FERMENTATION CHARACTERISTICS OF CAMPBELL EARLY GRAPE WINE INOCULATED WITH INDIGENOUS KOREAN WINE YEASTS ENCAPSULATED IN CA-ALGINATE BEADS AFTER AIR-BLAST DRYING

Abstract

The aim of this study was to test the possibility of using yeast cells encapsulated in calcium alginate (Ca-alginate) beads as a starter for wine fermentation. Characteristics of Korean Campbell Early wines fermented by five free yeast cell types and those encapsulated in 2% Ca-alginate beads were compared using physicochemical analyses and sensory evaluation tests. The encapsulated yeast cells were shown to ferment Korean Campbell Early grapes with a similar efficiency as that exhibited by the five free yeast cell-types. After fermentation, the characteristics of free cells and encapsulated cells did not show significant differences in terms of content of reducing sugars, soluble solids, total acids, organic acids, and free sugars, as well as in terms of viable cell numbers and other physicochemical properties. The encapsulated cells did, however, produce more alcohol than the free cells. Encapsulation in 2% Ca-alginate beads was furthermore found to decrease the production of negative volatile compounds. The sensory evaluation of wines fermented by free cells compared with those fermented by Ca-alginate bead-encapsulated cells yielded similar scores for the following properties: color, taste, flavor, and overall preference. Overall, no significant differences were observed between the two grape wines, and yeast cells encapsulated in 2% Ca-alginate beads therefore showed high stability and served as an effective yeast starter for wine fermentation.