Effect of Different Crown Cap Closures on Phenolics and Sensory Attributes of Bottle-Fermented Sparkling Wines

P. P. Minnaar1, P. Gerber3, M. Booyse2, N. Jolly1*

(1) Post-Harvest and Agro-Processing Technologies, ARC Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch, 7600, South Africa. (P.P. Minnaar retired).

(2) Agricultural Research Council, Biometry, Private Bag X5026, Stellenbosch 7600, South Africa.

(3) Colmant Cap Classique & Champagne, P O Box 602, Franschhoek, 7690, South Africa.

Bottle-fermented sparkling wines closed with crown caps of different O2 permeabilities while ageing on the yeast lees were investigated for their effect on phenolics and sensory attributes. The crown caps were denoted as reference (least permeable), Crown++ (intermediate permeability) and Crown+ (most permeable) to oxygen. Total phenolics and physiochemical parameters were measured using a spectrophotometric technique and infrared spectrometry, respectively. Individual phenolics were quantified using an HPLC technique. Dissolved oxygen was not significantly different between Crown+ and Crown++ wines. Crown+ wines were approx. 2% higher in flavan-3-ols than Crown++ wines and flavonols were approx. 8% higher in Crown+ wines than Crown++ wines.