EVOLUTION OF PHENOLIC COMPOUNDS DURING WINEMAKING AND MATURATION UNDER MODIFIED ATMOSPHERE

Transcription

1 EVOLUTION OF PHENOLIC COMPOUNDS DURING WINEMAKING AND MATURATION UNDER MODIFIED ATMOSPHERE A. Bimpilas, D. Tsimogiannis, V. Oreopoulou Laboratory of Food Chemistry and Technology, School of Chemical Engineering, National Technical University of Athens (NTUA)

2 Phenolic substances of wine Anthocyanidins Phenolic acids Flavan-3-ols Flavonols Malvidin Gallic Catechin Quercetin Delphinidin Caffeic Epicatechin Kaempferol Cyanidin P-coumaric Procyanidins Myricetin Petounidin Peonidin

3 Anthocyanins 3-Ο-glucoside 3-Ο-(6 -acylated)- glucoside

4 Reactions between phenolic compounds during storage Anthocyanins Flavanols Polymeric pigments Anthocyanin Flavanol Flavanol-Anthocyanin adduct Anthocyanin-Flavanol adduct Methylmethine Flavanol- Anthocyanin adduct

5 Use of inert gases during storage Wine is protected from oxidative spoilage The initial good quality (fruit bouquet, color and flavor) is ensured Phenolic compounds of wine are protected

6 EXPERIMENTAL

7 Vinifications Allagiannis winery [Markopoulo, Attica ] Avantis Estate [Chalkida, Evia] Pilot plant of the department of oenology and beverage technology [Technological Educational Institute of Athens] Cultivars 1) Merlot 2) Syrah Alcoholic fermentation 3) Mavrokountoura Stabilization Packaging laminated bags [20mL] Origin of cultivation Markopoulo, Attika Kymi, Evia 4) Agiorgitiko Nemea, Korinthos Maceration process pectinolytic enzymes Cold maceration under modified atmosphere (70% N2, 30% CO2) pectinolytic enzymes N2 CO2 N2-CO2 (1:1)

8 Methods Total Phenols (Folin-Ciocalteu assay) Antiradical activity (DPPH assay) Samples Chromatography (SPE HPLC-DAD, LC-MS/MS) Color Measurement (Spectrophotometer)

9 RESULTS AND DISCUSSION

10 Identification of individual phenolic compounds with HPLC mau 500 Mv-3-glc Dp-3-glc Pt-3-glc Pn-3-glc Mv-3-acglc Mv-3-coumglc Pn-3-acglc Pn-3-coumglc Pt-3-acglc Pt-3-coumglc min mau M-3-glc Q-3-glcr Q-3-glc Q M-3-glcr L-3-glc M I-3-glc S-3-glc min

11 Extraction of phenolic compounds during vinification TP, FA, TF [ppm] Syrah Free Syrah anthocyanins [ppm Mv-3- glc] Total Flavonols Total Phenols Free Anthocyanins Total Flavonols Merlot 2143± ± ± ±0.002 TF [ppm] Total Phenols [ppm gallic acid] Days Days CI HUE Syrah 1954± ± ± ±0.003 Mavrokountoura 2165± ± ± ±0.002 Agiorgitiko 2550± ± ± ±0.001

12 Total phenolic content and antiradical activity MERLOT SYRAH % change of antiradical activity between 360 and 600days TP [ppm GAE] N2-23% -45% CO2-60% -50% N2-CO2 (1:1) -38% -42% Time of Storage [d] N2 CO2 MIX

13 The decline of free anthocyanins during storage Mv-3-glc Mv-3-acglc Mv-3-coumglc Packaging Variety atmosphere k [mon -1 ] R 2 k [mon -1 ] R 2 k [mon -1 ] R 2 90 Mv-3-glc Mv-3-acglc Mv-3-coumglc N Merlot 4 CO N 2 -CO 2 (1:1) y = -0,2988x + 4, Mv-3-glc R² = 0,9859 N Mv-3-acetglc Syrah CO Mv-3-coumglc y = -0,2858x + 3,7479 N R² = 0, CO 2 (1:1) N y = -0,271x + 3,285 Mavrokountoura CO R² = 0, N 2 -CO 2 (1:1) ,0 0 1,0 50 2,0 3, , ,0 6, , ,0 N Months Time of storage [d] Agiorgitiko CO Mavrokountoura [N2-CO2] N 2 -CO 2 (1:1) ln[anthocyanin] ppm Mv-3-glc Determination Decline of Malvidin-3-O-glucosides of k for 1 st order reaction

14 Color parameters CI CI 1,800 1,800 1,600 1,600 1,400 1,400 1,200 1,200 1,000 1,000 Merlot Syrah 0,800 0,800 0,600 0,600 0,400 0, Time Time of of storage storage [d] [d] N2 N2 CO2 CO2 MIX MIX 1,200 1,400 1,300 1,100 Merlot Syrah HUE HUE 1,200 1,000 1,100 0,900 1,000 0,800 0,900 0,700 0,800 0,600 0, Time of storage [d] Time of storage [d] N2 N2 CO2 CO2 MIX MIX

15 Hydrolysis of wine flavonols during storage % increase of total flavonol aglycones during storage Merlot Syrah Mavrokountoura N2 20% CO2 11% N2-CO2 (1:1) 18% N2 35% CO2 10% N2-CO2 (1:1) 18% N2 4% CO2 3% N2-CO2 (1:1) 4%

16 Conclusions The extraction of individual phenolic compounds during maceration differs with time and maceration procedure and optimal conditions can be designed for each variety Packaging atmosphere can affect the total phenolic content, antiradical activity, and the rate of polymerization reactions between phenolic compounds during wine storage The use of pectinolytic enzymes during vinification may lead to hydrolysis of certain glycosylated phenolic compounds, whereas increased carbon dioxide concentration during storage may inhibit such enzymatic reactions Our results showed that industry can select the optimum inert gas consistency for each grape variety, to favor quick reduction of free anthocyanins and wine stability

17 Thank you