Optimization of Fermentation Process of Low Alcohol Degree Cider with Cold Crushing Red Fuji Apple Pulp

Cold crashing apple pulp of red Fuji was used as raw materials to ferment and prepare the low degree cider. The fermentation strain was selected through the analysis of sugar content, alcohol content, pH and total acid in different yeast fermentation cycles. The single factor and response surface analysis were used to optimize the fermentation process to determine the best conditions for cold crashing apple pulp fermented cider, and the quality was compared with that of apple juice fermented cider by analyzing the cider indexes. The results showed that the optimal fermented parameters were initial sugar content 18%, SY yeast inoculation 0.1 g/L, and temperature 20℃. The residual sugar(7.5±0.46 g/L) and alcohol content(7.8±0.1%) of fermented apple pulp cider were compared with the residual sugar(7.3±0.31 g/L) and alcohol content(8.0%±0.1%) of fermented apple juice cider, and the difference was not significant. The contents of total phenols(74.99±1.23 mg/100 mL) and organic acids(5.33±0.01 g/L) in apple pulp fermented cider were higher than those in apple juice fermented cider(total phenols 47.5±2.2 mg/100 mL, organic acids 5.01±0.03 g/L). This research results could be used as reference for the cider production, and provide ideas for the apple processing industry to drive the diversified development.