Dissolved oxygen content in apple must: technological implications in cider processing

Abstract

Oxygen can influence the composition and quality of apple must and cider. In this study, the effect of unit operations on oxygen dissolution during apple must processing was investigated and the technological implications discussed. Oxygen dissolution after different apple must processing unit operations, and also the effect of enzymatic browning reaction on dissolved oxygen uptake were analysed. During pressing, the highest and first oxygen dissolution occurred in the must at 6.8 mg/L, on average. The enzymatic browning reaction after 10 min was responsible for an oxygen uptake above 80%. The addition of sulphur dioxide or maceration of crushed apple results in a must with more oxygen content, however the beverage colour is negatively affected. The incorporation of oxygen into the must by bubbling oxygen or the movement of liquid may not be effective owing to consumption by the reaction of residual polyphenol oxidase. Moreover, this can affect the alcoholic fermentation because of the oxidation of nutrients such as vitamins. If the apple must is depectinized, racked and filtered, there will be enough oxygen to obtain a quality cider. These results and observations can be useful for selecting unit operations in cider companies in order to improve the beverage quality.

Supplementation of amino acids in apple must for the standardization of volatile compounds in ciders

“…Thus, some producers used to add urea or ammonia to the apple must to prevent an incomplete alcoholic fermentation . However, the addition of oxygen by bubbling, or movement of the apple must, should be avoided, because this could oxidize important nutrients .…”

Aspectos tecnológicos do processamento de suco e fermentado alcoólico de caqui

“…Kakimel, a qual gerou um menor teor de oxigênio dissolvido no início da fermentação alcoólica. O oxigênio dissolvido no mosto é essencial para a formação de ergosterol na membrana plasmática da levedura durante o seu crescimento (ALBERTI et al, 2014). Na Figura 4(B), observam-se as curvas cinéticas calculadas a partir da perda de massa dos fermentadores devido à liberação do gás carbônico durante a fermentação alcoólica, que possibilitou a geração de dados de velocidade de fermentação.…”