Influence of acerola pulp concentration on mead production by Saccharomyces cerevisiae AWRI 796

In this work the influence of acerola (Malpighiae marginata DC) pulp, at concentrations of 0, 10, 15, 25 and 30%, on mead production by Saccharomyces cerevisiae AWRI 796 was evaluated. A novel approach based on cell growth to obtain high accuracy fits for the data and to estimate optimization parameters such as Gibbs free energy was used. Fermentation was done using 107 cells/mL at pH 5.0 and 30 °C for up to 288 h. The addition of increasing concentrations of acerola pulp progressively enhanced the cell growth, with the highest cell concentration reached being ∼2.09 × 108 cells/mL. Under these conditions, the lowest Gibbs free energy of growth was −4.81 kJ/mol after fermentation for 288 h at a pulp concentration of ∼18%. The velocity of substrate consumption was −14 × 10−3 A.U./h whereas the velocity of ethanol formation was 17 × 10−3 A.U./h with ethanol production of 15.2% v/v or 120.1 g/L.