The Vine is an area within the WBWE, conceived to encourage new businesses that evolve around wine and vine industries. Using every resource, and expanding every possibility, such an initiative shows the great potential that can be developed in the sector. High PressureProcessGroup, DeptIngeniería Química y TMA, Universidad de Valladolid, Valladolid, Spain. Instituto de TecnologiaQuímica e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal *Corresponding author. e-mail address: ana.alvarez@iq.uva.es Further information about "The Vine Science Award" on http://www.worldbulkwine.com/thevine/ing/posters.html

1. Ana Álvareza,*, Ana A. Matiasb,c, María José Coceroa, Rafael B. Matoa
a High Pressure Process Group, Dept Ingeniería Química y TMA, Universidad de Valladolid, Valladolid, Spain.
b Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
c iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
* Corresponding author. e-mail address: ana.alvarez@iq.uva.es
8thWORLDBULKWINEEXHIBITION,November21st-22ndAmsterdam,TheNetherlands
ACKNOWLEDGMENTS:
Authors acknowledge the project WineSense (FP7-MC-IAAP) and regional government project VA330U13 for funding. A.A. thanks the Spanish Ministry of Education for her
FPU grant (FPU13/04678). A.M. is grateful to FCT by her Investigator FCT grant fellowship.
MATERIALS AND METHODS
» Grape pomace from Tempranillos grape
• Matarromera winery (Spain)
• 2014 vintage
» Total polyphenol content (TPC)[1]
» Anthocyanin content (AC)[2]
» Chemical antioxidant activity [3]
» Cellular antioxidant activity [4]
CONCLUSIONS
Microwave step easy to implement at industrial scale
Simultaneous high polyphenol yield and richness
Anthocyanin richness is boosted by microwaves
MW pretreated extracts have higher antioxidant bioactivity4
3
2
1
BIBLIOGRAPHY
[1] Waterhouse, A. L. (2001). Determination of Total Phenolics. In
Current Protocols in Food Analytical Chemistry: John Wiley &
Sons, Inc.
[2] AOAC. (2005). AOAC Official Method 2005.02. Total
monomeric anthocyanin pigment content of fruit juices,
beverages, natural colorants, and wines. pH Differential
Method. In (Vol. 37.1.68): AOAC International.
[3] Lévai, G., Martín, Á., de Paz, E., Rodríguez-Rojo, S., & Cocero,
M. J. (2015). Production of stabilized quercetin aqueous
suspensions by supercritical fluid extraction of emulsions. The
Journal of Supercritical Fluids, 100, 34-45.
[4] Wang, H., & Joseph, J. A. (1999). Quantifying cellular oxidative
stress by dichlorofluorescein assay using microplate reader1.
Free Radical Biology and Medicine, 27(5–6), 612-616.
MICROWAVE PRETREATMENT
→Step prior to conventional
solid-liquid extraction
→Compact oven
→Homogeneous irradiation
→No thermal degradation
YIELD & RICHNESSObjective
GRAPE POMACE EXTRACT
Polyphenols (wt%)
INTRODUCTION
FINAL DRY PRODUCT
Extraction Drying
Polyphenols
(g)
YIELD: polyphenols
obtained from the
grape pomace
(mg/gDry Pomace)
RICHNESS: ratio between
polyphenols and total
extracted substances
(mg/gDry Extract)
Other substances
0.0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
0
2
4
6
8
10
12
14
16
0 30 60 90 120 150 180
ACyield(mgCGE/gDryPomace)
ACrichness(mgCGE/gDryExtract)
time (min)
Anthocyanins
MWpretreatment
0
500
1000
1500
2000
2500
3000
0
0.03
0.06
0.09
0.12
0.15
Conventional
extract
MW
anthocyanin
extract
MW
polyphenol
extract
ChemicalAA
(μmolTrolox/gDryResidue)
CellularAA
(μmolQuercetin/gDryResidue)
Cellular AA
Chemical AA
RESULTS AND DISCUSSION
0.0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
0
2
4
6
8
10
12
14
16
0 30 60 90 120 150 180
ACyield(mgCGE/gDryPomace)
ACrichness(mgCGE/gDryExtract)
time (min)
Yield and richness
contrary tendencies
Conventional extraction Microwave pretreatment + conventional solid-liquid extraction
0
5
10
15
20
25
30
35
40
0
50
100
150
200
250
300
0 30 60 90 120 150 180
TPCyield(mgGAE/gDryPomace)
TPCrichness(mgGAE/gDryExtract)
time (min)
Polyphenols
MWpretreatment
MW anthocyanin optimun
 EMW pretreat=0.14 kJ/mL
 t= 30 min
 40% greater yield
 85% richer extract
 83% higher cellular AA
Simultaneous maximum yield and richness
Antioxidant activity
MW polyphenol optimun
 EMW pretreat=0.33 kJ/mL
 t= 20 min
 57% greater yield
 35% richer extract
 133% higher cellular AA
MW effect on polyphenols is more prominent than on other undesired substances
►Polyphenols are extracted quicker than other undesired compounds
►Significant extraction time reduction to prevent polyphenol richness decay
EXPERIMENTAL PROCEDURE
HOMOGE-
NIZATION
MW
PRETREAT
COOL
DOWN
CONVENT.
EXTRAC.
Ethanol: water
(50 v%)
S:L=0.75 g/mL
S:L=0.50 g/mL
T=60ºC
Microwave pretreatment:
− 60-120 seconds of residence time
− Temperature increases to 80-100ºC
Grape pomace is a propitious source of polyphenols, whose
exploitation entails the valorisation of a valueless byproduct.
► Challenge: improve the extraction