinbiosynthesis during fruit development in strawberry (Fragaria x ananassa) (2007). Almeida et al.Archives of Biochemistry and Biophysics, 465 : 61-71.

• Polyphenols compounds changes in the industrial production process of concentrated strawberryjuice (2007). Oszmianski et al. The Scientific organ of Polish Food Technologists’ Society, 14 : 94-104.

• Bioavailability, metabolism and bioactivity of food ellagic acid and related polyphenols.Tomás-Barberán et al. Book chapter in : Recent Advances in Polyphenol Research (Lattanzio, V. andDaayf, F., eds.) Blackwell Publishing, 2007.

Project partners1. Institut National de la Recherche Agronomique, France

(Project Coordinator) Versailles Loïc Lepiniec lepiniec@versailles.inra.fr(Project Manager) Versailles Enric Belles-Boix Enric.Belles-Boix@versailles.inra.fr

Montpellier Véronique Cheynier veronique.cheynier@supagro.inra.frRennes Sylvain Guyot sylvain.guyot@rennes.inra.fr

Clermont-Ferrand Augustin Scalbert scalbert@clermont.inra.fr2. Plant Research International B.V., Wageningen, The Netherlands Arnaud Bovy arnaud.boyy@wur.nl3. RIKILT, Instituut voor Voedselveiligheid, Wageningen, The Netherlands Peter Hollman peter.hollman@wur.nl4. Università degli studi di Firenze, Firenze, Italy Piero Dolara piero.dolara@unifi.it5. Wageningen Universiteit, Wageningen, The Netherlands Bart Gremmen bart.gremmen@wur.nl6. Ente per le Nuove Tecnologie, l'Energia e l'Ambiente, Rotondella, Italy Gaetano Perrott gaetano.perrotta@trisaia.enea.it7. Institute of Food Research, Norwich, United Kingdom Paul Kroon paul.kroon@bbsrc.ac.uk8. VTT - Technical Research Centre of Finland, Espoo, Finland Anna-Marja Aura anna-marja.aura@vtt.fi

Liisa Lahteenmaki liisa.lahteenmaki@vtt.fi9. Philipps Universität Marburg, Marburg, Germany Stefan Martens martenss@staff.uni-marburg.de10. Uniwersytet Przyrodniczy we Wroclawiu, Wroclaw, Poland Jan Oszmianski oszm@ozi.ar.wroc.pl11. Consejo Superior de Investigaciones Científicas, CEBAS, Murcia, Spain Francisco Tomas-Barberan fatomas@cebas.csic.es12. INTER RHONE, Avignon, France Laurent Barnavon lbarnavon@inter-rhone.com13. Universität Bielefeld, Bielefeld, Germany Bernd Weisshaar bernd.weisshaar@uni-bielefeld.de14. Nestec S.A., Lausanne, Switzerland Gary Williamson gary.williamson@rdls.nestle.com

EC Scientific Officer. Unit E3: Food, Health and Well-being, Directorate E Valérie ROLLAND Valerie.ROLLAND@ec.europa.eu

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What are the best raw products and processes to optimise flavonoidcomposition and quality in food?

• In apple, grape, and strawberry, the amounts and proportions of flavonoidspresent in fruits are largely influenced by varietal, developmental, geographical, andenvironmental factors. The final polyphenol composition in derived food products,such as cloudy juices, is greatly dependent on the production methods.• Freshly produced strawberry nectars contain higher amounts of flavonoids,especially of anthocyanins, than those stored for 6 months at 4oC and 30oC. Thesmallest antioxidant capacity is found in clear samples and the highest in pureesamples.• Industrial production of concentrated strawberry juice leads to a continuousloss of polyphenols , especially PAs, through the whole product ion process,particularly at pressing and, to a lesser extent, during the clarification andconcentration steps.• The effects of postharvest treatments, such as modified atmosphere packaging,ozone, and ultraviolet-C light, on the decay of strawberries are determined. Althoughnone of the treated samples show signs of fungal growth, all the bioactivecompounds are differently but significantly affected by most of the treatments. Noadditional effect is observed when several treatments are combined.• Tannin enriched wines were made using several technological processes, suchas flash release, tannin addition, run-off and enzyme addition. Flash release showthe best tannin enrichment with the doubling of total flavan-3-ol content.

PROJECT AIMSWith an increase of diseases related to lifestyle and ageing, the possibility of preserving human health byimproving plant food has become a major societal issue. Flavonoids, such as flavonols, anthocyanins andflavan-3-ols are plant polyphenolic compounds present in fruits and vegetables suggested to displayprotecting properties against cancer and cardiovascular diseases. Proanthocyanidins (PAs), also calledcondensed tannins, constitute a major fraction of the total flavonoids ingested in Western diets. Apples,grapes, and strawberries are rich sources of PAs and suitable candidates to develop plant-based food withmodified flavonoid content.

The objective of the FLAVO project is to provide the knowledge, tools and methods to enable developmentof high quality, consumer-acceptable fruits and vegetables and derived foods/beverages with optimal levelsof flavonoids for improving health. To date, FLAVO has achieved much progress in knowledge leading tomore than 50 presentations to the scientific community, peer-reviewed scientific articles and book chapters.

PROSPECTSAfter two years of work, FLAVO has produced the first signif icant results, demonstrating the fruitfulcollaboration between scientists of different fields within the consortium. For the 3rd year, novel results areexpected. Therefore, FLAVO has defined one major priority for 2008: to prepare a large campaign ofdissemination of all the results obtained within the project. Besides the participation to majorinternational conferences and the publication of a series of scientific papers (10 new peer-viewed scientificpapers have already been submitted for publication), several information–diffusion events will be organised.These include the production of information flyers and the organisation of an International Symposiumon Flavonoids and Functional Foods in Paris in 2008. In this meeting, representatives of the massmedia, research institutions, agriculture unions and the agro-industry will be invited.

PROJECT RESULTS

How do consumers perceive food products with modified flavonoidcontent? Are these products and the processes used to developthem acceptable by consumers? Are they economically profitable tothe agro-industries?

• The acceptance of new processes and crop improvements for modifying theflavonoid content in food is studied by focus group discussions in Finland, France,and the Netherlands.• Group discussions on consumers acceptance of tannin enriched winesconclude that:

• this product is expected to be « natural »• the credibility of a healthy wine is related back to the « terroir »• to ensure its credibility, a « healthy » red wine must have a real level of

quality. Scientific proofs should be provided with simple terms• too many technical details or product addition, as oak chips, should be

banned because considered as wine denaturation• Group discussions on acceptability of new fruit-based products withenhanced health qualities are under way, but naturalness, which is associated tohealthier products and processes, is one of the major rising concerns.• Costs induced by flavonoid enrichment procedures are minor expenses in wine-making, while alternative ageing processes to barrel storage provide considerablesavings.

What is the impact of PA and derived metabolites on human health?What are the optimal composition and doses of PA in plant foods /beverages for delivering health benefits?

• Experiments with animals fed with seeds containing different levels offlavonoids reveal that the antioxidants present in food help to limit the oxidativedamage to liver and colon DNA. Expression profiles indicate that flavonols exhibitantioxidant effects at systemic level, while anthocyanins have effects only on thecolon, probably due to their limited absorption.• Animal studies show that dealcoholised wine reduce the expression of genesencoding inflammatory cytokines, MMPs and proteasome degradation pathways.The protective role played by this wine is likely due to the polyphenols.• The effects of the intestinal bacteria on PAs are studied using an in vitro modeland grape and apple extracts. Fruit source and structural factors influence themicrobial metabolism of PAs in the intestine. The major products of colonicfermentation are identified. The condensed tannins, but not epicatechin, inhibit themicrobe-dependent production of metabolites.

What are the best tools for analysing and selecting fruits andvegetables with optimised flavonoid content?

• In grape 14,000 genes have already been identified. Amongst them, 2200 couldbe involved in PA synthesis. Further work is in progress to identify the mostimportant genes regulating the formation of PAs.• In the model plant Arabidopsis, the comparison of wild-type and mutant plantsreveals the genes involved in f lavonoid production. One of these mutants isimpaired in an enzyme involved in oxidative polymerisation of flavonoids and seedbrowning.• Ripe strawberries accumulate high amounts of anthocyanins and a large pool ofPAs. The structure of late flavonoid pathway genes, leading to the synthesis ofmajor compounds in ripe fruits, and the key steps in the biosynthesis of strawberryflavonoid end products are elucidated.• In strawberry, apple, grape, and Arabidopsis sequence polymorphisms in PAgenes are found. In apple and grape varieties these polymorphims correlate withPA content, composition and mean degree of polymerization. Novel marker traits forflavonoid content are found in grape and in Arabidopsis.• Strawberries over-expressing different combinations of Arabidopsis transcriptionfactor genes display elevated levels of PAs.