Evaluation of chemical and fermentation parameters during the preparation of wine from berry (<i>Maesobotyra standii</i>)

Abstract

Amilky red wine was produced from locally sourced berry (Maesobotyra standii) in Abraka, Delta State, Nigeria using innate wild yeast (Saccharomyces cerevisiae) augmented with baker’s yeast activated with 2, 5 and 10% (w/v) sugar solutions in activated yeast: fruit extract ratios of 1:2 and 1:3. It was observed that there was an inverse proportional relationship between percentage (%) titratable acidity and pH as well as for specific gravity (SG) and percentage (%) alcohol for 48 h after which both SG and % alcohol increased. Diauxic growth and malo-lactic fermentation were observed. Total aerobic counts followed same trend as for % alcohol. pH, % titratable acidity, specific gravity, % alcohol and total aerobic counts at 72 h fermentation ranged from 4.85 - 5.85, 0.955 - 1.152, 0.956 - 1.141, 0.54 - 2.62 and 0.95 - 185 x 10³ cfu/ml, respectively. The baker’s yeast activated with 5% (w/v) granulated sugar was most suitable for home or commercial berry wine production which gave wine with lower alcoholcontent (1.84%, v/v alcohol) using 1:2 activated baker’s yeast : fruit extract ratio; it gave wine with slightly higher alcohol-content (2.62%, v/v alcohol) with 1:3 baker’s yeast : fruit extract ratio. Thus portable and/or commercial wine can be produced from berry (M. standii) with baker’s yeast activated with 5% (w/v) granulated sugar.

Key words: Berry wine, sugar, baker’s yeast, malo-lactic, fermentation.