A. Flavour Quality and Ageing RESEARCH ACTIVITY-INBR. B. Yeast and Bioflavours C. Raw Materials and Mycotoxins

Transcription

1 A.1. New methodologies in flavour research A.2. Aroma profile & organoleptic stability A.3. Antioxidants & polyphenols A. Flavour Quality and Ageing RESEARC ACTIVITYINBR B. Yeast and Bioflavours C. Raw Materials and Mycotoxins

2 A.3. Antioxydants & polyphenols Flavanoïds : antioxidant activity, stability through storage, impact of the technological process reduction power measurements (AAP, ESR,..), structure determination by PC/MS and thiolysis, selection of lowfermented cocoa varieties and lowbitter hop cultivars, stability in beer and chocolate Resveratrol and stilbene analogs!!! «French paradox» Discovery in hop and cocoa hop and cocoaderived drinks, selection of hop and cocoa varieties, production of enrichedextracts Melanoïdins structure, antioxydant activity and colour, chocolate, special malts

3 Polyphenols Phenolic acids Flavonoids Stilbens Benzoic acid C ()n ()n Cinnamic acid ()n C Antioxidant, aroma precursors ()n Flavonols Flavanoids Prenylchalcones Flavanones 3,4Flavanediols Flavan3ols Flavones Isoflavones Anthocyanidins ()n ()n ealth benefits (cardioprotector, anticarcinogenic, antiinflammatory, ) Antioxidant, astringency, color, health benefits (cardioprotector, estrogenic activities, )

4 Flavonoïds : J. Agric. Food Chem., 51 (23), J. Agric. Food Chem., 48 (2),

5 P4 P5 P6 P7 Trolox BT Acide férulique P1 (+)Catéchine P2 Quercétine.22 Acide caféique P3 Vitamine E Vitamine C Resvératrol Glutathion P1 (+)cat catéchine chine ~ 1 min / ppm P7 ~ 772 min / ppm

6 1 5 Cocoa procyanidin extract used as standard ESI()MS/MS with N4 + P1 P1 Sephadex 2 aqueous acetone 7% extract of a extract of a lager beer Relative Abundance P2 P3 P4 P2 P3 1 5 P5 1 P Time (min) Time (min) Callemien and Collin, submitted 27

7 Small oligomers Thiolysis of pure beer fractions isolated by NPPCUV from a Sephadex 2 beer extract (+)Catechin ()Epicatechin ()Gallocatechin ()Epigallocatechin 3,4α and β Catechin benzylthioether 3,4βEpicatechin benzylthioether 3,4α and β Gallocatechin benzylthioether More catechin in the monomers P1 (%) P2 (%) P3 (%) More Catechin in the terminal units of the dimers extension More Catechin in the terminal units of the trimers Gallocatechin in the extension Procyanidin B3 Prodelphinidin C2

8 Flavanoids Malt op Fresh beer Flavan3ols (+)Catechin R 1 =, R 2 =, R 3 =, D 8 7 A 6 5 3' 4' 1 B 2 5' R3 C R1 3 4 R2 ()Epicatechin ()Gallocatechin ()Epigallocatechin R 1 =, R 2 = R 3 = R 1 =, R2 = R 3 = R 1 =, R 2 =, R 3 =, D, D, D Procyanidins B B1 ()Epicatechin(4β 8)(+)catechin, N! B2 ()Epicatechin(4β 8)()epicatechin B3 (+)Catechin(4α 8)(+)catechin, D B4 (+)Catechin(4α 8)()epicatechin, N! Prodelphinidins B B3 ()Gallocatechin(4α8)(+)catechin, D B9 ()Epigallocatechin(4β8)(+)catechin (+)Catechin(4α8)()gallocatechin (+)Catechin(4α6)()gallocatechin ()Gallocatechin(4α6)(+)catechin Prodelphinidins A ent ()Epigallocatechin(4α8, 2α7)(+)catechin ent ()Epigallocatechin(4α6, 2α7)(+)catechin Propelargonidin B (+)Afzelechin(4α 8)(+)catechin Procyanidins C C2 (+)Catechin(4α8)(+)catechin(4α 8)(+)catechin, N! ()Epicatechin(4β 8)(+)catechin(4α 8)(+)catechin ()Epicatechin(4β 8)()epicatechin(4β 8)(+)catechin Prodelphinidins C ()Gallocatechin(4α 8)()gallocatechin(4α 8)(+)catechin, N! ()Gallocatechin(4α 8)(+)catechin(4α 8)(+)catechin, N! (+)Catechin(4α 8)()gallocatechin(4α 8)(+)catechin

9 Beer yellowbrown colour increases through storage ager beer PVPP glass bottle ager beer PVPP PET bottle 1 1 EBC colour EBC colour Time (months) Time (months) ager beer Silica glass bottle EBC colour C D 2 C D Time (months) EBC = Absorption at 43 nm (45 nm yellowbrown) Callemien and Collin, JAFC, 27

10

11 (+) catechin at 4 C, 2 C with and without light Yellowbrown colour : impact of temperature and light! EBC colour Impact of light! of light Impact of temperature! 4 C D 2 C 2 C D (+)Catechin concentration (mg/) Impact of temperature Impact of light 2 C, 2 C, D 4 C, D Time (days) Time (days) 2 C, 2 C, D 4 C, D EBC = Absorption at 43 nm (45 nm yellowbrown)

12 5 days at 2 at 2 C darkness Degradation of (+) catechin Formation of polar and apolar dimers and trimers 31 days at 2 at 2 C darkness RT: SM: 13G Relative Abundance m/z Monomers (+)catechin. 55. SM: 13G (+)catechin Relative Abundance m/z Dimers polar apolar apolar Relative Abundance m/z Trimers Time (min) Time (min)

13 8 (+)catechin + 2 oquinone catechin Michael addition 2 8 inverse dismutation Mw 578 n 4 Dehydrodicatechin B4 colourless Radicalar addition 2 catechin semiquinon Mw 578 n 7 Dehydrodicatechin B colourless (Guyot et al., 1996, Phytochemistry)

14 xidation Radicalar addition Radicalar addition Mw 576 n 13 Dehydrodicatechin A yellowbrown Mw 576 n 11 Dehydrodicatechin Ayellow/brown

15 Stilbenes J. Agric. Food Chem., 53 (25),

16

17 W illam et t e (USA) 24 W illam et t e (USA) 26 Cascade (USA) 24 W arrior (USA) 24 Jerkovic & Collin, Journal of Agricultural and Food Chemistry, 55 (21), 27, Nugget (USA) 24 Cascade (USA) 26 Saaz (CZ) 26 T omahawk (USA) 24 Simcoe (USA) 24 Sladeck (CZ) 26 Nugget (USA) 25 T omahawk (USA) 26 Cascade (USA) 25 W illam et t e (USA) 25 W arrior (USA) 26 W arrior (USA) 25 Saaz (CZ) 25 Spalter (G) 26 Saphir (G) 26 Nugget (G) 26 Simcoe (USA) 25 allertau T aurus (G) 26 T omahawk (USA) 25 ersbrucker Spat (G) 26 allertau T radition (G) 26 Sm aragd (G) 26 allertau Magnum (G) 26 allertau Mittlefrüher (G) 26 P remiant (CZ) 25 W ye T arget (G) 26 Nugget (G) 25 W ye T arget (G) 25 Saphir (G) 25 allertau T radition (G) 25 allertau T aurus (G) 25 Sm aragd (G) 25 allertau Magnum (G) 25 Spalter (G) 25 ersbrucker Spat (G) 25 allertau Mittelfruher (G) transpiceid transresveratrol Necessary but not sufficient American varieties ow αacids < 5.5 %! arvestdependant A GERMAN VARIETIES Stilbene concentration (mg/kg)

18