Hydroxycinnamate decarboxylase in Metschnikowia pulcherrima promotes the formation of vinylphenolic pyranoanthocyanins to enhance the color stability of blueberry wine

Blueberry wine is popular among consumers due to its high nutritional value, appealing color, and potential health benefits. However, the instability of its color during the brewing process poses challenges for storage and the overall growth of the blueberry wine industry. This study found that vinylphenolic pyranoanthocyanins in blueberry wine provide a more stable color than their anthocyanin precursors. The presence of yeast with hydroxycinnamic acid decarboxylase (HCDC) enhances the formation of vinylphenolic pyranoanthocyanins. Metschnikowia pulcherrima Y4, isolated from decayed blueberry peels, promotes the production of six specific vinylphenolic pyranoanthocyanins in blueberry wine: malvidin-4-vinylcatechol, delphinidin-3-arabinoside-4-vinylcatechol, cyanidin-3-galactoside/glucoside (C3G)-4-vinylcatechol, cyanidin-3-O-arabinoside-4-vinylcatechol, malvidin-3-O-glucoside/galactoside-4-vinylcatechol, and C3G-4-vinylphenol. Blueberry wine fermented solely with M. pulcherrima Y4 exhibits a 25% increase in light stability under direct outdoor light conditions and a 19% increase in temperature stability at 60 °C compared to Saccharomyces cerevisiae K1. Furthermore, the use of M. pulcherrima Y4 in fermenting blueberry wine significantly decreases the time required to form vinylphenolic pyranoanthocyanins to eight days. Hence, M. pulcherrima Y4 is highly effective in accelerating the synthesis of these compounds, providing a valuable approach for improving the stability and color of blueberry wine.