Migration of Tannins and Pectic Polysaccharides from Natural Cork Stoppers to the Hydroalcoholic Solution

Abstract

Ellagitannins, condensed tannins, and pectic-derived polysaccharides were removed from natural cork stoppers using hydroalcoholic solution. Two main populations of migrated compounds were determined; the major one with molecular weight (M W ) between 0.2 and 1 kDa and the second with 2.1 kDa and polydispersity of 1.3. Two residual populations mainly composed of condensed tannins were also observed between 2.5 and 4.5 kDa and higher than 15 kDa. Simple, C-glycosidic, complex, and oligomeric ellagitannins were identified by high-performance liquid chromatography−diode array detection/electrospray ionizationmass spectrometry (HPLC−DAD/ESI-MS). Ellagitannins linked to condensed tannins and some pectic-derived polysaccharides were also tentatively identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS). This preliminary work opens an opportunity for the cork stoppers industry due to the relevance of this type of compounds on the astringency and bitterness of wines.

Sustainable Exopolysaccharide Production by Rhizobium viscosum CECT908 Using Corn Steep Liquor and Sugarcane Molasses as Sole Substrates

“…Methylation analysis was used to identify glycosidic linkages following a protocol described by Reis and co-workers [ 36 ]. Briefly, EPS were methylated using CH 3 I, dissolved in CHCl 3 :MeOH (1:1, v / v ), and dialyzed against 50% EtOH.…”

“…After solvent evaporation, the product obtained was hydrolyzed (trifluoroacetic acid 3 M), reduced (NaBD 4 (sodium borodeuteride)) and acetylated. The partially methylated alditol acetates (PMAAs) obtained were analyzed by gas chromatography–mass spectrometry (GC–qMS) according to Reis and co-workers [ 36 ]. For that purpose, a Shimadzu GCMS-QP2010 Ultra (Shimadzu Co., Tokyo, Japan), equipped with a HT5 (Trajan Scientific, Victoria, Australia) capillary column (30 cm length × 0.25 mm i.d., 0.1 μm film thickness), was used.…”

Structural differences on cell wall polysaccharides of brewer's spent Saccharomyces and microarray binding profiles with immune receptors

“…Neutral sugars were released from the polysaccharides by acid hydrolysis and analysed as their alditol acetates by gas-chromatography (Coimbra et al, 1996;Reis et al, 2020) using a Perkin Elmer-Clarus400 chromatograph with a split injector and a FID detector. A DB-225 column (30 m × 0.25 mm × 0.15 μm) was used.…”

Cork, a Natural Choice to Wine?

“…In another work, a wine model solution extracted ellagitannins, proanthocyanidins, and pectic-derived polysaccharides from natural cork stoppers, with simple C-glycosidic, complex, and oligomeric ellagitannins being identified by HPLC-DAD/ESI-MS. In addition, MALDI-TOF-MS was used for the identification of ellagitannins linked to proanthocyanidins and some pectic-derived polysaccharides [ 68 ].…”

“…In wine, tannins can undergo chemical transformations such as condensation with anthocyanins, pyranoanthocyanins, or other phenolic compounds, oxidation, or hydrolysis reactions in a slow but continuous way [ 83 ], yielding to the formation of more complex structures such as portisins [ 84 ], flavano-ellagitannins, and ethyl-vescalagin [ 85 ] or corklins (ellagitannin derivate compounds) [ 68 ]. While it is known that grape seed tannins contribute to the structure of wines, they can also cause excessive astringency.…”