A ready-to-use freeze-dried juice and immobilized yeast mixture for low temperature sour cherry (Prunus cerasus) wine making

Abstract

The aim of this study was to develop a bioprocess for low temperature fruit wine making from ready-to-use freeze-dried raw materials: sour cherry (Prunus cerasus) juice and the psychrotolerant and alcohol resistant yeast strain Saccharomyces cerevisiae AXAZ-1 immobilized on porous delignified cellulose. The effect of storage time of the freeze-dried raw materials at 4°C (0, 30, and 60 days) on the fermentation efficiency of the yeast, as well as on the quality of the produced wines was evaluated. Sweet wines (>14% v/v alcohol) were produced without need for extra commercial alcohol addition. The sweet, sour cherry wines produced at 10°C using the freeze-dried raw materials, were analyzed for their aroma profile by headspace SPME GC–MS analysis as well as for their sensory attributes. All wines had similar aroma characteristics with fresh and fruity (cherry) notes, and high esters content. The fermentation kinetics and the sensory characteristics indicate the potential of the freeze-dried raw materials as a ready-to-use mixture for good quality sour cherry sweet wine making even at low temperatures.